Heat transfer and entropy generation analysis of water-Fe3O4/CNT hybrid magnetic nanofluid flow in a trapezoidal wavy enclosure containing porous media with the Galerkin finite element method

Al-Kouz, W; Abderrahmane, A; Shamshuddin, M; Younis, O; Mohammed, S; Beg, OA; Toghraie, D

Abstract

The present study addresses theoretically and computationally the performance of electrically
conducting water-Fe3O4/CNT hybrid nanofluid in three-dimensional natural convective heat transfer
and entropy generation within a wavy-walled trapezoidal enclosure. The enclosure has two layers - a
hybrid nanofluid layer and a porous medium layer. A transverse magnetic field is applied in the upward
direction. Newtonian flow is considered and the modified Navier-Stokes equations are employed with
Lorentz hydromagnetic body force, Darcian and Forchheimer drag force terms. The wavy side planes
are heated down while the top and vertical planes are thermally insulated. A rectangular heated fin is
placed in the lower plane and several different locations of the fin are considered. The transformed,
non-dimensional system of coupled non-linear partial differential equations with associated boundary
conditions is solved numerically with the Galerkin finite element method (FEM) in the COMSOL
Multiphysics software platform. The effects of Darcy number, Hartmann number, volume fraction,
undulation number of the wavy wall and Rayleigh number (thermal buoyancy parameter) on the
streamlines, isotherms and Bejan number contours are studied. Extensive visualization of the thermal
flow characteristics is included. With increasing Hartmann number and Rayleigh number, the average
Bejan number is reduced strongly whereas average Nusselt number is only depleted significantly at
very high Rayleigh number and high Hartmann number. With increasing undulation number, there is a
slight elevation in average Bejan number at intermediate Rayleigh numbers, whereas the average Nusselt number is substantially boosted, and the effect is maximized at very high Rayleigh number.
Increment in Darcy number (i. e. reduction in permeability of the porous medium layer) is observed to
considerably elevate average Nusselt number at high values of Rayleigh number, whereas the contrary
response is computed in average Bejan number. The simulations are relevant to hybrid magnetic
nanofluid fuel cells and electromagnetic nano-materials processing in cavities.

Citation

Al-Kouz, W., Abderrahmane, A., Shamshuddin, M., Younis, O., Mohammed, S., Beg, O., & Toghraie, D. (2021). Heat transfer and entropy generation analysis of water-Fe3O4/CNT hybrid magnetic nanofluid flow in a trapezoidal wavy enclosure containing porous media with the Galerkin finite element method. European Physical Journal Plus, 136(11), 1184. https://doi.org/10.1140/epjp/s13360-021-02192-3

• Journal Article Type: Article
• Acceptance Date: Nov 17, 2021
• Publication Date: Nov 27, 2021
• Deposit Date: Dec 1, 2021
• Publicly Available Date: Nov 27, 2022
• Journal: The European Physical Journal Plus
• Publisher: EDP Sciences
• Volume: 136
• Issue: 11
• Pages: 1184
• DOI: https://doi.org/10.1140/epjp/s13360-021-02192-3
• Publisher URL: https://doi.org/10.1140/epjp/s13360-021-02192-3
• Related Public URLs: https://www.springer.com/journal/13360/
• Additional Information: Access Information : This version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Nature’s AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: http://dx.doi.org/10.1140/epjp/s13360-021-02192-3