Turbulence Modeling For Highly Separated Flows

D. Stephen Nichols, Kidambi Sreenivas, Steve L. Karman, and Brent Mitchell
UT SimCenter at Chattanooga, The University of Tennessee at Chattanooga, Chattanooga, Tennessee, 37403

The objective of this study is to investigate the Detached Eddy Simulation (DES) modifications to the hybrid kappa-epsilon, kappa-omega (kappa epsilon kappa omega) turbulence model and the Scale Adaptive Simulation (SAS) modifications to the one-equation kappa-epsilon (1kappa epsilon) turbulence model. Additionally, modifications to the damping functions to the baseline 1 kappa epsilon model are presented and validated for a variety of test cases. Further, the Stress-omega (S omega) Reynolds stress model is tested alongside the 1 kappa epsilon and kappa epsilon kappa omega models. A blended dissipation equation is implemented into the S omega model and validated for a variety of test cases. A surface-mounted cube is chosen as the primary test case to examine specifically the highly separated wake flow. Multiple grid levels are used to identify the grid requirements necessary for accurate computations with the kappa epsilon kappa omega DES and 1 kappa epsilon SAS models.