Details of Research Outputs

In order to predict the boundary layer transition automatically in viscous flow simulation, γ-Re transition model is implemented in a hybrid unstructured Reynolds averaged Navier-Stokes flow solver which was originally developed by the authors and named as HUNS3D. The transition model is built on two locally defined transport equations. The first equation is for intermittency and the second for the transition onset criterion based on momentum-thickness Reynolds number. The numerical algorithms for solving the transition model equations are the same as those for solving turbulence model equations. To validate and assess the ability and the accuracy of the HUNS3D's γ-Re transition model in predicting the boundary layer transition in typical aeronautical engineering cases, a series of free transitional flows around typical configurations, including flat plate, Aerospatial-A airfoil, NLR 7301 supercritical airfoil and NASA Trap wing high lift configuration, are simulated and the computed results are compared with corresponding experimental data, which demonstrate that the γ-Re transition model is very sensitive to the transition onset location and it predicts the natural transition and separation-induced transition accurately. With this transition model, the performance of the HUNS3D code in simulating the engineeringly realistic flow can be greatly enhanced.