STABILITY OF FLOW BETWEEN ARBITRARILY. SPACED CONCENTRIC CYLINDRICAL SURFACES INCLUDING THE EFFECT OF A RADIAL TEMPERATURE GRADIENT

摘要

The stability of Couette flow and flow due to an azimuthal pressure gradient between arbitrarily spaced concentric cylindrical surfaces is in¬vestigated. The stability problems are solved by using the Galerkin method in conjunction with a simple set of polynomial expansion functions. Results are given for a wide range of spacings. For Couette flow, in the case that the cylinders rotate in the same direction, a simple formula for predicting the critical speed is derived. The effect of a radial temperature gradient on the the stability of Couette flow is also considered. It is found that positive and negative temperature gradients are destabilizing and stabilizing respec¬tively.