中文摘要：

气膜冷却被广泛地应用在现代透平冷却设计中。由于叶栅环境的复杂性，叶栅气膜冷却特性与平板气膜冷却表现很不相同，主流流向压力梯度是叶栅流动的重要特征之一。本文采用PSP技术研究了不同流向压力梯度下的绝热气膜冷却效率，并同时进行了相应工况下的数值研究，来获得更详细的流场信息，以揭示流向压力梯度对气膜冷却有效度的影响机理。研究发现，低吹风比下，气膜冷却效率随流向顺压增大而提高，而高吹风比下，流向压力梯度对气膜冷却效率影响不大。

英文摘要：

Film cooling is widely used in modern turbine cooling system. Film cooling effectiveness is strongly influenced by turbine main flow and differs from flat plate condition. Streamwise pressure gradient is an important characteristic of turbine flow. The effects of streamwise pressure gradient on film cooling effectiveness are investigated using PSP technology. Numerical simulations are also conducted to gain more flow field information which can help analyze the physical mechanism of the effects of streamwise pressure gradient on film cooling effectiveness. Film cooling effectiveness is higher with greater favorable pressure gradient for low blowing ratios. While for high blowing ratios, cooling effectiveness doesn＇t vary much with stream wise pressure gradient.