Localization of Flow Separation and Transition Over a Pitching NACA0012 Airfoil at Transitional Reynolds Numbers Using Hot Films

Abstract

Separation and transition of flow over a pitching airfoil at transitional Reynolds Number are analyzed experimentally. The method is based on a windowed correlation between hotfilm sensor signals taken simultaneously or synchronized based on the airfoil pitch angle. A comparison with large eddy simulation (LES) simulation obtained in the same conditions is presented and discussed. Our results agree very well with the LES data for the separation location during the pitchup. For the pitchdown, the results show differences with the LES. However, when the LES data are analyzed with the same correlation technique, the results are in a better agreement.