STABILITY OF VISCOUS FLOW DRIVEN BY AN AZIMUTHAL PRESSURE GRADIENT BETWEEN TWO POROUS CONCENTRIC CYLINDERS WITH RADIAL FLOW AND A CONSTANT HEAT FLUX AT THE INNER CYLINDER

A linear analysis for the instability of viscous flow between two porous concentric circular cylinders driven by a constant azimuthal pressure gradient is studied, when a radial flow through the permeable walls of the cylinders is present. Also, a constant heat flux at the inner cylinder is applied. The linearized stability equations form an eigenvalue problem, which are solved by using Runge-Kutta-Fehlberg scheme combined with a shooting method, termed unit disturbance method. It is found that the constant heat flux parameter N, even for a radially weak outward flow has a strong stabilizing effect and the stabilization is more as the gap between the cylinders increases.