Numerical simulation of secondary flows and longitudinal roll-cell structures in rotating channels

The rotation-modified k-epsilon model of turbulence is employed to simulate the effects of Coriolis forces on fully developed flow in rotating ducts of various cross-sections. The longitudinal roll-cell structures in flow through a parallel-plate channel subjected to a spanwise rotation are calculated and their influence on mean velocity distributions is considered. It is demonstrated that the secondary motion intensity in rectangular channels as well as in circular tubes can be successfully predicted with the wall-function approximation. Solutions with and without an additional counter-rotating pair of vortices are found for the flow in a channel of square cross-section. (Authors)