气膜冷却是一种航空发动机中广泛应用的热防护技术，其中凹槽孔结构已被证明具有良好的冷却性能。本文提出了一种基于控制点的凹槽型线设计方法，并将其应用于凹槽下游几何型线的优化；发展了一种绝对余弦曲率调制的凹槽设计方法，以系统研究凹槽前缘曲率对冷却性能的影响。共评估了21种不同的凹槽构型，凹槽孔布置在平板模型上，凹槽内为流向倾角为30°的圆柱孔。采用压敏漆实验测量了绝热气膜冷却效率，并结合数值模拟分析了相应的流场特性。结果表明，基于控制点的设计方法具有更高的几何灵活性，并能获得最高的冷却效率。优化后的凹槽特征为前缘凸出且两侧相对平缓，优化后的凹槽构型促进了凹槽内冷气的横向扩散，改变了角涡的生成与输运过程，有效削弱了肾形涡对，并使冷气更贴近壁面且横向覆盖更宽。与基准直槽相比，优化设计的冷却效率最高提升了42.4%。敏感性分析进一步揭示，圆柱孔出口宽度范围内的凹槽型线对冷却效率影响最大，与圆柱孔射流相对应的最佳凹槽前缘曲率半径约为孔径的0.70倍。

Film cooling is a widely applied thermal protection technique in aero-engines, and trenched hole configurations have been demonstrated to provide superior cooling performance. In this study, a control-point-based trench profile design methodology is proposed and applied to optimize the downstream trench geometry. In addition, an absolute-cosine curvature-modulated trench configuration is developed to systematically investigate the influence of the trench leading-edge curvature on cooling performance. A total of 21 trench configurations are evaluated. The trenched holes are arranged on a flat-plate model with cylindrical injection holes of 30° inclination embedded within the trench. Adiabatic cooling effectiveness is measured using Pressure-Sensitive Paint experiments, and the associated flow field characteristics are examined through numerical simulations. The results demonstrate that the control-point-based design approach offers greater geometric flexibility and yields the highest cooling effectiveness. The optimized configuration is characterized by a protruding leading edge and relatively gentle sidewalls. The optimized configuration promotes the lateral spreading of coolant within the trench, alters the generation and transport of corner vortices, effectively weakens the counter-rotating vortex pair, and enables the coolant to remain closer to the wall while achieving a wider lateral coverage. Compared with the baseline straight trench, the optimized design achieves a maximum improvement in cooling effectiveness of up to 42.4%. Sensitivity analysis further reveals that the trench profile within the outlet width region of the cylindrical hole exerts the strongest influence on cooling effectiveness, and that the optimal leading-edge curvature radius associated with the cylindrical jet is approximately 0.70 times the hole diameter.