The effect of wake parameters on the transitional boundary layer on turbine blade

This paper presents an experimental analysis of the interaction between wakes and boundary layers on an aerodynamic blade profile. The main objective of this research was to investigate the simultaneous influence of the freestream conditions and wake parameters on the wake-induced transition process. The investigations were performed for two levels of inlet freestream turbulence Tu = 0.4 and 3 per cent. The wakes were generated by cylindrical bars mounted in the rotating wheel. It was shown that wake parameters and especially the turbulence in the wake and wake width have a great influence on the position and extent of the induced transition. The role of freestream turbulence on the wake structure passing over the blade surface was also emphasized.