A Realizable Version of the k-w Turbulence Model

Abstract

This paper describes improvements in predictive quality to the original Wilcox k-ω turbulence model. A major disadvantage in the near-wall formulation of this model is usage of the large eddy inverse time-scale, ω ~ ε/k, even though small, dissipative eddies popular the immediate vicinity of walls. The present work suggests a correction to this problem through a realizable constraint introduced by the Kolmogorov time-scale. A second realizability constraint, the Schwarz condition, limits eddy viscosity magnitude in flow zones involving large normal strain gradients. Several examples demonstrate the improvements enabled due to these corrections, particularly in transonic and impinging flows where significant normal strain gradients occur. Keywords