Comparative heat transfer analysis of electroconductive Fe3O4–MWCNT– water and Fe3O4–MWCNT– kerosene hybrid nanofluids in a square porous cavity using the non-Fourier heat flux model

Abstract

The analysis of heat transmission and fluid flow characteristics within the cavity is useful to improve the features of several applications including energy storage devices and hybrid fuel cells. With this motivation, the present model investigates the characteristics of magneto-convective heat transmission and fluid flow within a square porous enclosure with hot and cold slits. The heat transfer features of electrically conducting hybrid nanofluids Fe3O4–MWCNT– water and Fe3O4–MWCNT– kerosene are analyzed inside the enclosure. The non-Fourier thermal flux model is deployed, and the internal heat absorption/generation effect is considered. The marker-and-cell numerical scheme is adopted to solve the transformed dimensionless mathematical model with associated initial–boundary conditions. An exhaustive parametric investigation is implemented to estimate the influence of key parameters on transport phenomena. The computations show that augmenting the Hartmann number values modifies the fluid flow and temperature features substantially for both hybrid nanofluids. Enhancing the values of nanoparticles volume fraction promotes the heat transfer. When 5% Fe3O4–MWCNT nanoparticles are suspended into water and kerosene base fluids, Fe3O4–MWCNT– kerosene hybrid nanofluid achieves 6.85% higher mean heat transfer rate compared to Fe3O4–MWCNT– water hybrid nanoliquid. In the existence of heat absorption, the mean rate of heat transfer of Fe3O4–MWCNT– water hybrid nanofluid is 78.92% lower than Fe3O4–MWCNT– kerosene hybrid nanoliquid. Greater energy transmission is noticed in the case of Fe3O4–MWCNT– kerosene hybrid nanofluid, and the enhanced fluid flow is noticed in the case of Fe3O4–MWCNT– water hybrid nanofluid. Fourier's model (δe=0) estimates higher heat transfer rate than that of the Cattaneo–Christov (non-Fourier) heat flux model (δe≠0).