Impact of inconsistent viscosity on the stability of a rotating layer of couple stress fluid

Abstract

The present model considers viscosity of a couple stress fluid to be dependent on temperature and pressure. The stability of the rotating horizontal layer is analyzed by utilizing the normal mode technique and energy technique. The critical threshold obtained by the two theories is found to be the same and no subcritical region is found for the considered values. The couple stress and rotation are seen to stabilize while the viscosity variation is found to destabilize the system. The critical Rayleigh number values are found to depend on the reference pressure and temperature chosen at the top surface in the current work, and thus the convection can be controlled by controlling the reference temperature and pressure.