Numerical Investigation Based on Kriging Surrogate Model of Tip Leakage Flow Controlled by DBD Plasma

In this paper, the influence of multiple plasma actuators arranged on the tip of the turbine blade on the tip leakage flow is studied by numerical method. The results show that the number of actuators and the combination of their positions have a significant impact on the tip leakage flow. The optimum position for arranging the plasma actuator along the suction side is about 55% S/S_ps, and the control effect near the trailing edge is much better than near the leading edge when the number of actuators are the same. A vortex is induced by actuators on the blade tip near the suction side, hindering the fluid flow in the tip gap and reducing the velocity of leaking flow. At the same time, the separation of the separation bubble is advanced, which is beneficial to reduce the mixing loss. The controlling effect on the leakage flow does not continue to increase with the increase of the number of plasma actuators. When the actuators are arranged optimally, the controlling effect reaches its limit, in which case the leakage massflow is reduced by 46% compared with the baseline case, and the corresponding energy loss of the exit section is reduced by 15.7%.