采用大涡模型模拟了吹风比M=1.5时静止叶栅前缘射流孔为复合角度的流场结构,计算和分析了复合孔排叶片流场的三维流动结构及不同截面的涡量分布随时间的变化.结果表明:由于射流的存在,增加了流场的复杂性,流场中同时存在射流剪切层涡、马蹄形涡系、反向旋涡对和尾迹涡等4种涡系结构;叶片压力面和吸力面由于复合孔排的连续布置,冷却效果较好;射流的旋涡脱落呈周期性变化,第7排射流孔旋涡的脱落周期为0.04 s;在压力面侧,CVP的形成比吸力面早,涡的影响区域也相对较大.
Large eddy simulation(LES) was performed to investigate the flow structures of a stationary cascade's leading edge with a jet hole of compound angle under the blowing ratio of M=1.5.Three dimensional flowing structure of the blade with compound rows of film cooling holes and the vortices distribution on different sections varying with time were calculated and analyzed.Results show that the flow field becomes more complexity due to the jet existing,and four kinds of vortices,such as the jet shear-layer vortices,the system of horseshoe vortices,the counter-rotating vortex pair(CVP),the wake vortices,are existing in the flow field at the same time.The cooling effectiveness is better on the suction side and on the pressure side due to laying film-cooling holes with compound angles in series.The vortices shedding of the jet appears periodic variation,while the shedding period of the vortices for jet holes at row of No.7 is 0.04 s.The generation of CVP on the pressure side is earlier than that on the suction side and the effect zone of CVP on the pressure side is larger than that on the suction side.