基于压力敏感漆技术的尾迹对涡轮动叶前缘气膜冷却影响研究

The effects of unsteady wake on the leading edge film cooling effectiveness of the turbine blade were studied using the Pressure Sensitive Paint (PSP) measurement technique. The test blade has three rows of compound angled cylindrical film holes on the leading edge. The blowing ratio is varied from 1.0 to 3.0 and the wake Strouhal number is varied from 0 to 0.36. Results show that for the wake cases, an increase in the blowing ratio causes an increase in film cooling effectiveness over most of the blade surface except the pressure side next to the film holes. As the wake Strouhal number increases, the span-wise averaged film cooling effectiveness of the pressure side increases by up to 0.07, the span-wise averaged film cooling effectiveness of the leading edge decreases by up to 0.13 and that of the suction side decreases by up to 0.18. Overall, the wake causes a decrease in the film cooling effectiveness on most region of the leading edge on the turbine blade.