AN ANALYSIS OF RNG-BASED TURBULENCE MODELS FOR HOMOGENEOUS SHEAR-FLOW

In a recent paper [Phys. Fluids A 2, 1678 (1990)], the authors compared the performance of a variety of turbulence models including the K-epsilon model and the second-order closure model derived by Yakhot and Orszag based on renormalization group (RNG) methods. The performance of these RNG models in homogeneous turbulent shear flow was found to be quite poor, apparently due to the value of the constant C-epsilon-1 in the modeled dissipation rate equation, which was substantially lower than its traditional value. However, recently a correction has been made in the RNG-based calculation of C-epsilon-1. It is shown herein that, with the new value of C-epsilon-1, the performance of the RNG K-epsilon model is substantially improved. On the other hand, while the predictions of the revised RNG second-order closure model are better, some lingering problems still remain that can be remedied by the addition of higher-order terms.