Development of a New Transitional Flow Model Integrating the Wray-Agarwal Turbulence Model with an Intermittency Transport Equation

摘要

This paper integrates an intermittency transport equation у into the Wall-Distance-Free Wray-Agarwal (WA) one-equation turbulence model to create a two-equation WA-γ model for computing transitional flows. The model is validated by computing transitional flows past flat plates in zero and slowly varying pressure gradients for which experimental data and computations using other transition models are available. Computational results for benchmark ERCOFTAC flat plate transitional flow cases namely the T3A, T3B, and T3A-under zero pressure gradients as well as the T3C2-5 under slowly varying pressure gradients are obtained and compared with the experimental data and the computations from other transitional models. In addition, transitional flows past S809 airfoil at varying angles of attack, flow past the Aerospatiale-A airfoil, as well as flow past the NLR-7301 two-element airfoil are computed. For all transitional flow test cases considered, good agreement between the computations and the experimental data is obtained. The WA-γ is found to be accurate and very efficient in computing transitional flows.