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对锥顶角（扇形角）γ分别为１５°和３０°的垂直扇形气膜冷却单孔射流下游的流场和传热进行了详细的实验研究，并与相同实验条件下圆孔射流的情形进行了比较。结果发现，扇形喷口下游的速度边界层等值线具有两种基本的分布形态，即使在高吹风比Ｍ＝２．０时，扇形孔的下游也没有明显大于主流速度的射流区域出现。吹风比Ｍ≥１．０时喷孔两侧边缘处沿流向形成了一对转向相反、强度较弱的纵向耦合涡。在相同的吹风比下，扇形喷孔出口面积的增大能够有效地降低耦合涡的强度和Ｖ、Ｗ速度分量，从而提高了气膜冷却效率，尤其是提高了喷孔两侧下游位置上的冷却效率。在喷孔中线下游位置上，当吹风比Ｍ＝０．３时，扇形角γ的变化对冷却效率几乎无影响，而当吹风比Ｍ≥１．０时，扇形喷孔较圆孔的冷却效率明显高得多。在喷孔中线两侧ｚ／Ｄ＝１．３的位置上，当扇形角相同时，吹风比低的射流冷却效率较高；当吹风比相同时，扇形角γ＝１５°和３０°的冷却效率非常接近。
The flow fields and heat transfer downstream of a vertical fan-shaped single film jet with a cone angle (sector angle) γ of 15 ° and 30 ° were respectively studied in detail. Compared with the case of circular jet with the same experimental conditions Compared. The results show that the velocity boundary layer contour downstream of the fan orifice has two basic distribution patterns. No jet zone is observed downstream of the fan orifice even at a high blowing ratio M = 2.0. When the blowing ratio M≥1.0, a pair of longitudinal coupling vortices with the opposite turn direction and weak strength are formed along the flow direction at both sides of the jet hole. Under the same blowing ratio, the increase of outlet area of the fan orifice can effectively reduce the strength of the coupled vortex and the velocity components of V and W, so as to improve the film cooling efficiency, and in particular, enhance the position of the nozzle downstream of both sides Cooling efficiency. When the blowing ratio M = 0.3, the change of the fan angle γ has almost no effect on the cooling efficiency at the position downstream of the center line of the injection hole. However, when the blowing ratio M≥1.0, the cooling efficiency of the fan-shaped hole is larger than that of the circular hole Obviously much higher. In the position of z / D = 1.3 on both sides of the center line of the injection hole, when the sector angle is the same, the cooling efficiency of the jet with a low blowing ratio is higher; when the blowing ratio is the same, the cooling with the sector angle γ = 15 ° and 30 ° The efficiency is very close.