Effects of suction–injection–combination (SIC) on the onset of Rayleigh–Benard magnetoconvection in a micropolar fluid

Abstract

The effects of suction–injection–combination (SIC) and magnetic field on the linear stability analysis of Rayleigh–Benard convection in a horizontal layer of an Boussinesq micropolar fluid is studied using a Rayleigh–Ritz techinque. The eigenvalues are obtained for free–free, rigid–free and rigid–rigid velocity boundary combinations with isothermal and adiabatic temperature conditions on the spin-vanishing boundaries. The eigenvalues are also obtained for lower rigid isothermal and upper free adiabatic boundaries with vanishing spin. The influence of various micropolar fluid parameters on the onset of convection has been analysed. It is found that the effect of Prandtl number on the stability of the system is dependent on the SIC being pro-gravity or anti-gravity. A similar Pe-sensitivity is found in respect of the critical wave number. It is observed that the micropolar fluid layer heated from below is more stable compared to the classical fluid layer.