Heat Transfer Enhancement Using Al2O3-MWCNT Hybrid-Nanofluid inside a Tube/Shell Heat Exchanger with Different Tube Shapes

The high demand for compact heat exchangers has led researchers to develop high-quality and energy-efficient heat exchangers at a lower cost than conventional ones. To address this requirement, the present study focuses on improvements to the tube/shell heat exchanger to maximize the efficiency either by altering the tube's geometrical shape and/or by adding nanoparticles in its heat transfer fluid. Water-based Al₂O₃-MWCNT hybrid nanofluid is utilized here as a heat transfer fluid. The fluid flows at a high temperature and constant velocity, and the tubes are maintained at a low temperature with various shapes of the tube. The involved transport equations are solved numerically by the finite-element-based computing tool. The results are presented using the streamlines, isotherms, entropy generation contours, and Nusselt number profiles for various nanoparticles volume fraction 0.01 ≤ φ ≤ 0.04 and Reynolds numbers 2400 ≤ Re ≤ 2700 for the different shaped tubes of the heat exchanger. The results indicate that the heat exchange rate is a growing function of the increasing nanoparticle concentration and velocity of the heat transfer fluid. The diamond-shaped tubes show a better geometric shape for obtaining the superior heat transfer of the heat exchanger. Heat transfer is further enhanced by using the hybrid nanofluid, and the enhancement goes up to 103.07% with a particle concentration of 2%. The corresponding entropy generation is also minimal with the diamond-shaped tubes. The outcome of the study is very significant in the industrial field and can solve many heat transfer problems.

Thermal and solute aspects among two viscosity models in synovial fluid inserting suspension of tri and hybrid nanomaterial using finite element procedure

Inclusion of nanoparticles boosts thermal performance and is essential for thermal transport. The current investigation has been made to conduct research on heat mass transport in synovial material with the mixing of hybrid and tri-hybrid comprising variable viscosity past over a heated surface having constant density and a steady environment. The conservation laws have been considered in the presence of Lorentz force, heat generation/absorption, modified heat and mass fluxes together with chemical reaction. The mathematical model is developed in Cartesian coordinate in the form of coupled partial differential equation (PDEs). The derived PDEs are simplified by a boundary layer approach (BLA) and reduced PDEs have been converted into ordinary differential equation (ODEs) using scaling group Similarity transformation. The converted ODEs are highly nonlinear and have been solved numerically by finite elements scheme (FES). The used scheme is effective for nonlinear problem and can be frequently utilized to tackle nonlinear problems arising in mathematical physics.

Thermophoretic Movement Transport of Reactive Casson Nanofluid on Riga Plate Surface with Nonlinear Thermal Radiation and Uneven Heat Sink/Source

The flow of magnetized Casson nanofluid past a Riga surface is examined in this study. The model scrutinizes the impacts of nonlinear radiative, uneven heat sink/source, thermophoretic movement and chemical reaction. Additionally, model is considered water based nanofluid with nanoparticles CuO (Copper Oxide) and MgO (Magnesium Oxide). The flow mechanics transport through Riga plate is developed using coupled system of higher order equations have been mutated into ordinary order from partial order utilizing established similarity transform. These nonlinear equations are calculated by the usage of through the Galerkin weighted residual method (GWRM) along with Simpson’s one-third rule and procured results are visualized graphically. Verifications of attained numerical outcomes through available literature for limiting case are also presented and found in excellent agreement. Further, the results of engineering physical parameters were also highlighted. More so, the analysis show that an increment in the Casson term causes rise in the temperature profile for CuO and MgO nanofluid and also dominant behavior is noted in case of CuO nanofluid comparing with MgO nanofluid. Furthermore, higher values of volume fraction parameter rises the both velocity profiles f′ (η), g′ (η) for both MgO and CuO nanofluid cases.

Influence of Bioconvection and Thermal Radiation on MHD Williamson Nano Casson Fluid Flow with the Swimming of Gyrotactic Microorganisms Due to Porous Stretching Sheet

An analysis is performed for electrical MHD flow of Williamson Nano Casson fluid with heat transfer. The fluid is positioned toward a porous stretching sheet along with mass flux. The impact of chemical diffusion and nonlinear thermal Radiation are further discussed. A highly nonlinear partial differential equations presenting the Williamson Nano Casson fluid flow over permeable extending plate is transformed to ordinary differential equations through appropriate similarity transformation and solved them with a shooting method-using package ND-Solve on Mathematica. The ascendency of arising physical interpretation of thermo-physical parameter on energy field, highly concentration field and density field are perceived. The valuations are achieved graphically for numerous protuberant terms like non Newtonian Williamson parameter, bio convection, Peclet number, mixed convection Hartman number, Casson parameter, thermophoresis diffusion, bio convection Rayeigh number, Brownian motion and mixed convection terms. These diverse terms are applied on dimensionless velocity function, concentration function, temperature function and density of the motile microorganism and analyzed numerically in detail. It is detected that through rising the value of bio-convection and Peclet number, the microorganism field diminishing. Graphical diagrams are illustrating the consistency of the latest outcomes.