涡轮工作叶片型面气膜孔流量系数的实验研究

Discharge Coefficient Measurements of Film Cooling Holes on Blade Surface in a Turbine Cascade

对涡轮工作叶片表面不同位置气膜孔的流量系数进行了系统的测量,在不同吹风比和雷诺数下测得了流量系数值,并分析了各种因素对流量系数的影响程度。结果表明在不同位置气膜孔流量系数分布规律有较大区别,孔排位置一定时,流量系数主要由吹风比决定。该实验结果对涡轮工作叶片表面气膜冷却的设计研究有重要意义。

Discharge coefficients of film cooling holes on the turbine blade surface were measured in a largescale low speed turbine cascade.Discharge coefficients of coolant injection were obtained in the region of Re∞=250,000～450,000,and BR=05～25.The influences of Reynolds numbers and blowing ratios on discharge coefficients were investigated.The results show that turbine blade surface film hole discharge coefficients are different greatly for different hole array positions.The distribution of discharge coefficients is mainly determined by blowing ratio for the same geometry.Film hole discharge coefficients were increased obviously with blowing ratio in the case of low blowing ratio.In the case of high blowing ratio,the discharge coefficients became a constant.