1
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Li Z, Zhu D, Cao Y, Gao Z, Zhang C, Zhao F, Xue W. Rapid and ultra-sensitive trace metals detection of water by partial Leidenfrost superhydrophobic array surface enhanced laser-induced breakdown spectroscopy. Talanta 2024; 273:125832. [PMID: 38442562 DOI: 10.1016/j.talanta.2024.125832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 02/21/2024] [Accepted: 02/23/2024] [Indexed: 03/07/2024]
Abstract
The rapid and ultra-sensitive detection of trace elements in liquid is a primary concern for researchers. In this study, a partial Leidenfrost effect superhydrophobic (PLSHB) array surface was used for rapid in situ evaporation enrichment of sample droplets. Within 4 min, a 50 μL droplet sample was completely evaporated, resulting in all solutes in it being concentrated within a circular range measuring approximately 350 μm in diameter, without the formation of a coffee ring structure. The limits of detection for six metals (Pb, Ba, Be, Mn, Cr, Cu) in water were determined to be as follows: 0.82 μgL-1, 0.27 μgL-1, 0.033 μgL-1, 0.136 μgL-1, 0.241 μgL-1, and 0.083 μgL-1. Furthermore, laser-induced breakdown spectroscopy (LIBS) was employed to detect the enriched solutes from ten liquid samples with identical concentrations on the PLSHB array surface; these measurements exhibited a relative standard deviation (RSD) of only 3.7%. Spike experiments involving the addition of the aforementioned six metals into drinking water demonstrated recovery rates ranging from 85.7% to 117.7%. Therefore, the application potential of PLSHB array surface enhanced LIBS for rapid, stable, and ultra-sensitive detection and analysis of trace metal elements across various fields such as industry, environmental science, and biomedicine might be highly promising.
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Affiliation(s)
- Zhen Li
- China International Science & Technology Cooperation Base for Laser Processing Robotics, Zhejiang Provincial Key Laboratory of Laser Processing Robotics, College of Mechanical and Electrical Engineering, Wenzhou University, Wenzhou, 325035, China; Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, 325000, Zhejiang, China
| | - Dehua Zhu
- China International Science & Technology Cooperation Base for Laser Processing Robotics, Zhejiang Provincial Key Laboratory of Laser Processing Robotics, College of Mechanical and Electrical Engineering, Wenzhou University, Wenzhou, 325035, China
| | - Yu Cao
- Ruian Graduate College, Wenzhou University, Wenzhou, 325206, China
| | - Zhuode Gao
- China International Science & Technology Cooperation Base for Laser Processing Robotics, Zhejiang Provincial Key Laboratory of Laser Processing Robotics, College of Mechanical and Electrical Engineering, Wenzhou University, Wenzhou, 325035, China; Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, 325000, Zhejiang, China
| | - Chongyang Zhang
- China International Science & Technology Cooperation Base for Laser Processing Robotics, Zhejiang Provincial Key Laboratory of Laser Processing Robotics, College of Mechanical and Electrical Engineering, Wenzhou University, Wenzhou, 325035, China; Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, 325000, Zhejiang, China
| | - Fang Zhao
- China International Science & Technology Cooperation Base for Laser Processing Robotics, Zhejiang Provincial Key Laboratory of Laser Processing Robotics, College of Mechanical and Electrical Engineering, Wenzhou University, Wenzhou, 325035, China.
| | - Wei Xue
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, 325000, Zhejiang, China.
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2
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Yan X, Au SCY, Chan SC, Chan YL, Leung NC, Wu WY, Sin DT, Zhao G, Chung CHY, Mei M, Yang Y, Qiu H, Yao S. Unraveling the role of vaporization momentum in self-jumping dynamics of freezing supercooled droplets at reduced pressures. Nat Commun 2024; 15:1567. [PMID: 38378825 PMCID: PMC10879204 DOI: 10.1038/s41467-024-45928-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 02/06/2024] [Indexed: 02/22/2024] Open
Abstract
Supercooling of water complicates phase change dynamics, the understanding of which remains limited yet vital to energy-related and aerospace processes. Here, we investigate the freezing and jumping dynamics of supercooled water droplets on superhydrophobic surfaces, induced by a remarkable vaporization momentum, in a low-pressure environment. The vaporization momentum arises from the vaporization at droplet's free surface, progressed and intensified by recalescence, subsequently inducing droplet compression and finally self-jumping. By incorporating liquid-gas-solid phase changes involving vaporization, freezing recalescence, and liquid-solid interactions, we resolve the vaporization momentum and droplet dynamics, revealing a size-scaled jumping velocity and a nucleation-governed jumping direction. A droplet-size-defined regime map is established, distinguishing the vaporization-momentum-dominated self-jumping from evaporative drying and overpressure-initiated levitation, all induced by depressurization and vaporization. Our findings illuminate the role of supercooling and low-pressure mediated phase change in shaping fluid transport dynamics, with implications for passive anti-icing, advanced cooling, and climate physics.
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Affiliation(s)
- Xiao Yan
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China.
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing, 400030, China.
- Institute of Engineering Thermophysics, Chongqing University, Chongqing, 400030, China.
| | - Samuel C Y Au
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Sui Cheong Chan
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Ying Lung Chan
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Ngai Chun Leung
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Wa Yat Wu
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Dixon T Sin
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Guanlei Zhao
- State Key Laboratory of Automotive Safety and Energy, School of Vehicle and Mobility, Tsinghua University, Beijing, 100084, China
| | - Casper H Y Chung
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Mei Mei
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Yinchuang Yang
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Huihe Qiu
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Shuhuai Yao
- Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Hong Kong, China.
- HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute, Futian, Shenzhen, China.
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3
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Li A, Li H, Lyu S, Zhao Z, Xue L, Li Z, Li K, Li M, Sun C, Song Y. Tailoring vapor film beneath a Leidenfrost drop. Nat Commun 2023; 14:2646. [PMID: 37156802 PMCID: PMC10167315 DOI: 10.1038/s41467-023-38366-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 04/25/2023] [Indexed: 05/10/2023] Open
Abstract
For a drop on a very hot solid surface, a vapor film will form beneath the drop, which has been discovered by Leidenfrost in 1756. The vapor escaping from the Leidenfrost film causes uncontrollable flows, and actuates the drop to move around. Recently, although numerous strategies have been used to regulate the Leidenfrost vapor, the understanding of surface chemistry for modulating the phase-change vapor dynamics remains incomplete. Here, we report how to rectify vapor by "cutting" the Leidenfrost film using chemically heterogeneous surfaces. We demonstrate that the segmented film cut by a Z-shaped pattern can spin a drop, since the superhydrophilic region directly contacts the drop and vaporizes the water, while a vapor film is formed on the superhydrophobic surrounding to jet vapor and reduce heat transfer. Furthermore, we reveal the general principle between the pattern symmetry design and the drop dynamics. This finding provides new insights into the Leidenfrost dynamics modulation, and opens a promising avenue for vapor-driven miniature devices.
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Affiliation(s)
- An Li
- Key Laboratory of Green Printing, CAS Research/Education Center for Excellence in Molecular Sciences, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China
- University of Chinese Academy of Sciences, 100049, Beijing, P. R. China
| | - Huizeng Li
- Key Laboratory of Green Printing, CAS Research/Education Center for Excellence in Molecular Sciences, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China.
| | - Sijia Lyu
- Center for Combustion Energy, Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, 100084, Beijing, P. R. China
| | - Zhipeng Zhao
- Key Laboratory of Green Printing, CAS Research/Education Center for Excellence in Molecular Sciences, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China
- University of Chinese Academy of Sciences, 100049, Beijing, P. R. China
| | - Luanluan Xue
- Key Laboratory of Green Printing, CAS Research/Education Center for Excellence in Molecular Sciences, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China
- University of Chinese Academy of Sciences, 100049, Beijing, P. R. China
| | - Zheng Li
- Key Laboratory of Green Printing, CAS Research/Education Center for Excellence in Molecular Sciences, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China
| | - Kaixuan Li
- Key Laboratory of Green Printing, CAS Research/Education Center for Excellence in Molecular Sciences, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China
- University of Chinese Academy of Sciences, 100049, Beijing, P. R. China
| | - Mingzhu Li
- Key Laboratory of Green Printing, CAS Research/Education Center for Excellence in Molecular Sciences, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China
| | - Chao Sun
- Center for Combustion Energy, Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, 100084, Beijing, P. R. China.
- Department of Engineering Mechanics, School of Aerospace Engineering, Tsinghua University, 100084, Beijing, P. R. China.
| | - Yanlin Song
- Key Laboratory of Green Printing, CAS Research/Education Center for Excellence in Molecular Sciences, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, P. R. China.
- University of Chinese Academy of Sciences, 100049, Beijing, P. R. China.
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4
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van der Wijngaart H, Jagga S, Dekker H, de Goeij R, Piersma SR, Pham TV, Knol JC, Zonderhuis BM, Holland HJ, Jiménez CR, Verheul HMW, Vanapalli S, Labots M. Advancing wide implementation of precision oncology: A liquid nitrogen-free snap freezer preserves molecular profiles of biological samples. Cancer Med 2023; 12:10979-10989. [PMID: 36916528 DOI: 10.1002/cam4.5781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/18/2023] [Accepted: 02/24/2023] [Indexed: 03/16/2023] Open
Abstract
PURPOSE In precision oncology, tumor molecular profiles guide selection of therapy. Standardized snap freezing of tissue biospecimens is necessary to ensure reproducible, high-quality samples that preserve tumor biology for adequate molecular profiling. Quenching in liquid nitrogen (LN2 ) is the golden standard method, but LN2 has several limitations. We developed a LN2 -independent snap freezer with adjustable cold sink temperature. To benchmark this device against the golden standard, we compared molecular profiles of biospecimens. METHODS Cancer cell lines and core needle normal tissue biopsies from five patients' liver resection specimens were used to compare mass spectrometry (MS)-based global phosphoproteomic and RNA sequencing profiles and RNA integrity obtained by both freezing methods. RESULTS Unsupervised cluster analysis of phosphoproteomic and transcriptomic profiles of snap freezer versus LN2 -frozen K562 samples and liver biopsies showed no separation based on freezing method (with Pearson's r 0.96 (range 0.92-0.98) and >0.99 for K562 profiles, respectively), while samples with +2 h bench-time formed a separate cluster. RNA integrity was also similar for both snap freezing methods. Molecular profiles of liver biopsies were clearly identified per individual patient regardless of the applied freezing method. Two to 25 s freezing time variations did not induce profiling differences in HCT116 samples. CONCLUSION The novel snap freezer preserves high-quality biospecimen and allows identification of individual patients' molecular profiles, while overcoming important limitations of the use of LN2 . This snap freezer may provide a useful tool in clinical cancer research and practice, enabling a wider implementation of (multi-)omics analyses for precision oncology.
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Affiliation(s)
- Hanneke van der Wijngaart
- Department of Medical Oncology, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Sahil Jagga
- Applied Thermal Sciences, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Henk Dekker
- Department of Medical Oncology, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.,Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, The Netherlands
| | - Richard de Goeij
- Department of Medical Oncology, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.,Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, The Netherlands
| | - Sander R Piersma
- Department of Medical Oncology, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.,Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, The Netherlands
| | - Thang V Pham
- Department of Medical Oncology, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.,Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, The Netherlands
| | - Jaco C Knol
- Department of Medical Oncology, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.,Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, The Netherlands
| | - Babs M Zonderhuis
- Department of Surgery, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Harry J Holland
- Applied Thermal Sciences, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Connie R Jiménez
- Department of Medical Oncology, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.,Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, The Netherlands
| | - Henk M W Verheul
- Department of Medical Oncology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Srinivas Vanapalli
- Applied Thermal Sciences, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Mariette Labots
- Department of Medical Oncology, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.,Cancer Center Amsterdam, Imaging and Biomarkers, Amsterdam, The Netherlands
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5
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Gavrilyuk S, Gouin H. Theoretical model of the Leidenfrost temperature. Phys Rev E 2022; 106:055102. [PMID: 36559441 DOI: 10.1103/physreve.106.055102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 10/18/2022] [Indexed: 06/17/2023]
Abstract
The Leidenfrost effect is a phenomenon in which a liquid, poured onto a glowing surface significantly hotter than the liquid's boiling point, produces a layer of vapor that prevents the liquid from rapid evaporation. Rather than making physical contact, a drop of water levitates above the surface. The temperature above which the phenomenon occurs is called the Leidenfrost temperature. The reason for the existence of the Leidenfrost temperature, which is much higher than the boiling point of the liquid, is not fully understood and predicted. For water we prove that the Leidenfrost temperature corresponds to a bifurcation in the solutions of equations describing evaporation of a nonequilibrium liquid-vapor interface. For water, the theoretical values of obtained Leidenfrost temperature, and that of the liquid-vapor interface which is smaller than the boiling point of liquid, fit the experimental results found in the literature.
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Affiliation(s)
- Sergey Gavrilyuk
- Aix Marseille University, CNRS, IUSTI, UMR 7343, Marseille, France
| | - Henri Gouin
- Aix Marseille University, CNRS, IUSTI, UMR 7343, Marseille, France
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6
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Tenjimbayashi M, Manabe K. A review on control of droplet motion based on wettability modulation: principles, design strategies, recent progress, and applications. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2022; 23:473-497. [PMID: 36105915 PMCID: PMC9467603 DOI: 10.1080/14686996.2022.2116293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 08/09/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
The transport of liquid droplets plays an essential role in various applications. Modulating the wettability of the material surface is crucial in transporting droplets without external energy, adhesion loss, or intense controllability requirements. Although several studies have investigated droplet manipulation, its design principles have not been categorized considering the mechanical perspective. This review categorizes liquid droplet transport strategies based on wettability modulation into those involving (i) application of driving force to a droplet on non-sticking surfaces, (ii) formation of gradient surface chemistry/structure, and (iii) formation of anisotropic surface chemistry/structure. Accordingly, reported biological and artificial examples, cutting-edge applications, and future perspectives are summarized.
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Affiliation(s)
- Mizuki Tenjimbayashi
- International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, Japan
| | - Kengo Manabe
- Research Institute for Advanced Electronics and Photonics, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
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7
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Cai Z, Wang B, Liu S, Li H, Luo S, Dong Z, Wang Y. Enhancing Boiling Heat Transfer on a Superheated Surface by Surfactant-Laden Droplets. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:10375-10384. [PMID: 35980332 DOI: 10.1021/acs.langmuir.2c00745] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Boiling, one of the most common phase-change heat transfer methods, is widely used in nuclear power plants, spacecraft, integrated circuits, and other situations, where rapid and efficient heat transfer is crucial. However, boiling heat transfer is efficient only in a specific surface temperature range when a droplet impacts a superheated surface. Here, we enhance the boiling heat transfer and extend this temperature range by adding a tiny amount of surfactant. We find that surfactants can weaken the Kelvin effect of boiling bubbles, and thus reduce the onset of boiling driven temperature and significantly enhance the maximum vaporization rate of the droplet effectively. In particular, different from previous studies, we find that the surfactants at lower concentrations can increase the Leidenfrost temperature of the droplets. All the above effects jointly expand the temperature range of effective boiling heat transfer. This study sheds new light on the role of surfactants in the boiling process and offers a new medium to promote heat-transfer applications.
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Affiliation(s)
- Zhuojun Cai
- CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Bo Wang
- CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Shijie Liu
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Haofei Li
- CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Siqi Luo
- CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Zhichao Dong
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Yilin Wang
- CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
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8
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Saneie N, Kulkarni V, Fezzaa K, Patankar NA, Anand S. Boiling Transitions During Droplet Contact on Superheated Nano/Micro-Structured Surfaces. ACS APPLIED MATERIALS & INTERFACES 2022; 14:15774-15783. [PMID: 35343695 DOI: 10.1021/acsami.1c24009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Manipulating surface topography is one of the most promising strategies for increasing the efficiency of numerous industrial processes involving droplet contact with superheated surfaces. In such scenarios, the droplets may immediately boil upon contact, splash and boil, or could levitate on their own vapor in the Leidenfrost state. In this work, we report the outcomes of water droplets coming in gentle contact with designed nano/microtextured surfaces at a wide range of temperatures as observed using high-speed optical and X-ray imaging. We report a paradoxical increase in the Leidenfrost temperature (TLFP) as the texture spacing is reduced below a critical value (∼10 μm) that represents a minima in TLFP. Although droplets on such textured solids appear to boil upon contact, our studies suggest that their behavior is dominated by hydrodynamic instabilities implying that the increase in TLFP may not necessarily lead to enhanced heat transfer. On such surfaces, the droplets display a new regime characterized by splashing accompanied by a vapor jet penetrating through the droplets before they transition to the Leidenfrost state. We provide a comprehensive map of boiling behavior of droplets over a wide range of texture spacings that may have significant implications toward applications such as electronics cooling, spray cooling, nuclear reactor safety, and containment of fire calamities.
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Affiliation(s)
- Navid Saneie
- Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Varun Kulkarni
- Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Kamel Fezzaa
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 United States
| | - Neelesh A Patankar
- Mechanical Engineering, Northwestern University, Evanston, Illinois 60208 United States
| | - Sushant Anand
- Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, United States
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9
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Huang CT, Lo CW, Lu MC. Reducing Contact Time of Droplets Impacting Superheated Hydrophobic Surfaces. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2106704. [PMID: 35083861 DOI: 10.1002/smll.202106704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/23/2021] [Indexed: 06/14/2023]
Abstract
Reducing the contact time (tc ) of a droplet impacting a solid surface is crucial in various fields. Superhydrophobic (SHB) surfaces are used to reduce tc at room temperature. However, at high temperatures, SHB surfaces cannot achieve tc reduction because of the failure of the coating materials or the Leidenfrost (LF) effect. Therefore, a surface that can suppress the LF effect and reduce tc at high temperatures is required. To create such a surface, a double-reentrant groove (DRG) array surface with an overhanging structure on top of the microgrooves is developed. The overhanging structure renders the surface hydrophobic (HB). Despite its HB nature, the DRG surface's LF point (LFP) is observed at ≈530 °C, which is higher than the LFP on other HB surfaces. Moreover, a tc smaller than the inertia-capillary limit on the DRG surface is observed at between 400 and 500 °C. Accordingly, the DRG surface is currently the only HB surface for tc reduction at high temperatures. The DRG surface avoids the limitation of low LFPs observed on HB surfaces. Due to its HB properties, the DRG surface is determined to exhibit self-cleaning characteristics and can be used in various applications at high temperatures.
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Affiliation(s)
- Chung-Te Huang
- Department of Mechanical Engineering, National Taiwan University, Taipei, 10617, Taiwan
| | - Ching-Wen Lo
- Department of Mechanical Engineering, National Chung Hsing University, Taichung, 402, Taiwan
| | - Ming-Chang Lu
- Department of Mechanical Engineering, National Taiwan University, Taipei, 10617, Taiwan
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10
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Roy PK, Legchenkova I, Dombrovsky LA, Yu. Levashov V, Binks BP, Shvalb N, Shoval S, Valtsifer V, Bormashenko E. Thermophoretic levitation of solid particles at atmospheric pressure. ADV POWDER TECHNOL 2022. [DOI: 10.1016/j.apt.2022.103497] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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11
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Bobkova V, Trinschek S, Otte E, Denz C. Analyzing light-structuring features of droplet lenses on liquid-repelling surfaces. OPTICS EXPRESS 2022; 30:5937-5952. [PMID: 35209545 DOI: 10.1364/oe.444777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
The complete understanding of the formation of seemingly levitating droplets on liquid-repelling surfaces provides the basis for further development of applications requiring friction-free liquid transport. For the investigation of these droplets and, thereby, the underlying surface properties, standard techniques typically only reveal a fraction of droplet or surface information. Here, we propose to exploit the light-shaping features of liquid droplets when interpreted as thick biconvex elliptical lenses. This approach has the potential to decode a plethora of droplet information from a passing laser beam, by transforming the information into a structured light field. Here, we explore this potential by analyzing the three-dimensional intensity structures sculpted by the droplet lenses, revealing the transfer of the characteristics of the underlying liquid-repelling effect onto the light field. As illustrative complementary examples, we study droplet lenses formed on a non-wetting Taro (Colocasia esculenta) leaf surface and by the Leidenfrost effect on a heated plate. Our approach may reveal even typically "invisible" droplet properties as the refractive index or internal flow dynamics and, hence, will be of interest to augment conventional tools for droplet and surface investigation.
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12
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Ding W, Dorao CA, Fernandino M. Improving superamphiphobicity by mimicking tree-branch topography. J Colloid Interface Sci 2021; 611:118-128. [PMID: 34933190 DOI: 10.1016/j.jcis.2021.12.056] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 11/17/2022]
Abstract
when a droplet impacts on a superhydrophobic structured surface below a certain impact velocity, the droplet can bounce off completely from the surface. However, above such velocity a fraction of the droplet will pin on the surface. Surfaces capable of repelling water droplets are ubiquitous in nature or have been artificially fabricated. However, as the surface tension of the liquid is reduced, the capability of the surface to remain non-wetting gets hindered. Despite progress in previous research, the understanding and development of superamphiphobic surface to impacting low surface tension droplets remains elusive. It is proposed that multi-layer re-entrant like roughness can further enhance the anti-wetting properties also for low surface tension fluids. In this work, we produce patterned conical micro-structures with lateral nano-sized roughness. Furthermore, the droplet impact experiments are conducted on various surfaces with variable surface tensions (27 mN/m - 72 mN/m) by using droplets with different Weber numbers (2-170). We show that conical microstructures with lateral roughness mimicking tree-branches provides a surface topology capable of absorbing the force exerted by the droplet during the impact which prevents the droplet from pinning on the surface at higher impact velocity even for low surface tension droplets. Our study has significance for understanding the liquid interaction mechanism with the surface during the impact process and for the associated surface design considerations.
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Affiliation(s)
- Wenwu Ding
- Department of Energy and Process Engineering. Norwegian University of Science and Technology, Trondheim 7491, Norway
| | - Carlos Alberto Dorao
- Department of Energy and Process Engineering. Norwegian University of Science and Technology, Trondheim 7491, Norway
| | - Maria Fernandino
- Department of Energy and Process Engineering. Norwegian University of Science and Technology, Trondheim 7491, Norway.
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Chantelot P, Lohse D. Leidenfrost Effect as a Directed Percolation Phase Transition. PHYSICAL REVIEW LETTERS 2021; 127:124502. [PMID: 34597096 DOI: 10.1103/physrevlett.127.124502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 08/16/2021] [Indexed: 06/13/2023]
Abstract
Volatile drops deposited on a hot solid can levitate on a cushion of their own vapor, without contacting the surface. We propose to understand the onset of this so-called Leidenfrost effect through an analogy to nonequilibrium systems exhibiting a directed percolation phase transition. When performing impacts on superheated solids, we observe a regime of spatiotemporal intermittency in which localized wet patches coexist with dry regions on the substrate. We report a critical surface temperature, which marks the upper bound of a large range of temperatures in which levitation and contact coexist. In this range, with decreasing temperature, the equilibrium wet fraction increases continuously from zero to one. Also, the statistical properties of the spatiotemporally intermittent regime are in agreement with that of the directed percolation universality class. This analogy allows us to redefine the Leidenfrost temperature and shed light on the physical mechanisms governing the transition to the Leidenfrost state.
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Affiliation(s)
- Pierre Chantelot
- Physics of Fluids Group, Max Planck Center Twente for Complex Fluid Dynamics, MESA+ Institute, and J. M. Burgers Center for Fluid Dynamics, University of Twente, P.O. Box 217, 7500AE Enschede, Netherlands
| | - Detlef Lohse
- Physics of Fluids Group, Max Planck Center Twente for Complex Fluid Dynamics, MESA+ Institute, and J. M. Burgers Center for Fluid Dynamics, University of Twente, P.O. Box 217, 7500AE Enschede, Netherlands
- Max Planck Institute for Dynamics and Self-Organisation, Am Fassberg 17, 37077 Göttingen, Germany
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14
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Panchanathan D, Bourrianne P, Nicollier P, Chottratanapituk A, Varanasi KK, McKinley GH. Levitation of fizzy drops. SCIENCE ADVANCES 2021; 7:7/28/eabf0888. [PMID: 34233873 PMCID: PMC8262817 DOI: 10.1126/sciadv.abf0888] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 05/26/2021] [Indexed: 05/29/2023]
Abstract
As first described by Leidenfrost, liquid droplets levitate over their own vapor when placed on a sufficiently hot substrate. The Leidenfrost effect not only confers remarkable properties such as mechanical and thermal insulation, zero adhesion, and extreme mobility but also requires a high energetic thermal cost. We describe here a previously unexplored approach using active liquids able to sustain levitation in the absence of any external forcing at ambient temperature. We focus on the particular case of carbonated water placed on a superhydrophobic solid and demonstrate how millimetric fizzy drops self-generate a gas cushion that provides levitation on time scales on the order of a minute. Last, we generalize this new regime to different kinds of chemically reactive droplets able to jump from the Cassie-Baxter state to a levitating regime, paving the way to the levitation of nonvolatile liquids.
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Affiliation(s)
- Divya Panchanathan
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Philippe Bourrianne
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Philippe Nicollier
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Abhijatmedhi Chottratanapituk
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Kripa K Varanasi
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
| | - Gareth H McKinley
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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15
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McBride SA, Girard HL, Varanasi KK. Crystal critters: Self-ejection of crystals from heated, superhydrophobic surfaces. SCIENCE ADVANCES 2021; 7:7/18/eabe6960. [PMID: 33910891 PMCID: PMC8081363 DOI: 10.1126/sciadv.abe6960] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 03/09/2021] [Indexed: 05/31/2023]
Abstract
Mineral or crystal fouling (the accumulation of precipitants on a material and damage associated with the same) is a pervasive problem in water treatment, thermoelectric power production, and numerous industrial processes. Growing efforts have focused on materials engineering strategies (e.g., superhydrophobicity) to prevent fouling. Here, we present a curious phenomenon in which crystals self-eject from heated, nanotextured superhydrophobic materials during evaporation of saline water drops. These crystal structures (crystal critters) have exceedingly minimal contact with the substrate and thus pre-empt crystal fouling. This unusual phenomenon is caused by cooperative effects of crystallization, evaporative flows, and nanoscale effects. The temperature dependence of the critter effect can be predicted using principles of mass conservation, and we demonstrate that self-propulsion can be generated via temperature gradients, which promote asymmetric growth. The insights on confinement-driven evaporative crystallization can be applied for antifouling by self-ejection of mineral foulants, for drop-based fluidic machines, or even for self-propulsion.
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Affiliation(s)
- Samantha A McBride
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02141, USA
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, 08540 USA
| | - Henri-Louis Girard
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02141, USA
| | - Kripa K Varanasi
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02141, USA.
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16
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van Limbeek MAJ, Ramírez-Soto O, Prosperetti A, Lohse D. How ambient conditions affect the Leidenfrost temperature. SOFT MATTER 2021; 17:3207-3215. [PMID: 33623939 DOI: 10.1039/d0sm01570a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
By sufficiently heating a solid, a sessile drop can be prevented from contacting the surface by floating on its own vapour. While certain aspects of the dynamics of this so-called Leidenfrost effect are understood, it is still unclear why a minimum temperature (the Leidenfrost temperature TL) is required before the effect manifests itself, what properties affect this temperature, and what physical principles govern it. Here we investigate the dependence of the Leidenfrost temperature on the ambient conditions: first, by increasing (decreasing) the ambient pressure, we find an increase (decrease) in TL. We propose a rescaling of the temperature which allows us to collapse the curves for various organic liquids and water onto a single master curve, which yields a powerful tool to predict TL. Secondly, increasing the ambient temperature stabilizes meta-stable, levitating drops at increasingly lower temperatures below TL. This observation reveals the importance of thermal Marangoni flow in describing the Leidenfrost effect accurately. Our results shed new light on the mechanisms playing a role in the Leidenfrost effect and may help to eventually predict the Leidenfrost temperature and achieve complete understanding of the phenomenon, however, many questions still remain open.
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Affiliation(s)
- Michiel A J van Limbeek
- University of Twente, Physics of Fluids, Drienerlolaan 5, P. O. Box 217, 7500AE Enschede, The Netherlands.
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17
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Zhu Y, Yang F, Guo Z. Bioinspired surfaces with special micro-structures and wettability for drag reduction: which surface design will be a better choice? NANOSCALE 2021; 13:3463-3482. [PMID: 33566874 DOI: 10.1039/d0nr07664c] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Human beings learn from creatures in nature and imitate them to solve challenges in daily life. Thus, the use of bioinspired surfaces for drag reduction has attracted extensive attention in recent years due to their important applications in many fields, such as pipeline systems, maritime transportation, and military weapons. Herein, we introduce some typical plants and animals with low drag surfaces that exist in nature, focusing on their drag reduction patterns. There are two main mechanisms to explain how surfaces reduce frictional drag, where one is to design a suitable surface geometry to change the flow distribution of surrounding fluid and the other is to introduce a low friction lubricating layer (usually air or non-toxic silicone oil) to partially or completely replace the solid-liquid interface. Hence, by mimicking these organisms, some surfaces have been fabricated to reduce frictional drag, including riblets, superhydrophobic surfaces, and slippery liquid-infused porous surfaces. With the increasing research on drag-reducing surfaces, the drag reduction rate of different types of surface designs has greatly improved in recent years. This review provides a holistic overview that facilitates direct comparisons between these surface types. To select an optimal surface for drag reduction in practical applications, the merits and deficiencies of different surface designs are analysed and compared. Finally, based on the current challenges, we present some future prospects for the application of bioinspired surfaces in drag reduction.
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Affiliation(s)
- Yi Zhu
- Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, School of Materials Science & Engineering and Hubei Key Laboratory of Polymer Materials, Hubei University, Wuhan 430062, China.
| | - Fuchao Yang
- Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, School of Materials Science & Engineering and Hubei Key Laboratory of Polymer Materials, Hubei University, Wuhan 430062, China.
| | - Zhiguang Guo
- Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, School of Materials Science & Engineering and Hubei Key Laboratory of Polymer Materials, Hubei University, Wuhan 430062, China. and State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China
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18
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Wang S, Zhao X, Wu X, Zhang Q, Teng Y, Ahuja R, Zhang Y. Design of Continuous Transport of the Droplet by the Contact-Boiling Regime. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:553-560. [PMID: 33393313 DOI: 10.1021/acs.langmuir.0c03256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Joule-heat-driven directional transport of liquid droplets has comprehensive engineering applications in various water and thermal management, cooling systems, and self-cleaning. Generally, the driving force for the transport of liquid droplets was always observed at an extremely high Leidenfrost temperature, which limits the potential application between liquid boiling and Leidenfrost points. In this work, we design a new strategy to directionally drive the transport of droplets by blockading the vapor cushion at a temperature much lower than the Leidenfrost point. On the surface of the microhole arrays, we observed the continuous rebound behavior of ethanol droplets at Ts = 110 °C. Employing the thermal multiphase lattice Boltzmann model, the continuous rebound behavior was reproduced, verifying that the driving force was provided by the blockaded vapor pressure in microholes. By cooperating with the Laplace pressure difference, we directionally transport ethanol and water droplets on the horizontal asymmetrical concentric microridge surface. The horizontal velocity of water is 11.25 cm/s at Ts = 180 °C, similar to the traditional ratchets at the Leidenfrost point. The design of microtextures enriches the fundamental understanding of how to drive droplets at far below the Leidenfrost point and pushes the application in nongravity-driven self-cleaning and cooling systems.
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Affiliation(s)
- Shanlin Wang
- State Key Laboratory for Environment-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Xiaofeng Zhao
- State Key Laboratory for Environment-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, P. R. China
- Condensed Matter Theory Group, Materials Theory Division, Department of Physics and Astronomy, Uppsala University, 75120 Uppsala, Sweden
| | - Xian Wu
- State Key Laboratory for Environment-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Qingyu Zhang
- Shagang School of Iron and Steel, Soochow University, Suzhou 215137, P. R. China
| | - Yuancheng Teng
- State Key Laboratory for Environment-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Rajeev Ahuja
- Condensed Matter Theory Group, Materials Theory Division, Department of Physics and Astronomy, Uppsala University, 75120 Uppsala, Sweden
| | - Youfa Zhang
- Jiangsu Key Laboratory of Advanced Metallic Materials, School of Materials Science and Engineering, Southeast University, Nanjing 211189, P. R. China
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19
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Abstract
The gasification of multicomponent fuel drops is relevant in various energy-related technologies. An interesting phenomenon associated with this process is the self-induced explosion of the drop, producing a multitude of smaller secondary droplets, which promotes overall fuel atomization and, consequently, improves the combustion efficiency and reduces emissions of liquid-fueled engines. Here, we study a unique explosive gasification process of a tricomponent droplet consisting of water, ethanol, and oil ("ouzo"), by high-speed monitoring of the entire gasification event taking place in the well-controlled, levitated Leidenfrost state over a superheated plate. It is observed that the preferential evaporation of the most volatile component, ethanol, triggers nucleation of the oil microdroplets/nanodroplets in the remaining drop, which, consequently, becomes an opaque oil-in-water microemulsion. The tiny oil droplets subsequently coalesce into a large one, which, in turn, wraps around the remnant water. Because of the encapsulating oil layer, the droplet can no longer produce enough vapor for its levitation, and, thus, falls and contacts the superheated surface. The direct thermal contact leads to vapor bubble formation inside the drop and consequently drop explosion in the final stage.
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20
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M KR, Misra S, Mitra SK. Friction and Adhesion of Microparticle Suspensions on Repellent Surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:13689-13697. [PMID: 33156636 DOI: 10.1021/acs.langmuir.0c02651] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
With the recent advancements in the development and application of repellent surfaces, both in air and under liquid medium, accurate characterization of repellence behavior is critical in understanding the mechanism behind many observed phenomena and to exploit them for novel applications. Conventionally, the repellence behavior of a surface is characterized by the optical measurement of the dynamic contact angle of the target (to be repelled) liquid on the test surface. However, as already established in the literature, optical measurements are prone to appreciable error, especially for repellent surfaces with high contact angles. Here, we present an alternative, more accurate force-based characterization method of both friction and adhesion forces of microparticle-laden aqueous droplets over various repellent surfaces, where the force signature is captured by probing the surface with a droplet of the test liquid mounted at the tip of a flexible cantilever and then tracking the deflection of the tip of the cantilever as the probe droplet interacts with the surface. A systematic investigation of the response of repellent surfaces toward droplets with different microparticle concentrations reveals the dependency and sensitivity of measured adhesion and friction signature toward particle concentration. A comparison with the theoretical estimate from optical goniometry highlights the deviation of the theoretical data from experimentally measured values and further substantiates the need for such a force-based approach for accurate characterization of repellence behavior.
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Affiliation(s)
- Kiran Raj M
- Micro & Nano-Scale Transport Laboratory, Waterloo Institute for Nanotechnology, Department of Mechanical and Mechatronics Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Sirshendu Misra
- Micro & Nano-Scale Transport Laboratory, Waterloo Institute for Nanotechnology, Department of Mechanical and Mechatronics Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Sushanta K Mitra
- Micro & Nano-Scale Transport Laboratory, Waterloo Institute for Nanotechnology, Department of Mechanical and Mechatronics Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
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21
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Liu C, Sun K, Lu C, Su J, Han L, Wang Z, Liu Y. One-step process for dual-scale ratchets with enhanced mobility of Leidenfrost droplets. J Colloid Interface Sci 2020; 569:229-234. [PMID: 32113020 DOI: 10.1016/j.jcis.2020.02.076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 02/16/2020] [Accepted: 02/17/2020] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS Droplet depositing onto hot surfaces above the so-called Leidenfrost temperature will float on a cushion of its own vapor. The vapor flow below the drop could be rectified by asymmetric surface textures, resulting the self-propelled droplet motion. Asymmetric structures like ratchets are used to rectify Leidenfrost droplet movement. Hence, it is possible to enhance the droplet mobility using surfaces with combined asymmetric macro/micro-structures. EXPERIMENTS Continuous scale-like microcraters stacked end-to-end were fabricated on steel surfaces by wire electrical discharge machining (WEDM). The crater orientation always vectored towards the machining direction (MD), which oriented the droplet motion. Further, by integrating micro and macro-ratchets, dual-scale ratchets were constructed by one-step process using WEDM. The travelling velocities of Leidenfrost droplets on dual-scale and traditional single-scale ratchets were compared and the enhanced mechanism on dual-scale ratchets was analyzed. FINDINGS One-step process was developed to fabricate transport platforms for Leidenfrost droplets, that continuous scale-like microcraters formed simultaneously on the macroratchets. The highest droplet travelling velocity was achieved compared to previous research. Further study shows that the enhanced drop mobility is attributed to the dual-scale roughness which endows a larger propelling force. This finding presents a high-efficiency method to fabricate transport platforms for Leidenfrost droplets.
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Affiliation(s)
- Cong Liu
- Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Kuan Sun
- Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Chenguang Lu
- Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Junpeng Su
- Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Libao Han
- Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Zuankai Wang
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Yahua Liu
- Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China.
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