Now-Newtonian flow between concentric cylinders and the effects of finite compressibility

Abstract

Previous studies of the flow of a model soft-sphere liquid between rotating vertical concentric cylinders have predicted an enhanced depression of the free surface at the inner cylinder and the necessity and importance of accounting for finite compressibility. In those studies the rheological properties of the liquids were taken directly from computer simulations, whereas in the present work the liquid properties are altered in a controlled manner and the fluid dynamics problems is again solved numerically and self-consistently with the original boundary conditions. Specific alterations include the removal of all non-Newtonian properties, the change in sign of a generalized viscosity to create a rodclimbing or Weissenberg effect, and the removal of shear dilatancy or increase in pressure with shear. Our conclusion is that nonzero compressibility needs to be taken into account only in the presence of shear dilatancy. Show more