Effects of rotation and varying gravity on the onset of convection in a porous medium layer: a numerical study

Purpose The purpose of this study is to examine the influence of rotation and varying gravitational strength on the onset of thermal convection in a porous medium layer numerically. The porous layer is acted to uniform rotation and inconsistent downward gravitational field which changing with depth from the layer. The authors presented three categories of gravitational strength deviancy, namely, linear, parabolic and exponential. Design/methodology/approach The higher-terms Galerkin weighted residual procedure is applied to get the eigenvalue of the problem. Findings The results illustrate that both rotation parameter and gravity variation parameter suspend the arrival of convection. The measurement of the convection cells decreases on enhancing the rotation parameter and gravity variation parameter. Originality/value It is also found that the scheme is more stable for category exponential, whereas it is more unstable for category parabolic.