CONDITIONAL STABILITY FOR THERMAL CONVECTION IN A ROTATING COUPLE-STRESS FLUID SATURATING A POROUS MEDIUM

摘要

A conditional stability threshold for rotating couple-stress fluid heated from below and saturating a porous medium is exactly the same as the linear instability boundary. The optimal result is important because it shows that linear theory has completely captured the physics of the onset of convection. It is also found that couple-stress fluid saturating a porous medium is thermally more stable than ordinary viscous fluid. The effect of the couple-stress parameter, medium permeability, rotation, and Darcy number on the onset of convection is also analyzed.