MHD Natural Convection and Sensitivity Analysis of Ethylene Glycol Cu-Al2O3 Hybrid Nanofluids in a Chamber with Multiple Heaters: A Numerical Study of Lattice Boltzmann Method

Abstract

The present work investigates the magnetohydrodynamic (MHD) convective heat transport of hybrid nanofluids in a chamber with multiple heaters (such as hot microchips). The multiple-relaxation-time (MRT) lattice Boltzmann method (LBM) and graphics processing unit (GPU) computing are used here. The present study is important due to its relevance to real-world applications, the use of advanced simulation techniques, the consideration of hybrid nanofluids, the inclusion of magnetohydrodynamics, and the identification of critical parameters influencing heat transfer. Thermally homogeneous blocks are set at the bottom of a rectangular enclosure filled with ethylene glycol Cu-Al2O3 hybrid nanofluids with temperature-dependent viscosity. The cold temperature of the enclosure’s left and right walls and the bottom and top surfaces is kept at adiabatic conditions. The numerical outcomes for the various parameters Rayleigh number ($10^4\le \text{Ra}\le 10^6$), volume fraction ($0.00\le \varphi \le 0.04$), Hartmann number ($0\le \text{Ha}\le 60$), and viscosity variation parameter ($0\le {\epsilon }^{\ast }\le 5$) are presented in terms of streamlines, isotherms, and the peripheral local and average Nusselt numbers for the heated chips. The results demonstrated that inside the chamber, the Rayleigh number ($\text{Ra}$), the Hartmann number ($\text{Ha}$), and the volume fraction of nanoparticles ($\varphi$) have the highest impact on the heat transfer rate for hybrid nanofluid. For increased $\text{Ha}$ from 0 to 20, while $\varphi =0.0$ and $\text{Ra}=10^6$, average Nusselt number decreased with 13.65%. For the same case, if the volume fraction was increased to $\varphi =0.04$, then the average Nusselt number decreased 14%. Finally, a sensitivity analysis was done to analyze the system’s correctness and effectiveness to determine the significance of the specified parameters.