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对前缘上游有单排和双排孔冷却的涡轮导向叶栅端壁进行了详细的传热实验 ,在吹风比 1 ,2 ,3下获得了当地气膜冷却效率和换热系数 ,结合流场测量结果分析了端壁冷却和换热规律。结果表明端壁气膜冷却在很大程度上受二次流的影响 ,冷却效果主要由吹风比决定 ,低吹风比喷射时 ,压力面附近的一个三角形区域没有冷气的覆盖 ,中、高吹风比喷射可以大幅度提高平均冷却效率并使冷气很均匀的覆盖在端壁上 ,双排孔喷射比单排孔喷射平均效率提高 1倍左右。结果还表明尽管冷气喷射使端壁换热系数随吹风比的增大而显著增大 ,气膜冷却还是能有效的降低端壁的热负荷 ,其中以中吹风比双排孔喷射的效果最为显著。
A detailed heat transfer experiment was carried out on the endwalls of turbine guide vanes with single row and double row holes cooling upstream of the leading edge. The local film cooling efficiency and heat transfer coefficient were obtained at blow ratio 1, 2 and 3, Field measurement results analyze the end wall cooling and heat transfer rules. The results show that the endwall film cooling is greatly affected by the secondary flow. The cooling effect is mainly determined by the blowing ratio. When the low blowing ratio is injected, a triangular area near the pressure surface has no cooling air coverage. The middle and high blowing ratio Spray can greatly improve the average cooling efficiency and make the air-conditioning cover the end wall is very uniform, double-row hole jet injection than the single-hole average efficiency increased by about 1 times. The results also show that despite the air-conditioning spray end wall heat transfer coefficient increases with the blowing ratio increased significantly, the film cooling can effectively reduce the thermal load on the end wall, which was blowing in the hair than the double-row spray effect is most significant .