Effect of Rotation on Flow Field and Film Cooling Effectiveness in Film-Cooled Turbine Rotors

Abstract

AbstractExperimental and numerical investigations of flow field in a film-cooled turbine model under stationary and rotating conditions in a low-speed wind tunnel are conducted. The effects of different blowing ratios (M = 1.5, 2) on the flow field are studied. Results revealed a secondary flow near the blade surface in the wake region behind the jet hole. Compared with the stationary turbine, there exists centrifugal force and Coriolis force in the flow field of the rotating turbine, and these forces cause changes in the flow field in the rotating turbine. The effect of rotation on the flow field and film cooling effectiveness in the Y-Z planes on the pressure side is stronger than on the suction side, and results in lower film cooling effectiveness on the pressure surface of the rotating turbine blade compared with the stationary turbine. As the blowing ratio increases, the secondary flow in the wake region will become stronger, thereby enlarging the range of the wake.