Transonic High Reynolds Number Transition Model Validation Based on ETW Cryogenic Wind Tunnel Data

Abstract

This article presents numerical results for the validation of the DLR $\gamma$ transition model based on cryogenic wind tunnel data obtained in the European Transonic Windtunnel. The extensive wind tunnel test campaign within the LuFo VI-2 project ULTIMATE provides validation data at high Reynolds numbers at transonic Mach numbers for a short/medium range aircraft configuration with a forward swept laminar wing. Experimental data includes global aerodynamic coefficients, local pressure measurements, transition location measurements based on temperature sensitive paint, and deformation data. This wide range of measurement data allows a thorough model validation. It is found that the DLR $\gamma$ transition model gives a precise transition prediction within the linear lift curve region where transition is found at the shock location. In addition, the effects of model deformation and turbulent wedges on the numerical results are investigated.