Computation of Compression Ramp Flow with a Cross-Diffusion Modified k-e Model

摘要

SINCE the advent of the standard k-e model, it has been vciy widely accepted as a quite dependable turbulence model in engineering field. Numerous tests however, have revealed its shortcomings in predicting nonequilibrium flows, such as the shock-wave/turbulent boundary-layer interaction flow over a ramp. In contrast, the k-co model of Wilcox1 produces significantly belter skin friction distribution than the k-s model for such nonequilibrium flows. Wilcox2 attributed the better performance of the k-co model to a cross diffusion between k and e implicitly contained in the a equation; k and s which determine the turbulence length scale near the wall under a nonnegligible pressure gradient are strongly interdependent on each other.