Abstract Provided are numerically predicted distributions of film cooling effectiveness for single cylinder film holes and for single 15° forward diffused film cooling holes, with compound angles ranging from 0° to 180°. Hole inclination angle, with respect to the test surface, is 35° for all arrangements considered, and blowing ratios of 0.60 and 1.25 are used. Also presented are local flow secondary flow vector distributions, local flow streamwise vorticity distributions, and local variations of flow film cooling effectiveness. Significantly different variations of local and spatially-averaged film cooling effectiveness are evident from these results, as the magnitude of compound angle is altered. Of particular importance are the reduced tendencies for lift-off of coolant concentrations when the forward diffused holes are employed. As a result, overall, the most optimal thermal protection, associated with higher magnitudes of surface adiabatic film cooling effectiveness, is given by forward diffused holes at the higher blowing ratio of 1.25.

中文翻译：

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基于复合角变化的绝热气膜冷却效果数值研究

摘要 给出了复角范围为0°～180°的单缸气膜孔和单个15°前向扩散气膜冷却孔气膜冷却效率的数值预测分布。对于所有考虑的布置，孔相对于测试表面的倾角为 35°，使用的吹气比为 0.60 和 1.25。还介绍了局部流二次流矢量分布、局部流流向涡度分布和流膜冷却效率的局部变化。从这些结果中可以明显看出局部和空间平均薄膜冷却效率的显着不同变化，因为复合角的大小发生了变化。特别重要的是当采用前向扩散孔时冷却剂浓度升高的趋势降低。因此，