Effect of throughflow and variable gravity field on thermal convection in a porous layer

Abstract

The problem deals with the criterion for the onset of Rayleigh-Benard convection with a throughflow and variable gravity field in a porous layer. Both boundaries are considered to be insulating to temperature perturbations. Flow in the porous layer is governed by Darcy-Forchheimer equation. The resulting eigen value is solved using regular perturbation technique with wave number ' a ' as a perturbation parameter. The Prandtl number arising due to throughflow and variable gravity parameter plays a crucial role in determining the stability. It is found that to stabilize or destabilise the system depends on types of boundary conditions, direction of throughflow and variable gravity field are discussed in details. Keywords—Linear stability; Rayleigh-Benard convection; throughflow; variable gravity field.