1
|
Eguchi G, Takagi T, Torisawa S, Takehara K. Drafting behaviors in fish induced by a local pressure drop around a hydrofoil model. J Theor Biol 2024; 588:111821. [PMID: 38649020 DOI: 10.1016/j.jtbi.2024.111821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 03/29/2024] [Accepted: 04/03/2024] [Indexed: 04/25/2024]
Abstract
Fish schooling has the improvement in hydrodynamic propulsive efficiency through the interaction of flow field induced by fish bodies and tail beat. Such energy-saving behaviors due to flow interactions also occur with changes in the flow field caused by structures. We examined the differences between a live fish swimming around a streamlined hydrofoil model prepared to represent fish body and swimming alone in a flow tank. We observed that the fish can remain in the same place without tail beating. It called "drafting" behavior. The analysis of fish drafting showed that fish obtained thrust using a local pressure drop caused by the high velocity flow even in the vicinity of the hydrofoil model at an angle of attack α of 10° to 20°without flow separation, and fish balanced forces by using an α of fish body. This tendency was confirmed in the model experiment using a two-axis load cell, and the forces acting on the fish body was the smallest value when the fish model was placed in the same conditions as a live fish experiment. We also confirmed by simulation and found that the α of fish body generated lift force and counteract the suction force. Above results indicate that a fish can balance the anterior-posterior and lateral direction forces by using a local pressure drop around a hydrofoil model as suction force, and using angle of attack on its body, thereby realizing drafting.
Collapse
Affiliation(s)
- Go Eguchi
- Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1, Minato-cho, Hakodate, Hokkaido 041-8611, Japan.
| | - Tsutomu Takagi
- Faculty of Fisheries Sciences, Hokkaido University, 3-1-1, Minato-cho, Hakodate, Hokkaido 041-8611, Japan
| | - Shinsuke Torisawa
- Faculty of Agriculture, Kindai University, 3327-204 Nakamachi, Nara City, Nara 631-8505, Japan
| | - Kohsei Takehara
- Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashiosaka City, Osaka 577-8502, Japan
| |
Collapse
|
2
|
Liu S, Yuan X, Shao Z, Xiang K, Huang W, Tian H, Hong F, Huang Y. Investigation of singlet oxygen and superoxide radical produced from vortex-based hydrodynamic cavitation: Mechanism and its relation to cavitation intensity. Sci Total Environ 2024; 929:172761. [PMID: 38670357 DOI: 10.1016/j.scitotenv.2024.172761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 04/23/2024] [Accepted: 04/23/2024] [Indexed: 04/28/2024]
Abstract
Presently, the hydroxyl radical oxidation mechanism is widely acknowledged for the degradation of organic pollutants based on hydrodynamic cavitation technology. The presence and production mechanism of other potential reactive oxygen species (ROS) in the cavitation systems are still unclear. In this paper, singlet oxygen (1O2) and superoxide radical (·O2-) were selected as the target ROS, and their generation rules and mechanism in vortex-based hydrodynamic cavitation (VBHC) were analyzed. Computational fluid dynamics (CFD) were used to simulate and analyze the intensity characteristics of VBHC, and the relationship between the generation of ROS and cavitation intensity was thoroughly revealed. The results show that the operating conditions of the device have a significant and complicated influence on the generation of 1O2 and ·O2-. When the inlet pressure reaches to 4.5 bar, it is more favorable for the generation of 1O2 and ·O2- comparing with those lower pressure. However, higher temperature (45 °C) and aeration rate (15 (L/min)/L) do not always have positive effect on the 1O2 and ·O2- productions, and their optimal parameters need to be analyzed in combination with the inlet pressure. Through quenching experiments, it is found that 1O2 is completely transformed from ·O2-, and ·O2- comes from the transformation of hydroxyl radicals and dissolved oxygen. Higher cavitation intensity is captured and shown more disperse in the vortex cavitation region, which is consistent with the larger production and stronger diffusion of 1O2 and ·O2-. This paper shed light to the generation mechanism of 1O2 and ·O2- in VBHC reactors and the relationship with cavitation intensity. The conclusion provides new ideas for the research of effective ROS in hydrodynamic cavitation process.
Collapse
Affiliation(s)
- Shuchang Liu
- College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang 443002, China; Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang 443002, China
| | - Xi Yuan
- College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang 443002, China; Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang 443002, China
| | - Zhewen Shao
- College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang 443002, China; Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang 443002, China
| | - Kexin Xiang
- College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang 443002, China; Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang 443002, China
| | - Wenfang Huang
- College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang 443002, China
| | - Hailin Tian
- Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang 443002, China
| | - Feng Hong
- College of Mechanical and Power Engineering, China Three Gorges University, Yichang 443002, China; Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang 443002, China.
| | - Yingping Huang
- College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang 443002, China; Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang 443002, China.
| |
Collapse
|
3
|
Wong ZY, Azimi M, Khamooshi M, Wickramarachchi A, Burrell A, Gregory SD. The impact of small movements with dual lumen cannulae during venovenous extracorporeal membrane oxygenation: A computational fluid dynamics analysis. Comput Methods Programs Biomed 2024; 250:108186. [PMID: 38692252 DOI: 10.1016/j.cmpb.2024.108186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 04/15/2024] [Accepted: 04/17/2024] [Indexed: 05/03/2024]
Abstract
BACKGROUND AND OBJECTIVES Venovenous Extracorporeal Membrane Oxygenation (VV ECMO) provides respiratory support to patients with severe lung disease failing conventional medical therapy. An essential component of the ECMO circuit are the cannulas, which drain and return blood into the body. Despite being anchored to the patient to prevent accidental removal, minor cannula movements are common during ECMO. The clinical and haemodynamic consequences of these small movements are currently unclear. This study investigated the risk of thrombosis and recirculation caused by small movements of a dual lumen cannula (DLC) in an adult using computational fluid dynamics. METHODS The 3D model of an AVALON Elite DLC (27 Fr) and a patient-specific vena cava and right atrium were generated for an adult patient on ECMO. The baseline cannula position was generated where the return jet enters the tricuspid valve. Alternative cannula positions were obtained by shifting the cannula 5 and 15 mm towards inferior (IVC) and superior (SVC) vena cava, respectively. ECMO settings of 4 L/min blood flow and pulsatile flow at SVC and IVC were applied. Recirculation was defined as a scalar value indicating the infused oxygenated blood inside the drainage lumen, while thrombosis risk was evaluated by shear stress, stagnation volume, washout, and turbulent kinetic energy. RESULTS Recirculation for all models was less than 3.1 %. DLC movements between -5 to 15 mm increased shear stress and turbulence kinetic energy up to 24.7 % and 11.8 %, respectively, compared to the baseline cannula position leading to a higher predicted thrombosis risk. All models obtained a complete washout after nine seconds except for when the cannula migrated 15 mm into the SVC, indicating persisting stasis and circulating zones. CONCLUSION In conclusion, small DLC movements were not associated with an increased risk of recirculation. However, they may increase the risk of thrombosis due to increased shear rate, turbulence, and slower washout of blood. Developing effective cannula securement devices may reduce this risk.
Collapse
Affiliation(s)
- Zhun Yung Wong
- Cardio-Respiratory Engineering and Technology Laboratory (CREATElab), Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, VIC, Australia
| | - Marjan Azimi
- Cardio-Respiratory Engineering and Technology Laboratory (CREATElab), Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, VIC, Australia.
| | - Mehrdad Khamooshi
- School of Mechanical, Medical and Process Engineering and the Centre for Biomedical Technologies, Queensland University of Technology, Brisbane, Australia
| | - Avishka Wickramarachchi
- Cardio-Respiratory Engineering and Technology Laboratory (CREATElab), Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, VIC, Australia
| | - Aidan Burrell
- Department of Intensive Care and Hyperbaric Medicine, Alfred Hospital, Melbourne, Australia; ANZ Intensive Care Research Centre (ANZIC-RC), Dept. of Epidemiology and Preventive Medicine, Monash University, Australia
| | - Shaun D Gregory
- Cardio-Respiratory Engineering and Technology Laboratory (CREATElab), Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, VIC, Australia; School of Mechanical, Medical and Process Engineering and the Centre for Biomedical Technologies, Queensland University of Technology, Brisbane, Australia
| |
Collapse
|
4
|
Abrofarakh M, Moghadam H, Abdulrahim HK. Investigation of direct contact membrane distillation (DCMD) performance using CFD and machine learning approaches. Chemosphere 2024; 357:141969. [PMID: 38604515 DOI: 10.1016/j.chemosphere.2024.141969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 03/24/2024] [Accepted: 04/08/2024] [Indexed: 04/13/2024]
Abstract
Direct Contact Membrane Distillation (DCMD) is emerging as an effective method for water desalination, known for its efficiency and adaptability. This study delves into the performance of DCMD by integrating two powerful analytical tools: Computational Fluid Dynamics (CFD) and Artificial Neural Networks (ANN). The research thoroughly examines the impact of various factors, such as inlet temperatures, velocities, channel heights, salt concentration, and membrane characteristics, on the process's efficiency, specifically calculating the water vapor flux. A rigorous validation of the CFD model aligns well with established studies, ensuring reliability. Subsequently, over 1000 data points reflecting variations in input factors are utilized to train and validate the ANN. The training phase demonstrated high accuracy, with near-zero mean squared errors and R2 values close to one, indicating a strong predictive capability. Further analysis post-ANN training shed light on key relationships: higher membrane porosity boosts water vapor flux, whereas thicker membranes reduce it. Additionally, it was detailed how salt concentration, channel dimensions, inlet temperatures, and velocities significantly influence the distillation process. Finally, a mathematical model was proposed for water vapor flux as a function of key input factors. The results highlighted that salt mole fraction and hot water inlet temperature have the most effect on the water vapor flux. This comprehensive investigation contributes to the understanding of DCMD and emphasizes the potential of combining CFD and ANN for optimizing and innovating water desalination technology.
Collapse
Affiliation(s)
- Moslem Abrofarakh
- Department of Chemical Engineering, Faculty of Engineering, University of Sistan and Baluchestan, Zahedan, Iran
| | - Hamid Moghadam
- Department of Chemical Engineering, Faculty of Engineering, University of Sistan and Baluchestan, Zahedan, Iran.
| | - Hassan K Abdulrahim
- Water Research Center (WRC), Kuwait Institute for Scientific Research (KISR), P.O. Box 24885, 13109, Safat, Kuwait
| |
Collapse
|
5
|
Yu C, Shao M, Zhang W, Huang M, Wang G. Enhancing heat transfer efficiency in corrugated tube heat exchangers: A comprehensive approach through structural optimization and field synergy analysis. Heliyon 2024; 10:e30113. [PMID: 38707290 PMCID: PMC11068614 DOI: 10.1016/j.heliyon.2024.e30113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 04/11/2024] [Accepted: 04/19/2024] [Indexed: 05/07/2024] Open
Abstract
In this paper, a precise and efficient method to optimize corrugated tube heat exchangers is proposed by combining computational fluid dynamics simulation with optimization. The optimization of tubular heat exchangers involves contradictory Colburn coefficient j, and the friction coefficient f, so it is a multi-objective optimization problem. The approximate model is obtained by an extreme learning machine, and the structure parameter of the heat exchanger is optimized by the nondominated sorting genetic algorithm-Ⅱ. Compared to the results between the original and optimized tube, the optimized structure Colburn coefficient increased by 5.1 % and the friction coefficient decreased by 9.3 %. Finally, the internal flow field is compared qualitatively from temperature, pressure, and velocity. The optimization effect is further emphasized by using the field synergy theory.
Collapse
Affiliation(s)
- Chao Yu
- Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, China
| | - Mingzhen Shao
- Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, China
| | - Wenbao Zhang
- Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, China
| | - Mian Huang
- Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, China
| | - Gaugnyi Wang
- Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, China
| |
Collapse
|
6
|
Alali Z, Eckels S. 3D numerical simulations of mixed convective heat transfer and correlation development for a thermal manikin head. Heliyon 2024; 10:e30161. [PMID: 38707386 PMCID: PMC11066631 DOI: 10.1016/j.heliyon.2024.e30161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 04/17/2024] [Accepted: 04/21/2024] [Indexed: 05/07/2024] Open
Abstract
The head represents 10 % of the body's total surface area. Unprotected, it accounts for a significant portion of overall heat loss when exposed to cold conditions. This study was motivated by a need to clarify how the human head interacts with its environment in terms of heat exchange. Accurate estimations of heat transfer coefficients on the human head are essential for conducting thermal comfort and safety analyses in buildings. In this study, a thermal head resembling a real male human head is utilized to investigate heat transfer between the body and the surrounding environment. A three-dimensional computational fluid dynamics (CFD) model is proposed to simulate steady-state dry heat loss from the human head within a chamber. This model provides predictions for heat flux, temperature, and velocity distribution surrounding the head. A straightforward correlation, derived from numerical and experimental findings, is introduced to forecast the average Nusselt number for the head under combined natural and forced convection. This correlation, relying on dimensionless parameters (Grashof, Reynolds, and Prandtl numbers), offers enhanced accuracy, simplicity, and fewer terms. The predicted average Nusselt numbers from the proposed correlation for mixed convection closely match CFD and experimental results, with relative percentage differences within ±2 %, signifying excellent accuracy across a broader range of flow conditions, including temperature differences and air velocities. Additionally, the study explores the impact of head diameter on overall heat transfer.
Collapse
Affiliation(s)
- Zubieda Alali
- Department of Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS, 66506, USA
| | - S.J. Eckels
- Department of Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS, 66506, USA
| |
Collapse
|
7
|
Mehta T, Aziz H, Sen K, Chang SY, Nagarajan V, Ma AWK, Chaudhuri B. Numerical study of drop dynamics for inkjet based 3D printing of pharmaceutical tablets. Int J Pharm 2024; 656:124037. [PMID: 38522489 DOI: 10.1016/j.ijpharm.2024.124037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/19/2024] [Accepted: 03/21/2024] [Indexed: 03/26/2024]
Abstract
Interest in 3D printing has been growing rapidly especially in pharmaceutical industry due to its multiple advantages such as manufacturing versatility, personalization of medicine, scalability, and cost effectiveness. Inkjet based 3D printing gained special attention after FDA's approval of Spritam® manufactured by Aprecia pharmaceuticals in 2015. The precision and printing efficiency of 3D printing is strongly influenced by the dynamics of ink/binder jetting, which further depends on the ink's fluid properties. In this study, Computational Fluid Dynamics (CFD) has been utilized to study the drop formation process during inkjet-based 3D printing for piezoelectric and thermal printhead geometries using Volume of Fluid (VOF) method. To develop the CFD model commercial software ANSYS-Fluent was used. The developed CFD model was experimentally validated using drop watcher setup to record drop progression and drop velocity. During the study, water, Fujifilm model fluid, and Amitriptyline drug solutions were evaluated as the ink solutions. The drop properties such as drop volume, drop diameter, and drop velocity were examined in detail in response to change ink solution properties such as surface tension, viscosity, and density. A good agreement was observed between the experimental and simulation data for drop properties such as drop volume and drop velocity.
Collapse
Affiliation(s)
- Tanu Mehta
- Department of Pharmaceutical Sciences, University of Connecticut, USA
| | - Hossain Aziz
- Department of Pharmaceutical Sciences, University of Connecticut, USA
| | - Koyel Sen
- Department of Pharmaceutical Sciences, University of Connecticut, USA
| | - Shing-Yun Chang
- Department of Chemical and Biomolecular Engineering, University of Connecticut, USA; Institute of Materials Science, University of Connecticut, USA
| | | | - Anson W K Ma
- Department of Chemical and Biomolecular Engineering, University of Connecticut, USA; Institute of Materials Science, University of Connecticut, USA
| | - Bodhisattwa Chaudhuri
- Department of Pharmaceutical Sciences, University of Connecticut, USA; Department of Chemical and Biomolecular Engineering, University of Connecticut, USA; Institute of Materials Science, University of Connecticut, USA.
| |
Collapse
|
8
|
Macellari M, Schillaci A, Tanzini U, Trimarchi M, Quadrio M. An adjoint-based approach for the surgical correction of nasal septal deviations. Comput Biol Med 2024; 176:108566. [PMID: 38744016 DOI: 10.1016/j.compbiomed.2024.108566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 04/04/2024] [Accepted: 05/05/2024] [Indexed: 05/16/2024]
Abstract
Deviations of the septal wall are widespread anatomic anomalies of the human nose; they vary significantly in shape and location, and often cause the obstruction of the nasal airways. When severe, septal deviations need to be surgically corrected by ear-nose-throat (ENT) specialists. Septoplasty, however, has a low success rate, owing to the lack of suitable standardized clinical tools for assessing type and severity of obstructions, and for surgery planning. Moreover, the restoration of a perfectly straight septal wall is often impossible and possibly unnecessary. This paper introduces a procedure, based on advanced patient-specific Computational Fluid Dynamics (CFD) simulations, to support ENT surgeons in septoplasty planning. The method hinges upon the theory of adjoint-based optimization, and minimizes a cost function that indirectly accounts for viscous losses. A sensitivity map is computed on the mucosal wall to provide the surgeon with a simple quantification of how much tissue removal at each location would contribute to easing the obstruction. The optimization procedure is applied to three representative nasal anatomies, reconstructed from CT scans of patients affected by complex septal deviations. The computed sensitivity consistently identifies all the anomalies correctly. Virtual surgery, i.e. morphing of the anatomies according to the computed sensitivity, confirms that the characteristics of the nasal airflow improve significantly after small anatomy changes derived from adjoint-based optimization.
Collapse
Affiliation(s)
- Marcello Macellari
- Department of Aerospace Science and Technologies, Politecnico di Milano, Campus Bovisa, Milano 20156, Italy
| | - Andrea Schillaci
- Department of Aerospace Science and Technologies, Politecnico di Milano, Campus Bovisa, Milano 20156, Italy
| | - Umberto Tanzini
- Division of Head and Neck, Otorhinolaryngology unit, IRCCS San Raffaele Scientific Institute, Milano, Italy; School of Medicine, Vita-Salute San Raffaele University, Milano, Italy
| | - Matteo Trimarchi
- Department of Otolaryngology - Head and Neck Surgery, Ente Ospedaliero Cantonale, Ospedale Regionale di Lugano - Universita' della Svizzera Italiana, Lugano, Switzerland
| | - Maurizio Quadrio
- Department of Aerospace Science and Technologies, Politecnico di Milano, Campus Bovisa, Milano 20156, Italy.
| |
Collapse
|
9
|
Salehi N, Al-Gousous J, Hens B, Amidon GL, Ziff RM, Amidon GE. Comparative Evaluation of Dissolution Performance in a USP 2 Setup and Alternative Stirrers and Vessel Designs: A Systematic Computational Investigation. Mol Pharm 2024; 21:2406-2414. [PMID: 38639477 DOI: 10.1021/acs.molpharmaceut.3c01203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
The dissolution testing method described in the United States Pharmacopeia (USP) Chapter ⟨711⟩ is widely used for assessing the release of active pharmaceutical ingredients from solid dosage forms. However, extensive use over the years has revealed certain issues, including high experimental intervariability observed in specific formulations and the settling of particles in the dead zone of the vessel. To address these concerns and gain a comprehensive understanding of the hydrodynamic conditions within the USP 2 apparatus, computational fluid dynamic simulations have been employed in this study. The base design employed in this study is the 900 mL USP 2 vessel along with a paddle stirrer at a 50 rpm rotational speed. Additionally, alternative stirrer designs, including the hydrofoil, pitched blade, and Rushton impeller, are investigated. A comparison is also made between a flat-bottom tank and the USP round-bottom vessel of the same volume and diameter. Furthermore, this work examines the impact of various parameters, such as clearance distance (distance between the bottom of the impeller and bottom of the vessel), number of impeller blades, impeller diameter, and impeller attachment angle. The volume-average shear rate (Stv), fluid velocity (Utv), and energy dissipation rates (ϵtv) represent the key properties evaluated in this study. Comparing the USP2 design and systems with the same stirrer but flat-bottom vessel reveals more homogeneous mixing compared to the USP2 design. Analyzing fluid flow streamlines in different designs demonstrates that hydrofoil stirrers generate more suspension or upward movement of fluid compared to paddle stirrers. Therefore, when impellers are of a similar size, hydrofoil designs generate higher fluid velocities in the coning area. Furthermore, the angle of blade attachment to the hub influences the fluid velocity in the coning area in a way that the 60° angle design generates more suspension than the 45° angle design. The findings indicate that the paddle stirrer design leads to a heterogeneous shear rate and velocity distributions within the vessel compared with the other designs, suggesting suboptimal performance. These insights provide valuable guidance for the development of improved in vitro dissolution testing devices, emphasizing the importance of optimized design considerations to minimize hydrodynamic variability, enhance dissolution characterization, and reduce variability in dissolution test results. Ultimately, such advancements hold potential for improving in vitro-in vivo correlations in drug development.
Collapse
Affiliation(s)
- Niloufar Salehi
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
- Synthetic Molecule Design & Development, Lilly Technology Center, Eli Lilly and Company, Indianapolis, Indiana 46221, United States
| | - Jozef Al-Gousous
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg University Mainz, Mainz 55128, Germany
| | - Bart Hens
- Drug Product Design, Pfizer, Sandwich CT13 9NJ, U.K
| | - Gordon L Amidon
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Robert M Ziff
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Gregory E Amidon
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
| |
Collapse
|
10
|
Sadeghi T, Fatehi P, Pakzad L. Effect of Nasal Inhalation on Drug Particle Deposition and Size Distribution in the Upper Airway: With Soft Mist Inhalers. Ann Biomed Eng 2024; 52:1195-1212. [PMID: 38509413 DOI: 10.1007/s10439-023-03423-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 12/10/2023] [Indexed: 03/22/2024]
Abstract
Delivery of drugs to the lungs is commonly achieved using nasal and/or oral breathing-assisted techniques. The route of inhalation can substantially change the fate of inhaled droplets. The Respimat® Soft Mist™ Inhaler (SMI) is a commercially available efficient inhaler with 40-60% effectiveness. In the present study, we used computational fluid dynamics (CFD) with a custom setup to investigate the effect of a combined oral/nasal inhalation route on the SMI's regional droplet deposition, size distribution, and flow field. Our setup used a modified induction port (MIP) to mimic nasal inhalation inside the human respiratory tract. Six different oral/nasal flow rate ratios inside the MIP were applied (total flow rate of 30 l/min). An overall good agreement was achieved between simulation outcomes and in vitro results. Our results confirmed that the combined inhalation route affects the flow field, altering the MIP's droplet deposition and size distribution. The lowest depositional loss, mainly in the mouth area, was observed at oral/nasal flow rate ratios of O/N = 1 and O/N = 2 with 3% and 7.7% values, respectively. Droplets with a 2-5 µm diameter range showed the highest droplet mass inside the MIP at all combined flow rates. We observed less intense vortexes followed by a lower level of turbulent kinetic energy at the oral/nasal ratio of 1. Increasing the relative humidity (RH) at oral/nasal flow rate ratios of 0.07, 1, and 14 led to an increase in droplet deposition at the outlet of the MIP.
Collapse
Affiliation(s)
- Taha Sadeghi
- Department of Chemical Engineering, Lakehead University, 955 Oliver Road, Thunder Bay, ON, P7B 5E1, Canada
| | - Pedram Fatehi
- Department of Chemical Engineering, Lakehead University, 955 Oliver Road, Thunder Bay, ON, P7B 5E1, Canada
| | - Leila Pakzad
- Department of Chemical Engineering, Lakehead University, 955 Oliver Road, Thunder Bay, ON, P7B 5E1, Canada.
| |
Collapse
|
11
|
Abood MS, Hussain I. Ground effect of an inverted double element wing diffuser on a sedan car. Heliyon 2024; 10:e29435. [PMID: 38644812 PMCID: PMC11031749 DOI: 10.1016/j.heliyon.2024.e29435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 04/07/2024] [Accepted: 04/08/2024] [Indexed: 04/23/2024] Open
Abstract
The diffuser is a critical component in sports cars, enhancing aerodynamics by increasing downforce and reducing drag. Previous studies have focused on its dependence on diffuser incidence, height, and base pressure. The design of the car, particularly the rear end shape and the rear wing's presence, affect base pressure and the diffuser's performance. Previous studies have investigated the effects of diffuser geometry on aerodynamic performance, but the current study is the first to examine the relationship between the diffuser and the rear tires. It also provides specific and quantitative results on the impact of different diffuser design parameters on drag and downforce. The relationship between the rear tires and the double-element inverted wing diffuser using computational fluid dynamics (CFD) was investigated. This is an essential problem because the diffuser is a critical component of sports cars, and its design can significantly impact aerodynamic performance. CFD was used to simulate the flow of air around the car model. The CFD model was based on the Nissan Sunny (Versa) type Almera design, and the diffuser main element and flap wing angles were set at 4 and 15.5°, respectively. The flap gap, overlap distance, and wing ride height above the ground were varied to achieve an optimal aerodynamic design. The study found that the wing's ride height significantly influences the flow through the diffuser. The diffuser significantly impacts base pressure and downforce production. Increasing the ride height decreases base pressure, leading to an increase in downforce until a specific point near the car body, where downforce further increases. The study concluded that the best double-element diffuser design was selected based on lift-to-drag results and the allowable dimensions of the car, wing ride height, element gap, and overlap distances. Ultimately, the best diffuser wing design features a ride height of 154 mm, a gap distance of 10 mm, and an overlap of 5 mm. This design reduces drag by approximately 2.7 % and remarkably increases downforce ten times compared to the baseline car model.
Collapse
|
12
|
He W, Karmakar A, Kang J, Rowlands G, Schirmacher S, Méndez-Rojano R, Antaki J. In Vitro and In Silico Characterization of the Aggregation of Thrombi on Textured Ventricular Cannula. Ann Biomed Eng 2024:10.1007/s10439-024-03504-1. [PMID: 38679660 DOI: 10.1007/s10439-024-03504-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 03/25/2024] [Indexed: 05/01/2024]
Abstract
The unacceptably high stroke rate associated with HeartMate 3 ventricular assist device (VAD) without signs of adherent pump thrombosis is hypothesized to be the result of the emboli produced by the inflow cannula, that are ingested and ejected from the pump. This in vitro and numerical study aimed to emulate the surface features and supraphysiological shear of a ventricular cannula to provide insight into their effect on thrombogenesis. Human whole blood was perfused at calibrated flow rates in a microfluidic channel to achieve shear rates 1000-7500 s-1, comparable to that experienced on the cannula. The channel contained periodic teeth representative of the rough sintered surface of the HeartMate 3 cannula. The deposition of fluorescently labeled platelets was visualized in real time and analyzed with a custom entity tracking algorithm. Numerical simulations of a multi-constituent thrombosis model were performed to simulate laminar blood flow in the channel. The sustained growth of adherent platelets was observed in all shear conditions ( p < 0.05). However, the greatest deposition was observed at the lower shear rates. The location of deposition with respect to the microfluidic teeth was also found to vary with shear rate. This was confirmed by CFD simulation. The entity tracking algorithm revealed the spatial variation of instances of embolic events. This result suggests that the sintered surface of the ventricular cannula may engender unstable thrombi with a greater likelihood of embolization at supraphysiological shear rates.
Collapse
Affiliation(s)
- Wenxuan He
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Abhishek Karmakar
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Junhyuk Kang
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Grant Rowlands
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Samuel Schirmacher
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
| | | | - James Antaki
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA.
| |
Collapse
|
13
|
Sreekumar S, Chakrabarti S, Hewitt N, Mondol JD, Shah N. Performance Prediction and Optimization of Nanofluid-Based PV/T Using Numerical Simulation and Response Surface Methodology. Nanomaterials (Basel) 2024; 14:774. [PMID: 38727368 PMCID: PMC11085735 DOI: 10.3390/nano14090774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 04/11/2024] [Accepted: 04/25/2024] [Indexed: 05/12/2024]
Abstract
A numerical investigation was carried out in ANSYS Fluent® on a photovoltaic/thermal (PV/T) system with MXene/water nanofluid as heat transfer fluid (HTF). The interaction of different operating parameters (nanofluid mass fraction, mass flow rate, inlet temperature and incident radiation) on the output response of the system (thermal efficiency, electrical efficiency, thermal exergy efficiency, and electrical exergy efficiency) was studied using a predictive model generated using response surface methodology (RSM). The analysis of variance (ANOVA) method was used to evaluate the significance of input parameters affecting the energy and exergy efficiencies of the nanofluid-based PV/T system. The nanofluid mass flow rate was discovered to be having an impact on the thermal efficiency of the system. Electrical efficiency, thermal exergy efficiency, and electrical exergy efficiency were found to be greatly influenced by incident solar radiation. The percentage contribution of each factor on the output response was calculated. Input variables were optimized using the desirability function to maximize energy and exergy efficiency. The developed statistical model generated an optimum value for the mass flow rate (71.84 kgh-1), the mass fraction (0.2 wt%), incident radiation (581 Wm-2), and inlet temperature (20 °C). The highest overall energy and exergy efficiency predicted by the model were 81.67% and 18.6%, respectively.
Collapse
Affiliation(s)
- Sreehari Sreekumar
- Centre for Sustainable Technologies (CST), Belfast School of Architecture and the Built Environment, Ulster University, Belfast BT15 1ED, Northern Ireland, UK; (N.H.); (J.D.M.); (N.S.)
| | - Supriya Chakrabarti
- Nanotechnology and Integrated Bio-Engineering Centre (NIBEC), Ulster University, Belfast BT15 1ED, Northern Ireland, UK;
| | - Neil Hewitt
- Centre for Sustainable Technologies (CST), Belfast School of Architecture and the Built Environment, Ulster University, Belfast BT15 1ED, Northern Ireland, UK; (N.H.); (J.D.M.); (N.S.)
| | - Jayanta Deb Mondol
- Centre for Sustainable Technologies (CST), Belfast School of Architecture and the Built Environment, Ulster University, Belfast BT15 1ED, Northern Ireland, UK; (N.H.); (J.D.M.); (N.S.)
| | - Nikhilkumar Shah
- Centre for Sustainable Technologies (CST), Belfast School of Architecture and the Built Environment, Ulster University, Belfast BT15 1ED, Northern Ireland, UK; (N.H.); (J.D.M.); (N.S.)
| |
Collapse
|
14
|
Awad HH, Desouki M. Integrating physical experiments with computational fluid dynamics to transform mosque minarets into efficient solar chimneys. Sci Rep 2024; 14:9721. [PMID: 38678072 PMCID: PMC11055916 DOI: 10.1038/s41598-024-59589-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Accepted: 04/12/2024] [Indexed: 04/29/2024] Open
Abstract
This study explores the potential of repurposing mosque minarets as solar chimneys in hot arid regions to facilitate natural ventilation and diminish the reliance on energy-intensive cooling systems. Originating as a means to call the faithful to prayer, minarets have become iconic landmarks within Islamic cities. This research focuses on Cairo, Egypt, as a representative hot arid environment. The paper traces the evolution of the minaret, underscoring the variations in form that influence the experimental design. The investigation proceeded in two stages: the construction of physical mosque models with variably positioned minarets for laboratory testing, ensuring standardized measurements, followed by computational fluid dynamics (CFD) simulations for comparison. Findings indicate that mosque minarets can be effectively adapted for passive ventilation, with their performance significantly influenced by orientation and placement. This study concludes that traditional mosque minarets offer a viable, sustainable option for passive cooling in hot climates.
Collapse
Affiliation(s)
- Hesham H Awad
- Department of Architectural Engineering, Faculty of Engineering, Menoufeia University, Shebeen El-Kom, Egypt
| | - Mahmoud Desouki
- Department of Architectural Engineering, Nile Higher Institute for Engineering and Technology, Mansoura, Egypt.
| |
Collapse
|
15
|
Marzouk SA, Almehmadi FA, Aljabr A, Sharaf MA. Numerical and experimental investigation of heat transfer enhancement in double tube heat exchanger using nail rod inserts. Sci Rep 2024; 14:9637. [PMID: 38670963 PMCID: PMC11053124 DOI: 10.1038/s41598-024-59085-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 04/07/2024] [Indexed: 04/28/2024] Open
Abstract
The Double-tube heat exchanger (DTHX) is widely favored across various industries due to its compact size, low maintenance requirements, and ability to operate effectively in high-pressure applications. This study explores methods to enhance heat transfer within a DTHX using both experimental and numerical approaches, specifically by integrating a nail rod insert (NRI). A steel nails rod insert, 1000 mm in length, is introduced into the DTHX, which is subjected to turbulent flows characterized by Reynolds numbers ranging from 3200 to 5700. Three different pitches of NRI (100 mm, 50 mm, and 25 mm) are investigated. The results indicate a significant increase in the Nusselt (Nu) number upon the insertion of nail rods, with further improvements achievable by reducing the pitch length. Particularly noteworthy is the Nu number enhancement ratio for the 25 mm pitch NRI, which is 1.81-1.9 times higher than that for the plain tube. However, it is observed that pressure drop increases in all configurations with NRI due to heightened turbulence and obstruction by the NRI. Among the various pitch lengths, the 25 mm pitch exhibits the highest pressure drop values. Moreover, exergy efficiency is found to improve across all cases with NRI, corresponding to increased heat transfer, with the 25 mm pitch length showing a remarkable 128% improvement. Numerical analysis reveals that the novel insert enhances flow turbulence through the generation of secondary flows, thereby enhancing heat transfer within the DTHX. This study provides a comprehensive analysis, including temperature, velocity, and pressure drop distributions derived from numerical simulations.
Collapse
Affiliation(s)
- S A Marzouk
- Department of Mechanical Engineering, Faculty of Engineering, Kafrelsheikh University, Kafrelsheikh, 33511, Egypt.
| | - Fahad Awjah Almehmadi
- Department of Applied Mechanical Engineering, College of Applied Engineering, Muzahimiyah Branch, King Saud University, P.O. Box 800, 11421, Riyadh, Saudi Arabia.
| | - Ahmad Aljabr
- Department of Mechanical and Industrial Engineering, College of Engineering, Majmaah University, 11952, Al-Majmaah, Saudi Arabia
| | - Maisa A Sharaf
- Mechanical Engineering Dept, Faculty of Engineering, Damanhour University, Damanhour, 22511, Egypt
| |
Collapse
|
16
|
Sinharoy A, Lee GY, Chung CM. Process Intensification for Enhanced Fluoride Removal and Recovery as Calcium Fluoride Using a Fluidized Bed Reactor. Int J Mol Sci 2024; 25:4646. [PMID: 38731865 PMCID: PMC11083762 DOI: 10.3390/ijms25094646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 04/19/2024] [Accepted: 04/23/2024] [Indexed: 05/13/2024] Open
Abstract
This study explored the feasibility of fluoride removal from simulated semiconductor industry wastewater and its recovery as calcium fluoride using fluidized bed crystallization. The continuous reactor showed the best performance (>90% fluoride removal and >95% crystallization efficiency) at a calcium-to-fluoride ratio of 0.6 within the first 40 days of continuous operation. The resulting particle size increased by more than double during this time, along with a 36% increase in the seed bed height, indicating the deposition of CaF2 onto the silica seed. The SEM-EDX analysis showed the size and shape of the crystals formed, along with the presence of a high amount of Ca-F ions. The purity of the CaF2 crystals was determined to be 91.1% though ICP-OES analysis. Following the continuous experiment, different process improvement strategies were explored. The addition of an excess amount of calcium resulted in the removal of an additional 6% of the fluoride; however, compared to this single-stage process, a two-stage approach was found to be a better strategy to achieve a low effluent concentration of fluoride. The fluoride removal reached 94% with this two-stage approach under the optimum conditions of 4 + 1 h HRT combinations and a [Ca2+]/[F-] ratio of 0.55 and 0.7 for the two reactors, respectively. CFD simulation showed the impact of the inlet diameter, bottom-angle shape, and width-to-height ratio of the reactor on the mixing inside the reactor and the possibility of further improvement in the reactor performance by optimizing the FBR configuration.
Collapse
Affiliation(s)
| | | | - Chong-Min Chung
- Department of Environmental Science & Biotechnology, Jeonju University, Jeonju 55069, Republic of Korea; (A.S.); (G.-Y.L.)
| |
Collapse
|
17
|
Natarajan T, Singh-Gryzbon S, Chen H, Sadri V, Ruile P, Neumann FJ, Yoganathan AP, Dasi LP. Sensitivity of Post-TAVR Hemodynamics to the Distal Aortic Arch Anatomy: A High-Fidelity CFD Study. Cardiovasc Eng Technol 2024:10.1007/s13239-024-00728-z. [PMID: 38653932 DOI: 10.1007/s13239-024-00728-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 03/22/2024] [Indexed: 04/25/2024]
Abstract
PURPOSE Patient-specific simulations of transcatheter aortic valve (TAV) using computational fluid dynamics (CFD) often rely on assumptions regarding proximal and distal anatomy due to the limited availability of high-resolution imaging away from the TAV site and the primary research focus being near the TAV. However, the influence of these anatomical assumptions on computational efficiency and resulting flow characteristics remains uncertain. This study aimed to investigate the impact of different distal aortic arch anatomies-some of them commonly used in literature-on flow and hemodynamics in the vicinity of the TAV using large eddy simulations (LES). METHODS Three aortic root anatomical configurations with four representative distal aortic arch types were considered in this study. The arch types included a 90-degree bend, an idealized distal aortic arch anatomy, a clipped version of the idealized distal aortic arch, and an anatomy extruded along the normal of segmented anatomical boundary. Hemodynamic parameters both instantaneous and time-averaged such as Wall Shear Stress (WSS), and Oscillatory Shear Index (OSI) were derived and compared from high-fidelity CFD data. RESULTS While there were minor differences in flow and hemodynamics across the configurations examined, they were generally not significant within our region of interest i.e., the aortic root. The choice of extension type had a modest impact on TAV hemodynamics, especially in the vicinity of the TAV with variations observed in local flow patterns and parameters near the TAV. However, these differences were not substantial enough to cause significant deviations in the overall flow and hemodynamic characteristics. CONCLUSIONS The results suggest that under the given configuration and boundary conditions, the type of outflow extension had a modest impact on hemodynamics proximal to the TAV. The findings contribute to a better understanding of flow dynamics in TAV configurations, providing insights for future studies in TAV-related experiments as well as numerical simulations. Additionally, they help mitigate the uncertainties associated with patient-specific geometries, offering increased flexibility in computational modeling.
Collapse
Affiliation(s)
- Thangam Natarajan
- Department of Biomedical Engineering, Georgia Institute of Technology, 387 Technology Circle, Atlanta, GA, 30313-2412, USA
| | - Shelly Singh-Gryzbon
- Department of Biomedical Engineering, Georgia Institute of Technology, 387 Technology Circle, Atlanta, GA, 30313-2412, USA
- Department of Chemical Engineering, University of the West Indies, St.Augustine, Trinidad and Tobago
| | - Huang Chen
- Department of Biomedical Engineering, Georgia Institute of Technology, 387 Technology Circle, Atlanta, GA, 30313-2412, USA
| | - Vahid Sadri
- Department of Biomedical Engineering, Georgia Institute of Technology, 387 Technology Circle, Atlanta, GA, 30313-2412, USA
- Abbott Laboratories, 387 Technology Circle, Atlanta, GA, 30313-2412, USA
| | - Philipp Ruile
- Department of Cardiology and Angiology, Medical Center - University of Freiburg, and Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Franz-Josef Neumann
- Department of Cardiology and Angiology, Medical Center - University of Freiburg, and Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ajit P Yoganathan
- Department of Biomedical Engineering, Georgia Institute of Technology, 387 Technology Circle, Atlanta, GA, 30313-2412, USA
| | - Lakshmi P Dasi
- Department of Biomedical Engineering, Georgia Institute of Technology, 387 Technology Circle, Atlanta, GA, 30313-2412, USA.
| |
Collapse
|
18
|
Csippa B, Sándor L, Závodszky G, Szikora I, Paál G. Comparison of Flow Reduction Efficacy of Nominal and Oversized Flow Diverters Using a Novel Measurement-assisted in Silico Method. Clin Neuroradiol 2024:10.1007/s00062-024-01404-4. [PMID: 38652163 DOI: 10.1007/s00062-024-01404-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 03/07/2024] [Indexed: 04/25/2024]
Abstract
PURPOSE The high efficacy of flow diverters (FD) in the case of wide-neck aneurysms is well demonstrated, yet new challenges have arisen because of reported posttreatment failures and the growing number of new generation of devices. Our aim is to present a measurement-supported in silico workflow that automates the virtual deployment and subsequent hemodynamic analysis of FDs. In this work, the objective is to analyze the effects of FD deployment variability of two manufacturers on posttreatment flow reduction. METHODS The virtual deployment procedure is based on detailed mechanical calibration of the flow diverters, while the flow representation is based on hydrodynamic resistance (HR) measurements. Computational fluid dynamic simulations resulted in 5 untreated and 80 virtually treated scenarios, including 2 FD designs in nominal and oversized deployment states. The simulated aneurysmal velocity reduction (AMVR) is correlated with the HR values and deployment scenarios. RESULTS The linear HR coefficient and AMVR revealed a power-law relationship considering all 80 deployments. In nominal deployment scenarios, a significantly larger average AMVR was obtained (60.3%) for the 64-wire FDs than for 48-wire FDs (51.9%). In oversized deployments, the average AMVR was almost the same for 64-wire and 48-wire device types, 27.5% and 25.7%, respectively. CONCLUSION The applicability of our numerical workflow was demonstrated, also in large-scale hemodynamic investigations. The study revealed a robust power-law relationship between a HR coefficient and AMVR. Furthermore, the 64 wire configurations in nominal sizing produced a significantly higher posttreatment flow reduction, replicating the results of other in vitro studies.
Collapse
Affiliation(s)
- Benjamin Csippa
- Department of Hydrodynamic Systems, Faculty of Mechanical Engineering,, Budapest University of Technology and Economics, Műegyetem rkp 1-3, 1111, Budapest, Hungary.
| | - Levente Sándor
- Department of Hydrodynamic Systems, Faculty of Mechanical Engineering,, Budapest University of Technology and Economics, Műegyetem rkp 1-3, 1111, Budapest, Hungary
| | - Gábor Závodszky
- Department of Hydrodynamic Systems, Faculty of Mechanical Engineering,, Budapest University of Technology and Economics, Műegyetem rkp 1-3, 1111, Budapest, Hungary
- Faculty of Science, Informatics Institute, Computational Science Lab, University of Amsterdam, Amsterdam, The Netherlands
| | - István Szikora
- National Institute of Mental Health, Neurology, and Neurosurgery, Department of Neurointerventions, Budapest, Hungary
| | - György Paál
- Department of Hydrodynamic Systems, Faculty of Mechanical Engineering,, Budapest University of Technology and Economics, Műegyetem rkp 1-3, 1111, Budapest, Hungary
| |
Collapse
|
19
|
Zhao Q, Li R, Cao K, Yi M, Liu H. Influence of building spatial patterns on wind environment and air pollution dispersion inside an industrial park based on CFD simulation. Environ Monit Assess 2024; 196:427. [PMID: 38573508 DOI: 10.1007/s10661-024-12593-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 03/30/2024] [Indexed: 04/05/2024]
Abstract
The "spatial pattern-wind environment-air pollution" within building clusters is closely interconnected, where different spatial pattern parameters may have varying degrees of impact on the wind environment and pollutant dispersion. Due to the complex spatial structure within industrial parks, this complexity may lead to the accumulation and retention of air pollutants within the parks. Therefore, to alleviate the air pollution situation in industrial parks in China and achieve the circular transformation and construction of parks, this study takes Hefei Circular Economy Demonstration Park as the research object. The microscale Fluent model in computational fluid dynamics (CFD) is used to finely simulate the wind flow field and the diffusion process of pollutants within the park. The study analyzes the triad relationship and influence mechanism of "spatial pattern-wind environment-air pollution" within the park and studies the influence of different spatial pattern parameters on the migration and diffusion of pollutants. The results show a significant negative correlation between the content of pollutants and wind speed inside the industrial park. The better the wind conditions, the higher the air quality. The spatial morphology parameters of the building complex are the main influences on the condition of its internal wind environment. Building coverage ratio and degree of enclosure have a significant negative correlation with wind conditions. Maintaining them near 0.23 and 0.37, respectively, is favorable to the quality of the surrounding environment. Moreover, the average height of the building is positively correlated with the wind environment condition. The rate of transport and dissipation of pollutants gradually increases as the average building height reaches 16 m. Therefore, a reasonable building planning strategy and arrangement layout can effectively improve the wind environment condition inside the park, thus alleviating the pollutant retention situation. The obtained results serve as a theoretical foundation for optimizing morphological structure design within urban industrial parks.
Collapse
Affiliation(s)
- Qiang Zhao
- School of Environment and Energy Engineering, Anhui Jianzhu University, Hefei, 230601, China
- Anhui Institute of Carbon Emission Peak and Carbon Neutrality in Urban-Rural Development, Hefei, 230601, China
- Anhui Engineering and Technology Research Center of Smart City, Hefei, 230601, China
| | - Rui Li
- School of Environment and Energy Engineering, Anhui Jianzhu University, Hefei, 230601, China.
| | - Kaifa Cao
- Anhui Kechuang Zhongguang Technology Co., Ltd., Hefei, 230031, China
| | - Mingjian Yi
- School of Environment and Energy Engineering, Anhui Jianzhu University, Hefei, 230601, China
- Anhui Institute of Carbon Emission Peak and Carbon Neutrality in Urban-Rural Development, Hefei, 230601, China
- Anhui Engineering and Technology Research Center of Smart City, Hefei, 230601, China
| | - Hao Liu
- School of Environment and Energy Engineering, Anhui Jianzhu University, Hefei, 230601, China
| |
Collapse
|
20
|
Azimi S, Arzanpour S. Enhancing Inhalation Drug Delivery: A Comparative Study and Design Optimization of a Novel Valved Holding Chamber. J Biomech Eng 2024; 146:041002. [PMID: 38183225 DOI: 10.1115/1.4064436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 12/27/2023] [Indexed: 01/07/2024]
Abstract
This paper presents an innovative approach to the design optimization of valved holding chambers (VHCs), crucial devices for aerosol drug delivery. We present the design of an optimal cylindrical VHC body and introduce a novel valve based on particle impaction theory. The research combines computational simulations and physical experiments to assess the performance of various VHCs, with a special focus on the deposition patterns of medication particles within these devices. The methodology incorporates both experimental and simulation approaches to validate the reliability of the simulation. Emphasis is placed on the deposition patterns observed on the VHC walls and the classification of fine and large particles for salbutamol sulfate particles. The study reveals the superior efficacy of our valve design in separating particles compared to commercially available VHCs. In standard conditions, our valve design allows over 95% of particles under 7 μm to pass through while effectively filtering those larger than 8 μm. The optimized body design accomplishes a 60% particle mass flow fraction at the outlet and an average particle size reduction of 58.5%. When compared numerically in terms of size reduction, the optimal design outperforms the two commercially available VHCs selected. This study provides valuable insights into the optimization of VHC design, offering significant potential for improved aerosol drug delivery. Our findings demonstrate a new path forward for future studies, aiming to further optimize the design and performance of VHCs for enhanced pulmonary drug delivery.
Collapse
Affiliation(s)
- Shahab Azimi
- School of Mechatronic Systems Engineering, Simon Fraser University, 250 - 13450 102nd Avenue, Surrey, BC V3T 0A3, Canada
| | - Siamak Arzanpour
- School of Mechatronic Systems Engineering, Simon Fraser University, Room 4174, 250 - 13450 102nd Avenue, Surrey, BC V3T 0A3, Canada
| |
Collapse
|
21
|
Liao J, Misaki K, Uno T, Futami K, Nakada M, Sakamoto J. Determination of Significant Three-Dimensional Hemodynamic Features for Postembolization Recanalization in Cerebral Aneurysms Through Explainable Artificial Intelligence. World Neurosurg 2024; 184:e166-e177. [PMID: 38246531 DOI: 10.1016/j.wneu.2024.01.076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 01/12/2024] [Accepted: 01/13/2024] [Indexed: 01/23/2024]
Abstract
BACKGROUND Recanalization poses challenges after coil embolization in cerebral aneurysms. Establishing predictive models for postembolization recanalization is important for clinical decision making. However, conventional statistical and machine learning (ML) models may overlook critical parameters during the initial selection process. METHODS In this study, we automated the identification of significant hemodynamic parameters using a PointNet-based deep neural network (DNN), leveraging their three-dimensional spatial features. Further feature analysis was conducted using saliency mapping, an explainable artificial intelligence (XAI) technique. The study encompassed the analysis of velocity, pressure, and wall shear stress in both precoiling and postcoiling models derived from computational fluid dynamics simulations for 58 aneurysms. RESULTS Velocity was identified as the most pivotal parameter, supported by the lowest P value from statistical analysis and the highest area under the receiver operating characteristic curves/precision-recall curves values from the DNN model. Moreover, visual XAI analysis showed that robust injection flow zones, with notable impingement points in precoiling models, as well as pronounced interplay between flow dynamics and the coiling plane, were important three-dimensional features in identifying the recanalized aneurysms. CONCLUSIONS The combination of DNN and XAI was found to be an accurate and explainable approach not only at predicting postembolization recanalization but also at discovering unknown features in the future.
Collapse
Affiliation(s)
- Jing Liao
- Division of Transdisciplinary Sciences, Graduate School of Frontier Science Initiative, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Kouichi Misaki
- Department of Neurosurgery, Kanazawa University, Kanazawa, Ishikawa, Japan.
| | - Tekehiro Uno
- Department of Neurosurgery, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Kazuya Futami
- Department of Neurosurgery, Hokuriku Central Hospital, Oyabe, Toyama, Japan
| | - Mitsutoshi Nakada
- Department of Neurosurgery, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Jiro Sakamoto
- Division of Mechanical Science and Engineering, Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa, Ishikawa, Japan
| |
Collapse
|
22
|
Emmerling J, Vahaji S, Morton DAV, Fletcher DF, Inthavong K. Scale resolving simulations of the effect of glottis motion and the laryngeal jet on flow dynamics during respiration. Comput Methods Programs Biomed 2024; 247:108064. [PMID: 38382308 DOI: 10.1016/j.cmpb.2024.108064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/27/2023] [Accepted: 02/05/2024] [Indexed: 02/23/2024]
Abstract
BACKGROUND AND OBJECTIVE The movement of the respiratory walls has a significant impact on airflow through the respiratory tract. The majority of computational fluid dynamics (CFD) studies assume a static geometry which may not provide a realistic flow field. Furthermore, many studies use Reynolds Averaged Navier-Stokes (RANS) turbulence models that do not resolve turbulence structure. Combining the application of advanced scale-resolving turbulence models with moving respiratory walls using CFD will provide detailed insights into respiratory flow structures. METHODS This study simulated a complete breathing cycle involving inhalation and exhalation in a nasal cavity to trachea geometry that incorporated moving glottis walls. A second breathing cycle was simulated with static glottis walls for comparison. A recently developed hybrid RANS-LES turbulence model, the Stress-Blended Eddy Simulation (SBES), was incorporated to resolve turbulent flow structures in fine detail for both transient simulations. Transient results were compared with steady-state RANS simulations for the same respiratory geometry. RESULTS Glottis motion caused substantial effects on flow structure through the complete breathing cycle. Significant flow structure and velocity variations were observed due to glottal motion, primarily in the larynx and trachea. Resolved turbulence structures using SBES showed an intense mixing section in the glottis region during inhalation and in the nasopharynx during expiration, which was not present in the RANS simulations. CONCLUSION Transient simulations of a realistic breathing cycle uncovered flow structures absent in simulations with a constant flow rate. Furthermore, the incorporation of glottis motion impacted airflow characteristics that suggest rigid respiratory walls do not accurately describe respiratory flow. Future research in respiratory airflow should be conducted using transient scale-resolving models in conjunction with moving respiratory walls to capture flow structures in detail.
Collapse
Affiliation(s)
- Jake Emmerling
- School of Engineering, Deakin University, Waurn Ponds 3216, Australia
| | - Sara Vahaji
- Mechanical & Automotive Engineering, School of Engineering, RMIT University, Bundoora, Victoria 3083, Australia
| | - David A V Morton
- School of Engineering, Deakin University, Waurn Ponds 3216, Australia
| | - David F Fletcher
- School of Chemical and Biomolecular Engineering, University of Sydney, NSW 2006, Australia
| | - Kiao Inthavong
- Mechanical & Automotive Engineering, School of Engineering, RMIT University, Bundoora, Victoria 3083, Australia.
| |
Collapse
|
23
|
Poletti G, Ninarello D, Pennati G. Computational Analysis of the Effects of Fiber Deformation on the Microstructure and Permeability of Blood Oxygenator Bundles. Ann Biomed Eng 2024; 52:1091-1105. [PMID: 38349442 PMCID: PMC10940480 DOI: 10.1007/s10439-024-03446-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 01/07/2024] [Indexed: 03/16/2024]
Abstract
Mechanical loads on the polymeric fibers of oxygenating bundles are commonly present due to bundle press-fitting during device assembly and blood pressure load. However, computational fluid dynamics (CFD) simulations for fiber bundle optimization neglect possible changes in microstructure due to such deformations. The aim of this study is to investigate the impact of fiber deformability on bundle microstructure and fluid dynamics mainly in terms of permeability. Fibers from commercial mats typically used for blood oxygenators were mechanically tested and based on these experimental data, a material model was developed to simulate the structural deformations the fibers undergo under press-fitting and blood pressure loads. Then, CFD simulations were performed on deformed bundle repetitive units to investigate permeability under varying loading conditions. The effects of different bundle geometric parameters on the variation of bundle permeability due to press-fitting were evaluated. Bundle press-fitting results in significant changes in microstructure that are reflected in a bundle permeability more than halved for a 15% press-fitting. This impact on permeability is present in all the simulated fiber bundles and becomes more pronounced as the pitch between fibers and thus bundle porosity decreases. Instead, the analyses on pressurized bundle show only small deformations caused by pressure load, with permeability changes below 1%. While blood pressure effects could be neglected, bundle press-fitting turns out to have a significant impact on bundle microstructure and permeability. Neglecting such microstructure variations during CFD simulations could also lead to incorrect assessment of the local fluid dynamics within the bundle.
Collapse
Affiliation(s)
- Gianluca Poletti
- LaBS - Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy.
| | - Davide Ninarello
- LaBS - Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy
| | - Giancarlo Pennati
- LaBS - Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy
| |
Collapse
|
24
|
Li X, Xiao Y, Liu X, Huang H, Xiang J, Chen W, Mao H, Huang Z. Optimization of up-flow anaerobic sludge blanket second-layer influent distribution structure. Environ Technol 2024; 45:1683-1695. [PMID: 36409524 DOI: 10.1080/09593330.2022.2150567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 11/11/2022] [Indexed: 06/16/2023]
Abstract
ABSTRACTA parametric model of the second-layer influent distributor is proposed to increase the reaction efficiency of the up-flow anaerobic sludge blanket. The impacts on the flow efficiency of the main parameters, including the length of distribution pipe, that is, the cylinder radius r1, the eccentricity of the nozzle e, and the number of nozzles n1, are investigated. The optimal parameter combination of the second-layer influent distributoris obtained by single factor analysis and orthogonal analysis. Then the two-layer distributor combination model, including the bottom influent distributor and the second-layer influent distributor, is established and the simulations are conducted to study the effect of the two-layer distributor on flow inside the reactor. The simulation results show that the proposed two-layer distributor can achieve a higher mixture efficiency than the single distributor.
Collapse
Affiliation(s)
- Xinxin Li
- School of Mechanical Engineering, Guangxi University, Nanning, People's Republic of China
| | - Yan'an Xiao
- School of Mechanical Engineering, Guangxi University, Nanning, People's Republic of China
| | - Xi Liu
- Guangxi Bossco Environmental Protection Technology Co., Ltd, Nanning, People's Republic of China
| | - He Huang
- School of Mechanical Engineering, Guangxi University, Nanning, People's Republic of China
| | - Jiangshu Xiang
- School of Mechanical Engineering, Guangxi University, Nanning, People's Republic of China
| | - Wenxian Chen
- School of Mechanical Engineering, Guangxi University, Nanning, People's Republic of China
| | - Hanling Mao
- School of Mechanical Engineering, Guangxi University, Nanning, People's Republic of China
| | - Zhenfeng Huang
- School of Mechanical Engineering, Guangxi University, Nanning, People's Republic of China
| |
Collapse
|
25
|
Ramaekers MJFG, van der Vlugt IB, Westenberg JJM, Perinajová R, Lamb HJ, Wildberger JE, Kenjereš S, Schalla S. Flow patterns in ascending aortic aneurysms: Determining the role of hypertension using phase contrast magnetic resonance and computational fluid dynamics. Comput Biol Med 2024; 172:108310. [PMID: 38508054 DOI: 10.1016/j.compbiomed.2024.108310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 02/22/2024] [Accepted: 03/12/2024] [Indexed: 03/22/2024]
Abstract
Thoracic aortic aneurysm (TAA) is a local dilation of the thoracic aorta. Although universally used, aneurysm diameter alone is a poor predictor of major complications such as rupture. There is a need for better biomarkers for risk assessment that also reflect the aberrant flow patterns found in TAAs. Furthermore, hypertension is often present in TAA patients and may play a role in progression of aneurysm. The exact relation between TAAs and hypertension is poorly understood. This study aims to create a numerical model of hypertension in the aorta by using computational fluid dynamics. First, a normotensive state was simulated in which flow and resistance were kept unaltered. Second, a hypertensive state was modeled in which blood inflow was increased by 30%. Third, a hypertensive state was modeled in which the proximal and peripheral resistances and capacitance parameters from the three-element Windkessel boundary condition were adjusted to mimic an increase in resistance of the rest of the cardiovascular system. One patient with degenerative TAA and one healthy control were successfully simulated at hypertensive states and were extensively analyzed. Furthermore, three additional TAA patients and controls were simulated to validate our method. Hemodynamic variables such as wall shear stress, oscillatory shear index, endothelial cell activation potential (ECAP), vorticity and helicity were studied to gain more insight on the effects of hypertension on flow patterns in TAAs. By comparing a TAA patient and a control at normotensive state at peak-systole, helicity and vorticity were found to be lower in the TAA patient throughout the entire domain. No major changes in flow and flow derived quantities were observed for the TAA patient and control when resistance was increased. When flow rate was increased, regions with high ECAP values were found to reduce in TAA patients in the aneurysm region which could reduce the risk of thrombogenesis. Thus, it may be important to assess cardiac output in patients with TAA.
Collapse
Affiliation(s)
- M J F G Ramaekers
- Departments of Cardiology and Radiology and Nuclear Medicine, Maastricht University Medical Center +, Maastricht, The Netherlands; Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands
| | - I B van der Vlugt
- Department of Chemical Engineering, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - J J M Westenberg
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - R Perinajová
- Department of Chemical Engineering, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands; J.M. Burgerscentrum Research School for Fluid Mechanics, Delft, The Netherlands
| | - H J Lamb
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - J E Wildberger
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands; Department of Radiology and Nuclear Medicine, Maastricht University Medical Center +, Maastricht, The Netherlands
| | - S Kenjereš
- Department of Chemical Engineering, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands; J.M. Burgerscentrum Research School for Fluid Mechanics, Delft, The Netherlands.
| | - S Schalla
- Departments of Cardiology and Radiology and Nuclear Medicine, Maastricht University Medical Center +, Maastricht, The Netherlands; Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands
| |
Collapse
|
26
|
Mattusch AM, Schaldach G, Bartsch J, Thommes M. Intrinsic dissolution rate modeling for the pharmacopoeia apparatus rotating disk compared to flow channel method. Pharm Dev Technol 2024; 29:281-290. [PMID: 38501605 DOI: 10.1080/10837450.2024.2329115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 03/07/2024] [Indexed: 03/20/2024]
Abstract
For a solid understanding of drug characteristics, in vitro measurement of the intrinsic dissolution rate is important. Hydrodynamics are often emphasized as the decisive parameter influencing the dissolution. In this study, experiments and computational fluid dynamic (CFD) simulations showed that the mixing behavior in the rotating disc apparatus causes an inhomogeneous flow field and a systematic error in the calculation of the intrinsic dissolution rate. This error is affected by both the experimental time and the velocity. Due to the rotational movement around the tablet center, commonly utilized in pharmacopeia methods, a broad variance is present with regard to the impact of fluid velocity on individual particles of the specimen surface. As this is significantly reduced in the case of uniform overflow, the flow channel is recommended for investigating the dissolution behavior. It is shown that rotating disc measurements can be compared with flow channel measurements after adjusting the measured data for the rotating disc based on a proposed, representative Reynolds number and a suggested apparatus-dependent correction factor. Additionally, modeling the apparatus-independent intrinsic dissolution rate for different temperatures in the rotating disc apparatus is possible using the adapted Levich's equation.
Collapse
Affiliation(s)
- Amelie M Mattusch
- Department of Biochemical and Chemical Engineering, TU Dortmund University, Germany
| | - Gerhard Schaldach
- Department of Biochemical and Chemical Engineering, TU Dortmund University, Germany
| | - Jens Bartsch
- Department of Biochemical and Chemical Engineering, TU Dortmund University, Germany
| | - Markus Thommes
- Department of Biochemical and Chemical Engineering, TU Dortmund University, Germany
| |
Collapse
|
27
|
Maxa J, Šabacká P, Mazal J, Neděla V, Binar T, Bača P, Talár J, Bayer R, Čudek P. The Impact of Nozzle Opening Thickness on Flow Characteristics and Primary Electron Beam Scattering in an Environmental Scanning Electron Microscope. Sensors (Basel) 2024; 24:2166. [PMID: 38610377 PMCID: PMC11014117 DOI: 10.3390/s24072166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 03/13/2024] [Accepted: 03/26/2024] [Indexed: 04/14/2024]
Abstract
This paper describes the methodology of combining experimental measurements with mathematical-physics analyses in the investigation of flow in the aperture and nozzle. The aperture and nozzle separate the differentially pumped chamber from the specimen chamber in an environmental scanning electron microscope (ESEM). Experimental measurements are provided by temperature and pressure sensors that meet the demanding conditions of cryogenic temperature zones and low pressures. This aperture maintains the required pressure difference between the chambers. Since it separates the large pressure gradient, critical flow occurs on it and supersonic gas flow with the characteristic properties of critical flow in the state variables occurs behind it. As a primary electron beam passes through the differential pumped chamber and the given aperture, the aperture is equipped with a nozzle. The shape of the nozzle strongly influences the character of the supersonic flow. The course of state variables is also strongly influenced by this shape; thus, it affects the number of collisions the primary beam's electrons have with gas molecules, and so the resulting image. This paper describes experimental measurements made using sensors under laboratory conditions in a specially created experimental chamber. Then, validation using mathematical-physical analysis in the Ansys Fluent system is described.
Collapse
Affiliation(s)
- Jiří Maxa
- Institute of Scientific Instruments of the CAS, Královopolská 147, 612 64 Brno, Czech Republic
- Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 10, 616 00 Brno, Czech Republic (R.B.)
| | - Pavla Šabacká
- Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 10, 616 00 Brno, Czech Republic (R.B.)
| | - Jan Mazal
- Faculty of Military Robotics, University of Defence, 662 10 Brno, Czech Republic
| | - Vilém Neděla
- Institute of Scientific Instruments of the CAS, Královopolská 147, 612 64 Brno, Czech Republic
| | - Tomáš Binar
- Faculty of Military Leadership, University of Defence, 662 10 Brno, Czech Republic (J.T.)
| | - Petr Bača
- Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 10, 616 00 Brno, Czech Republic (R.B.)
| | - Jaroslav Talár
- Faculty of Military Leadership, University of Defence, 662 10 Brno, Czech Republic (J.T.)
| | - Robert Bayer
- Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 10, 616 00 Brno, Czech Republic (R.B.)
| | - Pavel Čudek
- Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 10, 616 00 Brno, Czech Republic (R.B.)
| |
Collapse
|
28
|
Chillón SA, Fernandez-Gamiz U, Zulueta E, Ugarte-Anero A, Blanco JM. Numerical performance of CO 2 accumulation and droplet dispersion from a cough inside a hospital lift under different ventilation strategies. Sci Rep 2024; 14:6843. [PMID: 38514758 PMCID: PMC10957917 DOI: 10.1038/s41598-024-57425-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 03/18/2024] [Indexed: 03/23/2024] Open
Abstract
The impact of mechanical ventilation on airborne diseases is not completely known. The recent pandemic of COVID-19 clearly showed that additional investigations are necessary. The use of computational tools is an advantage that needs to be included in the study of designing safe places. The current study focused on a hospital lift where two subjects were included: a healthy passenger and an infected one. The elevator was modelled with a fan placed on the middle of the ceiling and racks for supplying air at the bottom of the lateral wall. Three ventilation strategies were evaluated: a without ventilation case, an upwards-blowing exhausting fan case and a downwards-blowing fan case. Five seconds after the elevator journey began, the infected person coughed. For the risk assessment, the CO2 concentration, droplet removal performance and dispersion were examined and compared among the three cases. The results revealed some discrepancies in the selection of an optimal ventilation strategy. Depending on the evaluated parameter, downward-ventilation fan or no ventilation strategy could be the most appropriate approach.
Collapse
Affiliation(s)
- Sergio A Chillón
- Energy Engineering Department, School of Engineering of Vitoria-Gasteiz, University of the Basque Country, UPV/EHU, Nieves Cano 12, 01006, Vitoria-Gasteiz, Araba, Spain
| | - Unai Fernandez-Gamiz
- Energy Engineering Department, School of Engineering of Vitoria-Gasteiz, University of the Basque Country, UPV/EHU, Nieves Cano 12, 01006, Vitoria-Gasteiz, Araba, Spain.
| | - Ekaitz Zulueta
- Automatic and Simulation Department, University of the Basque Country, UPV/EHU, Nieves Cano 12, 01006, Vitoria-Gasteiz, Araba, Spain
| | - Ainara Ugarte-Anero
- Energy Engineering Department, School of Engineering of Vitoria-Gasteiz, University of the Basque Country, UPV/EHU, Nieves Cano 12, 01006, Vitoria-Gasteiz, Araba, Spain
| | - Jesus Maria Blanco
- Energy Engineering Department, School of Engineering, University of the Basque Country (UPV/EHU), Plaza Ingeniero Torres Quevedo, Building 1, 48013, Bilbao, Spain
| |
Collapse
|
29
|
Alizadeh A, Jasim DJ, Sohrabi N, Ahmed M, Ameer SA, Ibrahim SM, Dabis HK, Hussein AA, Sultan AJ. Using shock generator for the fuel mixing of the extruded single 4-lobe nozzle at supersonic combustion chamber. Sci Rep 2024; 14:6405. [PMID: 38493238 PMCID: PMC10944517 DOI: 10.1038/s41598-024-57103-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 03/14/2024] [Indexed: 03/18/2024] Open
Abstract
The importance of the fuel injection configuration on the propulsion efficiency of high-speed vehicles is apparent. In this article, the use of an annular extruded 4-lobe nozzle for the injection of fuel jet in a supersonic combustor of a scramjet engine in the existence of a shock generator is examined. The main aim of this study is to obtain the efficient jet arrangement for efficient fuel mixing inside the engine of hypersonic vehicles. A numerical approach is used to model the supersonic air stream and cross-jet flow with the SST turbulence model. The role of nozzle altitude and internal air jet on the fuel mixing of the hydrogen within the high-speed domain are disclosed. The importance of the horseshoe vortex and counter-rotating vortex on the fuel distribution is also presented. Our results show that the usage of a coaxial jet instead of an annular jet would increase fuel mixing by more than 40% in the combustion chamber.
Collapse
Affiliation(s)
- As'ad Alizadeh
- Department of Civil Engineering, College of Engineering, Cihan University-Erbil, Erbil, Iraq.
- Department of Mechanical Engineering, College of Engineering, Urmia University, Urmia, Iran.
| | - Dheyaa J Jasim
- Department of Petroleum Engineering, Al-Amarah University College, Maysan, Iraq
| | - Neaman Sohrabi
- Department of Mechanical and Mechatronics Engineering, Southern Illinois University, Edwardsville, IL, 62026, USA
| | - Mohsen Ahmed
- Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam, 31441, Eastern Province, Kingdom of Saudi Arabia
| | - S Abdul Ameer
- Department of Automobile Engineering, College of Engineering, Al-Musayab University of Babylon, Hillah, Iraq
| | | | | | - Ali Adhab Hussein
- Department of Medical Laboratory Technics, Al-Zahrawi University College, Karbala, Iraq
| | - Abbas J Sultan
- Department of Chemical Engineering, University of Technology-Iraq, Baghdad, Iraq
- Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, MO, 65409-1230, USA
| |
Collapse
|
30
|
Jayakumar SS, Subramaniam IP, Stanislaus Arputharaj B, Solaiappan SK, Rajendran P, Lee IE, Madasamy SK, Gnanasekaran RK, Karuppasamy A, Raja V. Design, control, aerodynamic performances, and structural integrity investigations of compact ducted drone with co-axial propeller for high altitude surveillance. Sci Rep 2024; 14:6330. [PMID: 38491057 PMCID: PMC10943011 DOI: 10.1038/s41598-024-54174-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 02/09/2024] [Indexed: 03/18/2024] Open
Abstract
Compact multi-rotor unmanned aerial vehicles (UAVs) can be operated in many challenging environmental conditions. In case the UAV requires certain considerations in designing like lightweight, efficient propulsion system and others depending upon the application, the hybrid UAV comes into play when the usual UAV types cannot be sufficient to meet the requirements. The propulsion system for the UAV was selected to be coaxial rotors because it has a high thrust-to-weight ratio and to increase the efficiency of the propulsion system, a unique propeller was proposed to achieve higher thrust. The proposed propeller was uniquely designed by analyzing various airfoil sections under different Reynolds's number using X-Foil tool to obtain the optimum airfoil section for the propellers. Since the design with duct increases efficiency, the Hybrid UAV presented in this paper has the modified novel convergent-divergent (C-D)-based duct which is a simplified model of a conventional C-D duct. The yawing and rolling maneuverings of the UAV could be achieved by the thrust vectoring method so that the design is simpler from a structural and mechanical perspective. The use of UAVs has risen in recent years, especially compact UAVs, which can be applied for applications like surveillance, detection and inspection, and monitoring in a narrow region of space. The design of the UAV is modeled in CATIA, and its further performance enactment factors are picked from advanced computational simulations relayed bottom-up approach. The predominant computational fluid dynamics (CFD) and fluid structure interaction (FSI) investigations are imposed and optimized through Computational Analyses using Ansys Workbench 17.2, which includes analysis of structural behaviour of various alloys, CFRP and GFRP based composite materials. From the structural analysis Titanium alloy came out to be the best performing materials among the others by having lower total deformation and other parameters such as normal and equivalent stress. The dynamics control response is obtained using MATLAB Simulink. The validations are carried out on the propeller using a thrust stand for CFD and on the duct through a high-jet facility for structural outcomes to meet the expected outcome.
Collapse
Affiliation(s)
- Shyam Sundar Jayakumar
- Department of Aeronautical Engineering, Kumaraguru College of Technology, Coimbatore, Tamil Nadu, 641049, India
| | - Indira Prasanth Subramaniam
- Department of Aeronautical Engineering, Kumaraguru College of Technology, Coimbatore, Tamil Nadu, 641049, India
| | - Beena Stanislaus Arputharaj
- Department of Research and Innovation, Saveetha School of Engineering, SIMATS, Chennai, Tamil Nadu, 602105, India
| | - Senthil Kumar Solaiappan
- Department of Aeronautical Engineering, Kumaraguru College of Technology, Coimbatore, Tamil Nadu, 641049, India
| | - Parvathy Rajendran
- School of Aerospace Engineering, Universiti Sains Malaysia, 14300, Nibong Tebal, Penang, Malaysia
| | - It Ee Lee
- Faculty of Engineering, Multimedia University, 63100, Cyberjaya, Selangor D. E., Malaysia.
| | - Senthil Kumar Madasamy
- Department of Aeronautical Engineering, Kumaraguru College of Technology, Coimbatore, Tamil Nadu, 641049, India
| | - Raj Kumar Gnanasekaran
- Department of Aeronautical Engineering, Kumaraguru College of Technology, Coimbatore, Tamil Nadu, 641049, India
| | - Arunkumar Karuppasamy
- Department of Aeronautical Engineering, MLR Institute of Technology, Hyderabad, Telangana, India
| | - Vijayanandh Raja
- Department of Aeronautical Engineering, Kumaraguru College of Technology, Coimbatore, Tamil Nadu, 641049, India
| |
Collapse
|
31
|
Aderaw H, Nallamothu RB. Modelling and simulation of fuel tank with increased capacity and improving its location for better stability of three wheeled vehicle. Heliyon 2024; 10:e26697. [PMID: 38444483 PMCID: PMC10912235 DOI: 10.1016/j.heliyon.2024.e26697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 02/17/2024] [Accepted: 02/19/2024] [Indexed: 03/07/2024] Open
Abstract
In the automotive industry, the fuel tank is an essential component of the vehicle. It is; designed as an integral part of the fuel system to transport the fuel and deliver it to the engine via the fuel filter and fuel pump. In Ethiopia, it is observed that due to the smaller fuel tank of three-wheeled vehicles, more frequent visits to fuel stations result in a lot of time being wasted waiting in long queues at fuel stations. In addition, the current location of the fuel tank causes some stability problems. Subsequently, the method, location, installation techniques and stability analysis of the three-wheeled vehicle are carried out. This study includes a new design of fuel tanks for three-wheeled vehicles in which the capacity is doubled and the rollover stability; of the vehicle is maintained. The SOLIDWORKS software and the CFD software ANSYS FLUENT for the sloshing analysis were used for the modeling of this work. The CFD results of the comparative sloshing analysis of partially filled (50% level) fuel tanks with and without baffles are performed; and conclusions are drawn. It is concluded that a baffle plate for the fuel tank offers the greatest advantage in reducing the effects of sloshing. The newly developed part is mounted on the underside of the passenger seat. A bottom-mounted fuel tank optimizes the vehicle's center of gravity, as the height of the vehicle's center of gravity is lowered by 30 mm. This increases the rollover safety of the vehicle. According to the analysis, the mileage of the filled existing and new tanks is 136 km and 272 km respectively. To refuel once, the driver waits an average of 5 h and works about two days for the existing tank and four days for the new tank.
Collapse
Affiliation(s)
- Haileyesus Aderaw
- Department of Mechanical Engineering, School of Mechanical Chemical and Materials Engineering, Adama Science and Technology University, Adama, Ethiopia
| | - Ramesh Babu Nallamothu
- Department of Mechanical Engineering, School of Mechanical Chemical and Materials Engineering, Adama Science and Technology University, Adama, Ethiopia
| |
Collapse
|
32
|
Mereke NB, Ancha VR, Hendrick P. Numerical modeling and CFD simulation of diffuser augmented dual vertical axis hydrokinetic Banki-Michell turbine. Heliyon 2024; 10:e26970. [PMID: 38468972 PMCID: PMC10926066 DOI: 10.1016/j.heliyon.2024.e26970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 02/20/2024] [Accepted: 02/22/2024] [Indexed: 03/13/2024] Open
Abstract
Hydrokinetic Banki turbines present an affordable, technically feasible, environmentally friendly technology. Their construction without requiring more expensive structures like diversion weirs, canals, forebay, and penstock, makes their initial investment much lower than commonly used horizontal Banki turbine of the same capacity. The possibility to install in the existing canals for Ultra Low Head applications is the additional motivating factor for this research. The system studied includes two Banki runners without internal shafts mounted vertically side by side surrounded by nozzle and diffuser structures. In the first scenario, Nozzle and then the Nozzle-diffuser augmented structures were separately studied to enhance the output of the runner for ultra-low head application, and the effects of each on the speed, pressure, and power output were analyzed. For the case of commonly used Banki, without nozzle and diffuser augmentation the speed for Ultra Low Head was minimum and determined to be 344 rpm, which is far below the recommended value of 800 rpm for safe operation at a flow rate of 1 m^3/s. In view of this, in the present study the enhanced speed on account of improvement was found to be 850 rpm and 1025 rpm for the design without and with diffuser assemblies respectively. Besides, the performance is seen to be improved by 7.6% with the diffuser as compared with the one without diffuser assembly. Detailed simulation results are presented and discussed: 3D ANSYS-FLUENT optimization result provided optimum number of blades for each runner to be 19 and with the optimum throat width in both cases as 202 mm. On account of the lack of any results reported so far for this innovative geometry, validation of the simulated results was carried out with reported results for the dual horizontal axis Banki turbines with good agreement.
Collapse
Affiliation(s)
- Nebiyu Bogale Mereke
- Faculty of Mechanical Engineering, Jimma University Institute of Technology, Jimma, 378, Ethiopia
- Université Libre de Bruxelles, Aero-Thermo-Mechanics Department, Avenue F.D. Roosevelt 50, CP 165/41, 1050, Brussels, Belgium
| | - Venkata Ramayya Ancha
- Faculty of Mechanical Engineering, Jimma University Institute of Technology, Jimma, 378, Ethiopia
| | - Patrick Hendrick
- Université Libre de Bruxelles, Aero-Thermo-Mechanics Department, Avenue F.D. Roosevelt 50, CP 165/41, 1050, Brussels, Belgium
| |
Collapse
|
33
|
Teklemariyem DA, Yimer ET, Ancha VR, Zeru BA. Parametric study of an empty diffuser geometric parameters and shape for a wind turbine using CFD analysis. Heliyon 2024; 10:e26782. [PMID: 38455570 PMCID: PMC10918161 DOI: 10.1016/j.heliyon.2024.e26782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 02/20/2024] [Indexed: 03/09/2024] Open
Abstract
This research examines the optimal 3D geometric parameters and shape of empty diffusers to enhance the mass flow rate of the HAWT rotor plane using a detailed parametric study. Previous works have investigated the use of diffusers to augment turbine power output; however, different curvature surfaces and the effects of all associated angles have not been considered for a thorough evaluation. This work mainly focuses on analyzing the effect of opening angles (2° to 22°), inlet shroud angles (8° to 24°), flange height ratios, flange angles (0° and 15°), and shape of the diffuser as well as flanges on velocity, pressure at the diffuser entry, and through the diffuser section at a wind speed of 4.5 m/s. At an inlet-shroud angle of 24° and an opening angle of 8°, with a diffuser flange height-throat diameter ratio of 0.3, the system achieved an 82.9% increase in flowrate. The diffuser with an inlet shroud-side lower stepped flange showed an optimum velocity of 9.12 m/s (maximum) and 8.2 m/s (average), resulting in a 102.66% and 82.2% increase in velocity, respectively. The percentage increase in velocity of the present study is 92.61%, compared with the previous maximum increase in rate of 53.8%, and then an increase in velocity of 38.81% was obtained. The optimum speed occurred at 0.175 m from the inlet section of the diffuser, indicating where the turbine should best be located. The CFD results from this work were validated with experimental data from the literature, showing a good agreement between the two. Integrated diffuser-turbine system simulation and experimental work with field tests are recommended as a way forward.
Collapse
Affiliation(s)
| | - Eshetu Tadesse Yimer
- Jimma Insitute of Technology, Thermal Energy Systems, P.O.Box 378, Jimma, Ethiopia
| | | | - Balewgize Amare Zeru
- Jimma Insitute of Technology, Thermal Energy Systems, P.O.Box 378, Jimma, Ethiopia
| |
Collapse
|
34
|
Ashrafee A, Yashfe SMS, Khan NS, Islam MT, Azam MG, Arafat MT. Design of experiment approach to identify the dominant geometrical feature of left coronary artery influencing atherosclerosis. Biomed Phys Eng Express 2024; 10:035008. [PMID: 38430572 DOI: 10.1088/2057-1976/ad2f59] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 03/01/2024] [Indexed: 03/04/2024]
Abstract
Background and Objective. Coronary artery geometry heavily influences local hemodynamics, potentially leading to atherosclerosis. Consequently, the unique geometrical configuration of an individual by birth can be associated with future risk of atherosclerosis. Although current researches focus on exploring the relationship between local hemodynamics and coronary artery geometry, this study aims to identify the order of influence of the geometrical features through systematic experiments, which can reveal the dominant geometrical feature for future risk assessment.Methods. According to Taguchi's method of design of experiment (DoE), the left main stem (LMS) length (lLMS), curvature (kLMS), diameter (dLMS) and the bifurcation angle between left anterior descending (LAD) and left circumflex (LCx) artery (αLAD-LCx) of two reconstructed patient-specific left coronary arteries (LCA) were varied in three levels to create L9 orthogonal array. Computational fluid dynamic (CFD) simulations with physiological boundary conditions were performed on the resulting eighteen LCA models. Average helicity intensity (h2) and relative atheroprone area (RAA) of near-wall hemodynamic descriptors were analyzed.Results. The proximal LAD (LADproximal) was identified to be the most atheroprone region of the left coronary artery due to higherh2,large RAA of time averaged wall shear stress (TAWSS < 0.4 Pa), oscillatory shear index (OSI ∼ 0.5) and relative residence time (RRT > 4.17 Pa-1). In both patient-specific cases, based onh2and TAWSS,dlmsis the dominant geometric parameter while based on OSI and RRT,αLAD-LCxis the dominant one influencing hemodynamic condition in proximal LAD (p< 0.05). Based on RRT, the rank of the geometrical factors is:αLAD-LCx>dLMS>lLMS>kLMS, indicating thatαLAD-LCxis the most dominant geometrical factor affecting hemodynamics at proximal LAD which may influence atherosclerosis.Conclusion. The proposed identification of the rank of geometrical features of LCA and the dominant feature may assist clinicians in predicting the possibility of atherosclerosis, of an individual, long before it will occur. This study can further be translated to be used to rank the influence of several arterial geometrical features at different arterial locations to explore detailed relationships between the arterial geometrical features and local hemodynamics.
Collapse
Affiliation(s)
- Adiba Ashrafee
- Department of Biomedical Engineering, Bangladesh University of Engineering and Technology (BUET), Dhaka - 1205, Bangladesh
| | - Syed Muiz Sadat Yashfe
- Department of Biomedical Engineering, Bangladesh University of Engineering and Technology (BUET), Dhaka - 1205, Bangladesh
| | - Nusrat S Khan
- Department of Biomedical Engineering, Bangladesh University of Engineering and Technology (BUET), Dhaka - 1205, Bangladesh
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, United States of America
| | - Md Tariqul Islam
- Department of Radiology and Imaging, Sheikh Hasina National Institute of Burn & Plastic Surgery, Dhaka - 1205, Bangladesh
| | - M G Azam
- Department of Cardiology, National Institute of Cardiovascular Diseases (NICVD), Dhaka - 1207, Bangladesh
| | - M Tarik Arafat
- Department of Biomedical Engineering, Bangladesh University of Engineering and Technology (BUET), Dhaka - 1205, Bangladesh
| |
Collapse
|
35
|
Guo N, Lin J, Wu J. Simulation on two-phase refrigerant compression in the cylinder of rotary compressors using CFD method. Sci Rep 2024; 14:6075. [PMID: 38480850 PMCID: PMC10937932 DOI: 10.1038/s41598-024-56856-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 03/12/2024] [Indexed: 03/17/2024] Open
Abstract
The two-phase compression process in the rotary compressor often occurs, such as defrosting and startup processes, which has a significant impact on the performance and reliability of air conditioning systems. In this paper, the CFD simulations predicting the two-phase refrigerant compression process in the compressor cylinder are conducted using the commercial software ANSYS Fluent. The dynamic mesh for the fluid domain and phase change model for the refrigerant are considered in the simulation. Effects of initial liquid volume fraction, refrigerant type and compressor type on the two-phase compression characteristics using R290 as refrigerant are carried out. Variations of the pressure, temperature, gas fraction distribution and evaporation rate in the cylinder are discussed. The results show that most liquid accumulates near the leakage gap and the bottom of the compression chamber during the two-phase compression process. The peak pressure during the two-phase compression decreases with the increase of the liquid volume fraction. The evaporation rate of R32 in the cylinder is much higher than that of R290. The maximum pressure of the reciprocating compressor is 2.26 times higher than that of the rotary compressor.
Collapse
Affiliation(s)
- Nini Guo
- College of Mechanical Engineering, Quzhou University, Quzhou, 324000, China
| | - Jie Lin
- College of Mechanical Engineering, Quzhou University, Quzhou, 324000, China.
| | - Jianhua Wu
- School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, 710049, China
| |
Collapse
|
36
|
Dankano A, Prather R, Lozinski B, Divo E, Kassab A, DeCampli W. Tailoring left ventricular assist device cannula implantation using coupled multi-scale multi-objective optimization. Med Eng Phys 2024; 125:104124. [PMID: 38508801 DOI: 10.1016/j.medengphy.2024.104124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 01/17/2024] [Accepted: 02/15/2024] [Indexed: 03/22/2024]
Abstract
BACKGROUND The frequent occurrence of thromboembolic cerebral events continues to limit the widespread implementation of Ventricular Assist Devices (VAD) despite continued advancements in VAD design and anti-coagulation treatments. Recent studies point to the optimal positioning of the outflow graft (OG) as a potential mitigator of post implantation thromboembolism. OBJECTIVE This study aims to examine the tailoring of the OG implantation orientation with the goal of minimizing the number of thrombi reaching the cerebral vessels by means of a formal shape optimization scheme incorporated into a multi-scale hemodynamics analysis. METHODS A 3-D patient-specific computational fluid dynamics model is loosely coupled in a two-way manner to a 0-D lumped parameter model of the peripheral circulation. A Lagrangian particle-tracking scheme models and tracks thrombi as non-interacting solid spheres. The loose coupling between CFD and LPM is integrated into a geometric shape optimization scheme which aims to optimize an objective function that targets a drop in cerebral embolization, and an overall reduction in particle residence times. RESULTS The results elucidate the importance of OG anastomosis orientation and placement particularly in the case that studied particle release from the OG, as a fivefold decrease in cerebral embolization was observed between the optimal and non-optimal implantations. Another case considered particle release from the ventricle and aortic root walls, in which optimal implantation was achieved with a shallow insertion angle. Particle release from all three origins was investigated in the third case, demonstrating that the optimal configurations were generally characterized by VAD flow directed along the central lumen of the aortic arch. Because optimal configurations depended on the anatomic origin of the thrombus, it is important to determine, in clinical studies, the most likely sites of thrombus formation in VAD patients.
Collapse
Affiliation(s)
- Abubakar Dankano
- Department of Mechanical and Aerospace Engineering, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL 32816, United States.
| | - Ray Prather
- Arnold Palmer Children's Hospital, 92 West Miller St, Orlando, FL 32806, United States
| | - Blake Lozinski
- Department of Mechanical and Aerospace Engineering, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL 32816, United States
| | - Eduardo Divo
- Department of Mechanical Engineering, Embry-Riddle Aeronautical University, 600 South Clyde Morris Blvd, Daytona Beach, FL 32114, United States
| | - Alain Kassab
- Department of Mechanical and Aerospace Engineering, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL 32816, United States
| | - William DeCampli
- College of Medicine, University of Central Florida, Arnold Palmer Children's Hospital, 92 West Miller St, Orlando, FL 32806, United States
| |
Collapse
|
37
|
Wickramarachchi A, Gregory SD, Burrell AJC, Khamooshi M. Flow characterization of Maquet and Bio-Medicus multi-stage drainage cannulae during venoarterial extracorporeal membrane oxygenation. Comput Biol Med 2024; 171:108135. [PMID: 38373368 DOI: 10.1016/j.compbiomed.2024.108135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 01/15/2024] [Accepted: 02/12/2024] [Indexed: 02/21/2024]
Abstract
BACKGROUND Drainage cannulae extract blood from a patient during venoarterial extracorporeal membrane oxygenation (VA ECMO), a treatment that temporarily supports patients undergoing severe heart and/or lung dysfunction. Currently, the two most commonly used multi-stage drainage cannulae are manufactured by Maquet and Bio-Medicus, but their designs vary in many aspects which impacts the generated flow dynamics. Therefore, this study aimed to use computational fluid dynamics (CFD) to explore the flow characteristics of the aforementioned cannulae and their impact on complications such as thrombosis. METHODS The Maquet and Bio-Medicus cannulae were 3D modelled within a patient-specific geometry of the venous vasculature taken from a computed tomography scan of a patient undergoing VA ECMO. A drainage flow rate of 4 L/min was assigned to each cannula. Lastly, a stress blended eddy simulation turbulence model was employed to resolve bulk flow turbulence. RESULTS The proximal row of side holes in both cannulae generated high intensity counter-rotating vortices, thus generating supraphysiological shear. These proximal rows were also responsible for the majority of flow extraction in both cannulae (>1.6 L/min). Despite identical simulation settings, each cannulae had differing impacts on global flow dynamics. For instance, the Bio-Medicus model produced a total stagnant blood volume of 25.6 ml, compared to 17.8 ml the Maquet cannula, thereby increasing the risk of thrombosis. CONCLUSIONS Overall, our results demonstrate that differences in design clearly impact flow dynamics and risk of complications. Therefore, further work in optimizing cannula design may be beneficial to prevent harmful flow characteristics.
Collapse
Affiliation(s)
- Avishka Wickramarachchi
- Cardio-Respiratory Engineering and Technology Laboratory, Department of Mechanical and Aerospace Engineering, Monash University, 631 Blackburn Road, Clayton, VIC, Australia.
| | - Shaun D Gregory
- Cardio-Respiratory Engineering and Technology Laboratory, Department of Mechanical and Aerospace Engineering, Monash University, 631 Blackburn Road, Clayton, VIC, Australia
| | - Aidan J C Burrell
- Department of Intensive Care, Alfred Hospital, 55 Commercial Road, Melbourne, VIC, Australia; Australian and New Zealand Intensive Care Research Centre, Monash University, Melbourne, VIC, Australia
| | - Mehrdad Khamooshi
- Cardio-Respiratory Engineering and Technology Laboratory, Department of Mechanical and Aerospace Engineering, Monash University, 631 Blackburn Road, Clayton, VIC, Australia
| |
Collapse
|
38
|
Li H, Shatarah M. Operator learning for urban water clarification hydrodynamics and particulate matter transport with physics-informed neural networks. Water Res 2024; 251:121123. [PMID: 38241806 DOI: 10.1016/j.watres.2024.121123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/01/2024] [Accepted: 01/08/2024] [Indexed: 01/21/2024]
Abstract
Computational fluid dynamics (CFD) can be a powerful tool for higher-fidelity water infrastructure planning and design. Despite decades of development and demonstration over a wide range of water systems such as clarification basins, activated sludge processes, ozone contactors, etc., CFD remains primarily used in academic research, with limited application in civil and environmental engineering practice. This limitation is contributed by its higher computational cost and demand for specialized user skills. This, however, need not be the case, if a robust and efficient surrogate model can be developed from CFD simulations and independently deployed for engineering purposes. Leveraging the emerging scientific machine learning (ML) techniques of physics-informed ML and operator learning, this study develops a composite neural network (CPNN) for learning the flow hydrodynamics and particulate matter (PM) transport and fate in clarification systems. The CPNN consists of a deep operator network (DeepONet) as an encoder and a physics-informed neural network (PINN) as a decoder. In contrast to common "black box" and lumped ML approaches, the developed CPNN directly incorporates physics principles into its architecture. Furthermore, the CPNN is designed for process-resolved and operator learning, enabling it to predict spatial hydrodynamics and PM concentration distribution (i.e., contours) across different basin geometrics and loading conditions. Compared to CFD simulation, the developed CPNN model has significantly higher computational efficiency (∼ milliseconds) while demonstrating robust predictive capability. For predicting basin hydrodynamics across 10,000 test cases, the trained CPNN model achieves an R2 above 0.8 for 66.4% of cases and an R2 above 0.4 for 89.2% of cases. A similar performance is also demonstrated by the CPNN in predicting basin PM concentration. Further investigation reveals that basin geometrics that trigger bi-modal flow solutions can be particularly challenging for ML. Additionally, this study visualizes the dependency of basin hydrodynamics and PM concentration on basin geometrics and loading conditions, providing valuable insights for optimizing basin configuration. Lastly, the potentials and benefits of web-based applications, e.g., DeepXtorm, as a user-friendly interface for the developed CPNN model is discussed. This study represents the initial step toward achieving real-time higher-fidelity water infrastructure planning, design, optimization, and regulation.
Collapse
Affiliation(s)
- Haochen Li
- Water Infrastructure Laboratory, Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, USA.
| | - Mohamed Shatarah
- Water Infrastructure Laboratory, Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, USA
| |
Collapse
|
39
|
Gazo Hanna E, Younes K, Roufayel R, Khazaal M, Fajloun Z. Engineering innovations in medicine and biology: Revolutionizing patient care through mechanical solutions. Heliyon 2024; 10:e26154. [PMID: 38390063 PMCID: PMC10882044 DOI: 10.1016/j.heliyon.2024.e26154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 01/24/2024] [Accepted: 02/08/2024] [Indexed: 02/24/2024] Open
Abstract
The overlap between mechanical engineering and medicine is expanding more and more over the years. Engineers are now using their expertise to design and create functional biomaterials and are continually collaborating with physicians to improve patient health. In this review, we explore the state of scientific knowledge in the areas of biomaterials, biomechanics, nanomechanics, and computational fluid dynamics (CFD) in relation to the pharmaceutical and medical industry. Focusing on current research and breakthroughs, we provide an overview of how these fields are being used to create new technologies for medical treatments of human patients. Barriers and constraints in these fields, as well as ways to overcome them, are also described in this review. Finally, the potential for future advances in biomaterials to fundamentally change the current approach to medicine and biology is also discussed.
Collapse
Affiliation(s)
- Eddie Gazo Hanna
- College of Engineering and Technology, American University of the Middle East, Egaila, 54200, Kuwait
| | - Khaled Younes
- College of Engineering and Technology, American University of the Middle East, Egaila, 54200, Kuwait
| | - Rabih Roufayel
- College of Engineering and Technology, American University of the Middle East, Egaila, 54200, Kuwait
| | - Mickael Khazaal
- École Supérieure des Techniques Aéronautiques et de Construction Automobile, ISAE-ESTACA, France
| | - Ziad Fajloun
- Faculty of Sciences 3, Department of Biology, Lebanese University, Campus Michel Slayman Ras Maska, 1352, Tripoli, Lebanon
- Laboratory of Applied Biotechnology (LBA3B), Azm Center for Research in Biotechnology and Its Applications, EDST, Lebanese University, 1300, Tripoli, Lebanon
| |
Collapse
|
40
|
García-Salaberri PA, Zenyuk IV. A general-purpose tool for modeling multifunctional thin porous media ( POREnet): From pore network to effective property tensors. Heliyon 2024; 10:e26253. [PMID: 38404803 PMCID: PMC10884887 DOI: 10.1016/j.heliyon.2024.e26253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 02/01/2024] [Accepted: 02/08/2024] [Indexed: 02/27/2024] Open
Abstract
POREnet, a novel approach to model effective properties of thin porous media, TPM, is presented. The methodology allows the extraction of local effective property tensors by volume averaging from discrete pore networks, PNs, built on the tessellated continuum space of a TPM. The gradient theorem is used to describe 3D transport in bulk tessellated space, providing an appropriate metric to normalize network fluxes. Implemented effective transport properties include diffusivity, permeability, solid-phase conductivity, and entry capillary pressure and contact angle under two-phase conditions, considering multi-component materials with several solid phases and local contact resistances. Calculated property tensors can be saved on 3D image stacks, where interfacial and sub-CV scale features can be added before exporting data to CFD meshes for simulation. Overall, POREnet provides a general-purpose, versatile methodology for modeling TPM in an ample range of conditions within a single CFD framework. Among other advantages, coupling of PN and continuum models at TPM-channel interfaces is simplified, interfacial contact resistances can be included using robin boundary conditions, and transient multiphysics simulations can be implemented more easily using CFD. The code is tested against a miscellaneousness of examples extracted from electrochemical applications.
Collapse
Affiliation(s)
- Pablo A. García-Salaberri
- Department of Thermal and Fluids Engineering, Universidad Carlos III de Madrid, Leganés 28911, Spain
| | - Iryna V. Zenyuk
- Department of Chemical & Biomolecular Engineering, National Fuel Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| |
Collapse
|
41
|
Hazan Shenberger S, Avrahami I. The Effect of Mechanical Circulatory Support on Blood Flow in the Ascending Aorta: A Combined Experimental and Computational Study. Bioengineering (Basel) 2024; 11:238. [PMID: 38534512 DOI: 10.3390/bioengineering11030238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 02/11/2024] [Accepted: 02/22/2024] [Indexed: 03/28/2024] Open
Abstract
Percutaneous mechanical circulatory support (MCS) devices are designed for short-term treatment in cases of acute decompensated heart failure as a bridge to transplant or recovery. Some of the known complications of MCS treatments are related to their hemodynamics in the aorta. The current study investigates the effect of MCS on the aortic flow. The study uses combined experimental and numerical methods to delineate complex flow structures. Particle image velocimetry (PIV) is used to capture the vortical and turbulent flow characteristics in a glass model of the human aorta. Computational fluid dynamics (CFD) analyses are used to complete the 3D flow in the aorta. Three specific MCS configurations are examined: a suction pump with a counterclockwise (CCW) rotating impeller, a suction pump with a clockwise (CW) rotating impeller, and a discharge pump with a straight jet. These models were examined under varying flow rates (1-2.5 L/min). The results show that the pump configuration strongly influences the flow in the thoracic aorta. The rotating impeller of the suction pump induces a dominant swirling flow in the aorta. The swirling flow distributes the incoming jet and reduces the turbulent intensity near the aortic valve and in the aorta. In addition, at high flow rates, the local vortices formed near the pump are washed downstream toward the aortic arch. Specifically, an MCS device with a CCW rotating impeller induces a non-physiological CCW helical flow in the descending aorta (which is opposite to the natural helical flow), while CW swirl combines better with the natural helical flow.
Collapse
Affiliation(s)
- Sapir Hazan Shenberger
- Department of Mechanical Engineering and Mechatronics, Ariel University, Ariel 40700, Israel
| | - Idit Avrahami
- Department of Mechanical Engineering and Mechatronics, Ariel University, Ariel 40700, Israel
| |
Collapse
|
42
|
Xiao D, Yan C, Desheng S. Study of cooling experiment and simulation for edible oil storage. Sci Rep 2024; 14:4588. [PMID: 38409412 PMCID: PMC10897485 DOI: 10.1038/s41598-024-55337-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/22/2024] [Indexed: 02/28/2024] Open
Abstract
This paper proposes a refrigerant cooling method using an inner tube in a storage tank to improve the cooling performance and thermal uniformity during the storing of edible oil. With a prototype of an oil tank in Central Grain Reserve of Zhenjiang, the experimental oil tank was built in a scale of 50:1. Both natural and manual cooling experiments were carried out for the experimental tank. The manual cooling process involved two supplying modes for the refrigerant tube (top and bottom) and four different refrigerant temperatures (10 ℃, 12 ℃, 14 ℃, 16 ℃). The experimental results show that, compared with natural cooling, manual cooling can effectively reduce the temperature difference and thermal stratification between upper and lower layers. The temperature difference is 6.79 ℃, 1.93 ℃, and 3.67 ℃ for the natural cooling, manual top supplying, and manual bottom supplying mode, respectively. Furthermore, for the two manual modes, the cooling efficiency of bottom supplying is 21.4% higher than that of the top supplying, and the average oil temperature drops by 0.8-1 ℃. Based on experimental results, different working conditions (20, 40, and 60 ml/s) were simulated to determine the optimal flow rate for bottom supplying mode. The simulation results indicate that the low flow rate (20 ml/s) corresponds to the best thermal uniformity, and the maximum temperature has no obvious change under different flow rate conditions. Therefore, it is not necessary to increase the flow rate to improve cooling efficiency considering the rising energy consumption.
Collapse
Affiliation(s)
- Du Xiao
- Henan University of Technology, Zhengzhou, 450001, People's Republic of China
| | - Chen Yan
- Henan University of Technology, Zhengzhou, 450001, People's Republic of China.
| | - Sun Desheng
- Henan Polytechnic, Zhengzhou, 450018, People's Republic of China
| |
Collapse
|
43
|
Kilikevičienė K, Kačianauskas R, Rimša V, Kilikevičius A. Agglomeration of particulate matter in chimneys using acoustic flow. Heliyon 2024; 10:e25306. [PMID: 38327408 PMCID: PMC10847651 DOI: 10.1016/j.heliyon.2024.e25306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 01/18/2024] [Accepted: 01/24/2024] [Indexed: 02/09/2024] Open
Abstract
The emission of micrometer-sized particulate matter on an industrial scale is causing increasing environmental concern about air pollution. Numerous industries and research communities need help to reduce micrometer-sized pollutants in the atmosphere. The current research investigates the acoustic agglomeration of particulate matter through a combination of experimental and numerical methods. Acoustic agglomeration is a process that involves using acoustic waves to influence the movement of particles in the air. Acoustic agglomeration operates by facilitating particle collision and simplifying the formation of agglomerates that are later removed through filtration. This article is focused on research on acoustic pre-processing with the aim of reducing atmospheric pollution caused by toxic combustion products. The capture of fine silica particles with diameters ranging from 0.3 to 10 μm, emitted through the chimneys of industrial enterprises, can be considered a significant technological innovation. The experimental part of the current research is conducted using a newly developed experimental bench. The assembly comprises the following key components: a wind tunnel, a particle dosing device, the agglomeration camera, and a particle concentration measurement device on the edge of the bench. A loudspeaker was used to evaluate the effect of sound pressure in the frequency range of 500-3000 Hz. A comprehensive CFD study of the particles was conducted, which included analysis of the boundary layer, facilitating a better understanding of the behavior of the particles and its potential to agglomerate. An experimental study of particle agglomeration, using an acoustic field with a frequency range of 500-3000 Hz, demonstrated the effectiveness of particle agglomeration of different diameters. The efficacy of particle agglomeration is up to 80 % when the sound pressure values were 129-135 dB; the highest efficiency was found at excitation frequencies of 1500 and 3000 Hz, respectively.
Collapse
Affiliation(s)
- Kristina Kilikevičienė
- Institute of Mechanical Science, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Rimantas Kačianauskas
- Institute of Mechanical Science, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Vytautas Rimša
- Department of Aviation Technologies, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Artūras Kilikevičius
- Institute of Mechanical Science, Vilnius Gediminas Technical University, Vilnius, Lithuania
| |
Collapse
|
44
|
Sasidharan A, Velamati RK, Mohammad A, Benaissa S. Mathematical modelling of a single tethered aerostat using longitudinal stability derivatives. Sci Rep 2024; 14:3697. [PMID: 38355935 PMCID: PMC10866963 DOI: 10.1038/s41598-024-53851-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 02/06/2024] [Indexed: 02/16/2024] Open
Abstract
Lighter-than-air (LTA) aerial vehicles such as airships and aerostats can be found in various strategic and commercial applications, primarily due to their capability to hover and stealth. The mathematical model of these vehicles helps in understanding their complex dynamics and designing and developing proper stabilisation systems for them. Stability derivatives have been used for developing mathematical models for heavier-than-air aerial vehicles since their introduction. This paper presents a methodology to develop a mathematical model of an aerostat based on stability derivatives. One of the major contributions of this study is the estimation of aerostat's added mass terms expressed as longitudinal stability derivatives due to acceleration of the longitudinal motion variables. A longitudinally decoupled linear mathematical model of a single-tethered aerostat using stability derivatives is investigated in this study. A computational fluid dynamics (CFD)-based analysis of the 3D model of the vehicle is used to obtain the stability derivatives. The methodology presented considers the aerostat and tether models separately before coupling them to create the full model. The stability derivative analysis is carried out using ANSYS Fluent, and the coupled tethered aerostat model is investigated using MATLAB 2020. The negative pitch angle of the aerostat is caused by the selection of the pitching centre as the aerostat centre of volume instead of the tether confluence point. The tension force on the tether, which is proportional to the wind velocity, and aerostat velocity components are found to be stabilised within 200-400 s.
Collapse
Affiliation(s)
- Anoop Sasidharan
- Department of Electrical and Electronics Engineering, Amrita Vishwa Vidyapeetham, Amritapuri, India
| | - Ratna Kishore Velamati
- Department of Mechanical Engineering, Amrita School of Engineering, Amrita Vishwa Vidyapeetham, Coimbatore, India
| | - Akram Mohammad
- Department of Aerospace Engineering, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Sabrina Benaissa
- Department of Sciences and Technology, Faculty of Technology, University of Batna 2, Batna, Algeria.
- Laboratory LPEA, University of Batna 1, Batna, Algeria.
| |
Collapse
|
45
|
Avraham M, Krayden A, Ashkar H, Aronin D, Stolyarova S, Blank T, Shlenkevitch D, Nemirovsky Y. A Novel Miniature and Selective CMOS Gas Sensor for Gas Mixture Analysis-Part 4: The Effect of Humidity. Micromachines (Basel) 2024; 15:264. [PMID: 38398992 PMCID: PMC10892996 DOI: 10.3390/mi15020264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 02/06/2024] [Accepted: 02/08/2024] [Indexed: 02/25/2024]
Abstract
This is the fourth part of a study presenting a miniature, combustion-type gas sensor (dubbed GMOS) based on a novel thermal sensor (dubbed TMOS). The TMOS is a micromachined CMOS-SOI transistor, which acts as the sensing element and is integrated with a catalytic reaction plate, where ignition of the gas takes place. The GMOS measures the temperature change due to a combustion exothermic reaction. The controlling parameters of the sensor are the ignition temperature applied to the catalytic layer and the increased temperature of the hotplate due to the released power of the combustion reaction. The solid-state device applies electrical parameters, which are related to the thermal parameters. The heating is applied by Joule heating with a resistor underneath the catalytic layer while the signal is monitored by the change in voltage of the TMOS sensor. Voltage, like temperature, is an intensive parameter, and one always measures changes in such parameters relative to a reference point. The reference point for both parameters (temperature and voltage) is the blind sensor, without any catalytic layer and hence where no reaction takes place. The present paper focuses on the study of the effect of humidity upon performance. In real life, the sensors are exposed to environmental parameters, where humidity plays a significant role. Humidity is high in storage rooms of fruits and vegetables, in refrigerators, in silos, in fields as well as in homes and cars. This study is significant and innovative since it extends our understanding of the performance of the GMOS, as well as pellistor sensors in general, in the presence of humidity. The three main challenges in simulating the performance are (i) how to define the operating temperature based on the input parameters of the heater voltage in the presence of humidity; (ii) how to measure the dynamics of the temperature increase during cyclic operation at a given duty cycle; and (iii) how to model the correlation between the operating temperature and the sensing response in the presence of humidity. Due to the complexity of the 3D analysis of packaged GMOS, and the many aspects of humidity simultanoesuly affecting performane, advanced simulation software is applied, incorporating computational fluid dynamics (CFD). The simulation and experimental data of this study show that the GMOS sensor can operate in the presence of high humidity.
Collapse
Affiliation(s)
- Moshe Avraham
- Electrical and Computer Engineering Department, Technion—Israel Institute of Technology, Haifa 3200003, Israel; (M.A.); (A.K.); (H.A.); (D.A.); (S.S.); (T.B.)
| | - Adir Krayden
- Electrical and Computer Engineering Department, Technion—Israel Institute of Technology, Haifa 3200003, Israel; (M.A.); (A.K.); (H.A.); (D.A.); (S.S.); (T.B.)
| | - Hanin Ashkar
- Electrical and Computer Engineering Department, Technion—Israel Institute of Technology, Haifa 3200003, Israel; (M.A.); (A.K.); (H.A.); (D.A.); (S.S.); (T.B.)
| | - Dan Aronin
- Electrical and Computer Engineering Department, Technion—Israel Institute of Technology, Haifa 3200003, Israel; (M.A.); (A.K.); (H.A.); (D.A.); (S.S.); (T.B.)
| | - Sara Stolyarova
- Electrical and Computer Engineering Department, Technion—Israel Institute of Technology, Haifa 3200003, Israel; (M.A.); (A.K.); (H.A.); (D.A.); (S.S.); (T.B.)
| | - Tanya Blank
- Electrical and Computer Engineering Department, Technion—Israel Institute of Technology, Haifa 3200003, Israel; (M.A.); (A.K.); (H.A.); (D.A.); (S.S.); (T.B.)
| | | | - Yael Nemirovsky
- Electrical and Computer Engineering Department, Technion—Israel Institute of Technology, Haifa 3200003, Israel; (M.A.); (A.K.); (H.A.); (D.A.); (S.S.); (T.B.)
| |
Collapse
|
46
|
Alotaibi H, Abeykoon C, Soutis C, Jabbari M. Infusion Simulation of Graphene-Enhanced Resin in LCM for Thermal and Chemo-Rheological Analysis. Materials (Basel) 2024; 17:806. [PMID: 38399057 PMCID: PMC10890079 DOI: 10.3390/ma17040806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/03/2024] [Accepted: 02/04/2024] [Indexed: 02/25/2024]
Abstract
The present numerical study proposes a framework to determine the heat flow parameters-specific heat and thermal conductivity-of resin-graphene nanoplatelets (GNPs) (modified) as well as non-modified resin (with no GNPs). This is performed by evaluating the exothermic reaction which occurs during both the filling and post-filling stages of Liquid Composite Moulding (LCM). The proposed model uses ANSYS Fluent to solve the Stokes-Brinkman (momentum and mass), energy, and chemical species conservation equations to a describe nano-filled resin infusion, chemo-rheological changes, and heat release/transfer simultaneously on a Representative Volume Element (RVE). The transient Volume-of-Fluid (VOF) method is employed to track free-surface propagation (resin-air interface) throughout the computational domain. A User-Defined Function (UDF) is developed together with a User-Defined Scaler (UDS) to incorporate the heat generation (polymerisation), which is added as an extra source term into the energy equation. A separate UDF is used to capture intra-tow (microscopic) flow by adding a source term into the momentum equation. The numerical findings indicate that the incorporation of GNPs can accelerate the curing of the resin system due to the high thermal conductivity of the nanofiller. Furthermore, the model proves its capability in predicting the specific heat and thermal conductivity of the modified and non-modified resin systems utilising the computed heat of reaction data. The analysis shows an increase of ∼15% in the specific heat and thermal conductivity due to different mould temperatures applied (110-170 °C). This, furthermore, stresses the fact that the addition of GNPs (0.2 wt.%) improves the resin-specific heat by 3.68% and thermal conductivity by 58% in comparison to the non-modified thermoset resin. The numerical findings show a satisfactory agreement with and in the range of experimental data available in the literature.
Collapse
Affiliation(s)
- Hatim Alotaibi
- Department of Mechanical, Aerospace and Civil Engineering, The University of Manchester, Manchester M13 9PL, UK
- Institute of Earth and Space Science, King Abdulaziz City for Science and Technology, Riyadh 12354, Saudi Arabia
| | - Chamil Abeykoon
- Department of Materials, The University of Manchester, Manchester M13 9PL, UK
- Aerospace Research Institute, The University of Manchester, Manchester M13 9PL, UK
| | - Constantinos Soutis
- Department of Materials, The University of Manchester, Manchester M13 9PL, UK
- Aerospace Research Institute, The University of Manchester, Manchester M13 9PL, UK
| | - Masoud Jabbari
- School of Mechanical Engineering, University of Leeds, Leeds LS2 9JT, UK
| |
Collapse
|
47
|
Segalerba E, Dini Ciacci G, Quadrio M, Pralits JO. On the comparison between pre- and post-surgery nasal anatomies via computational fluid dynamics. Biomech Model Mechanobiol 2024; 23:305-314. [PMID: 37902893 PMCID: PMC10902155 DOI: 10.1007/s10237-023-01776-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 09/21/2023] [Indexed: 11/01/2023]
Abstract
Nasal breathing difficulties (NBD) are widespread and difficult to diagnose; the failure rate of their surgical corrections is high. Computational fluid dynamics (CFD) enables diagnosis of NBD and surgery planning, by comparing a pre-operative (pre-op) situation with the outcome of virtual surgery (post-op). An equivalent comparison is involved when considering distinct anatomies in the search for the functionally normal nose. Currently, this comparison is carried out in more than one way, under the implicit assumption that results are unchanged, which reflects our limited understanding of the driver of the respiratory function. The study describes how to set up a meaningful comparison. A pre-op anatomy, derived via segmentation from a CT scan, is compared with a post-op anatomy obtained via virtual surgery. State-of-the-art numerical simulations for a steady inspiration carry out the comparison under three types of global constraints, derived from the field of turbulent flow control: a constant pressure drop (CPG) between external ambient and throat, a constant flow rate (CFR) through the airways and a constant power input (CPI) from the lungs can be enforced. A significant difference in the quantities of interest is observed depending on the type of comparison. Global quantities (flow rate, pressure drop and nasal resistance) as well as local ones are affected. The type of flow forcing affects the outcome of the comparison between pre-op and post-op anatomies. Among the three available options, we argue that CPG is the least adequate. Arguments favouring either CFR or CPI are presented.
Collapse
Affiliation(s)
- Eric Segalerba
- Department of Civil, Chemical and Environmental Engineering, University of Genova, Via Montallegro, 1, 16145, Genoa, Italy
| | - Gabriele Dini Ciacci
- Department of Aerospace Sciences and Technologies, Politecnico di Milano, Campus Bovisa, 20156, Milano, Italy
| | - Maurizio Quadrio
- Department of Aerospace Sciences and Technologies, Politecnico di Milano, Campus Bovisa, 20156, Milano, Italy.
| | - Jan O Pralits
- Department of Civil, Chemical and Environmental Engineering, University of Genova, Via Montallegro, 1, 16145, Genoa, Italy.
| |
Collapse
|
48
|
Han D, Zhang J, He G, Griffith BP, Wu ZJ. Computational fluid dynamics-based design and in vitro characterization of a novel pediatric pump-lung. Artif Organs 2024; 48:130-140. [PMID: 37860931 PMCID: PMC10841384 DOI: 10.1111/aor.14665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 09/22/2023] [Accepted: 10/05/2023] [Indexed: 10/21/2023]
Abstract
BACKGROUND Although extracorporeal membrane oxygenation (ECMO) has been used to provide temporary support for pediatric patients suffering severe respiratory or cardiac failure since 1970, ECMO systems specifically designed for pediatric patients, particularly for long-term use, remain an unmet clinical need. We sought to develop a new pediatric ECMO system, that is, pediatric pump-lung (PPL), consisting of a unique cylinder oxygenator with an outside-in radial flow path and a centrifugal pump. METHODS Computational fluid dynamics was used to analyze the blood fluid field for optimized biocompatible and gas exchange performances in terms of flow characteristics, hemolysis, and gas transfer efficiency. Ovine blood was used for in vitro hemolysis and gas transfer testing. RESULTS Both the computational and experimental data showed that the pressure drop through the PPL's oxygenator is significantly low, even at a flow rate of more than 3.5 L/min. The PPL showed better hemolysis performance than a commercial ECMO circuit consisting of the Quadrox-iD pediatric oxygenator and the Rotaflow pump at a 3.5 L/min flow rate and 250 mm Hg afterload pressure. The oxygen transfer rate of the PPL can reach over 200 mL/min at a flow rate of 3.5 L/min. CONCLUSIONS The PPL has the potential to provide adequate blood pumping and excellent respiratory support with minimal risk of hemolysis for a wide range of pediatric patients.
Collapse
Affiliation(s)
- Dong Han
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Jiafeng Zhang
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Ge He
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Bartley P. Griffith
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Zhongjun J. Wu
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Fischell Department of Bioengineering, A. James Clark School of Engineering, University of Maryland, College Park, Maryland, USA
| |
Collapse
|
49
|
Oliveira CL, Pace Z, Thomas JA, DeVincentis B, Sirasitthichoke C, Egan S, Lee J. CFD-based bioreactor model with proportional-integral-derivative controller functionality for dissolved oxygen and pH. Biotechnol Bioeng 2024; 121:655-669. [PMID: 38031493 DOI: 10.1002/bit.28598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 09/26/2023] [Accepted: 10/30/2023] [Indexed: 12/01/2023]
Abstract
A physics-based model for predicting cell culture fluid properties inside a stirred tank bioreactor with embedded PID controller logic is presented. The model evokes a time-accurate solution to the fluid velocity field and overall volumetric mass transfer coefficient, as well as the ongoing effects of interfacial mass transfer, species mixing, and aqueous chemical reactions. The modeled system also includes a direct coupling between process variables and system control variables via embedded controller logic. Satisfactory agreement is realized between the model prediction and measured bioreactor data in terms of the steady-state operating conditions and the response to setpoint changes. Simulation runtimes are suitable for industrial research and design timescales.
Collapse
Affiliation(s)
- Christopher L Oliveira
- Bristol Myers Squibb Company, Global Product Development and Supply, Devens, Massachusetts, USA
| | - Zoe Pace
- Bristol Myers Squibb Company, Global Product Development and Supply, Devens, Massachusetts, USA
- Biomedical Engineering Department, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | | | | | | | - Susan Egan
- Bristol Myers Squibb Company, Global Product Development and Supply, Devens, Massachusetts, USA
| | - Jongchan Lee
- Bristol Myers Squibb Company, Global Product Development and Supply, Devens, Massachusetts, USA
| |
Collapse
|
50
|
Marx R, Liu H, Yoon S, Xie D. CFD evaluation of hydrophobic feedstock bench-scale fermenters for efficient high agitation volumetric mass transfer. Biotechnol J 2024; 19:e2300384. [PMID: 38403465 DOI: 10.1002/biot.202300384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 12/08/2023] [Accepted: 01/02/2024] [Indexed: 02/27/2024]
Abstract
A new biomanufacturing platform combining intracellular metabolic engineering of the oleaginous yeast Yarrowia lipolytica and extracellular bioreaction engineering provides efficient bioconversion of plant oils/animal fats into high-value products. However, predicting the hydrodynamics and mass transfer parameters is difficult due to the high agitation and sparging required to create dispersed oil droplets in an aqueous medium for efficient yeast fermentation. In the current study, commercial computational fluid dynamic (CFD) solver Ansys CFX coupled with the MUSIG model first predicts two-phase system (oil/water and air/water) mixing dynamics and their particle size distributions. Then, a three-phase model (oil, air, and water) utilizing dispersed air bubbles and a polydispersed oil phase was implemented to explore fermenter mixing, gas dispersion efficiency, and volumetric mass transfer coefficient estimations (kL a). The study analyzed the effect of the impeller type, agitation speed, and power input on the tank's flow field and revealed that upward-pumping pitched blade impellers (PBI) in the top two positions (compared to Rushton-type) provided advantageous oil phase homogeneity and similar estimated kL a values with reduced power. These results show good agreement with the experimental mixing and kL a data.
Collapse
Affiliation(s)
- Richard Marx
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Huolong Liu
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Seongkyu Yoon
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| | - Dongming Xie
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts, USA
| |
Collapse
|