Analysis of heat convection through micropolar hybrid nanofluid in a square cavity with incongruent temperature at vertical thick side-walls.

Numerical investigation of free convection in a micropolar Ag-Al2O3/water hybrid nanofluid filled square cavity with thermal and radiative flux on vertical thick side-walls. The finite difference method is imposed on dimensionless governing partial differential equations (PDEs) and solved with the Gauss-Seidel method supported by successive over-relaxation (SOR) and successive under relaxation (SUR). The thermophysical quantities of the hybrid nanofluid are estimated using the recently published empirical relations that are based on numerous theoretical and experimental results. The effects of calibrated physical parameters, the vortex viscosity parameter (0.5≤K≤5.0), radiation parameter (0.001≤ R≤0.1), Rayleigh number (103≤Ra≤105), the volume concentration of hybrid nanoparticles (0.0≤φℎnf≤ 0.04), etc. and thermal conductivity ratio Rk on the isotherms, streamlines, isolines of microrotation, local Nusselt number are analyzed through graphs. The average Nusselt number is highest in a setup with vertical side-walls of an Aluminum material wall with constant temperature and Copper material wall subjected to heat flux and radiational heat transfer compared to other combination of iron and copper walls. On interchanging the setting of the copper wall at constant temperature and Aluminum wall subjected to heat flux and radiational heat transfer, a rise of 5.2411% in NuL_avg and 5.3835% in NuR_avg. while in case of interchanging the setting of the copper wall at constant temperature and iron wall subjected to heat flux and radiational heat transfer, a rise of 25.1939% in NuL_avg and 25.7847% in NuR_avg. The NuR_avg is enhanced by 14.003 % with an increase in Ra from 103 to 105, 0.142 % with a change in R from 0.1 to 0.001, and 20.681% with an increase in φhnf from 0 to 4%. [ABSTRACT FROM AUTHOR]