Boundary Layer Transition Model With Compressibility Correction for Transonic Flow Simulations

The Medida-Baeder laminar-turbulent boundary layer transition model, based on Reynolds-averaged Navier-Stokes, has been extended by applying an existing compressibility correction. The correction was derived from the stability analysis of Tollmien-Schlichting instabilities and developed for the Langty-Menter transition model. Performance of the extended model was evaluated through the transonic flows over VA-2 and CAST10-2 airfoils where the compressible effects prevail. With the extended model, the prediction of transition onset is delayed, resulting in improved agreement with experimental data from the baseline model in skin friction distribution. Furthermore, the extended model was applied to the challenging NASA Common Research Model-Natural Laminar Flow wing-body configuration under transonic flight conditions. Sectional pressure coefficients and transition locations were compared with experimental results at various angles of attack. The prediction accuracy in transition onset along the wing span is improved, which are comparable with the predicting result from linear stability theory based transition model.