The Density-Driven Nanofluid Convection in an Anisotropic Porous Medium Layer with Rotation and Variable Gravity Field: A Numerical Investigation

Abstract

In this study, a numerical examination of the significance of rotation and changeable gravitational field on the start of nanofluid convective movement in an anisotropic porous medium layer is shown. A model that accounts for the impact of Brownian diffusion and thermophoresis is used for nanofluid, while Darcy's law is taken for the porous medium. The porous layer is subjected to uniform rotation and changeable downward gravitational field which fluctuates with the height from the layer by linearly or parabolic. The higher-order Galerkin technique is applied to obtain the numerical solutions. The outcomes demonstrate that the rotation parameter T_D, the thermal anisotropy parameter<em>h </em>and the gravity variation parameter <em>λ</em> slow the beginning of convective motion, whereas the mechanical anisotropy parameter <em>ξ</em>, the nanoparticle Rayleigh-Darcy number R_np, the modified diffusivity ratio NA_nf and the modified nanofluid Lewis number Le_nf quick the start of convective motion. For instance, by rising the gravity variation parameterfrom zero to 1.4, the critical nanofluid thermal Rayleigh-Darcy number R_nf,c and the critical wave numberboost maximum around 133% and 7%, respectively for linear variation of the gravity field, while it were 47% and 2.8% for parabolic variation of the gravity field. It is also observed that the system is more unstable for the parabolic variation of the gravity field.