Effect of spanwise rotation on centrifugal instability in rotating curved non-isothermal flows

Abstract

The effect of spanwise rotation on the centrifugal instability is examined numerically in terms of flow structure transitions by a finite volume method. The specific problem considered is a steady, hydrodynamically and thermally fully developed flow in a square duct with a strong streamwise curvature, a spanwise rotation in both positive and negative directions and wall cooling. The rotation is found to be of considerable effect on flow structures. As well the effect is more complex for non-isothermal flows due to a buoyancy force which increases with the square of the rotation speed. Several hitherto unknown flow structures are revealed. The results cover both transitions in flow structures and effects of the flow transitions on temperature distributions.