The performance of a full coverage film cooling configuration called cross-row (CR) configuration including upstream inlet leakage flow was studied by measuring the adiabatic film cooling effectiveness distribution using PSP technique. Experiments were conducted in a blow-down wind tunnel cascade facility at the isentropic exit Mach number of 0.5 corresponding to inlet Reynolds number of 3.8 x 105, based on axial chord length. A free-stream turbulence level was generated as high as 19% with a length scale of 1.7 cm at the inlet. The results are presented as two-dimensional adiabatic film cooling effectiveness distributions on the endwall surface with corresponding spanwise averaged distributions. The focus of this study is to investigate the effect of coolant-to-mainstream mass flow ratio (MFR) and density ratio (DR) on the proposed endwall cooling design. Initially, increased MFR for the endwall cooling and upstream leakage levels up the local adiabatic cooling effectiveness and yields relatively uniform coverage on the entire endwall. However, in either case, highest MFR does not provide any improvement as endwall cooling suffered from the jet lift-off and leakage coolant coverage restricted by the downstream near-wall flow field. Results also indicated a density ratio of 1.5 provides the best performance. Finally, a fair comparison is made with another design called axial-row (AR) configuration from a companion paper.
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机译：通过使用PSP技术测量绝热膜的冷却效率分布，研究了包括上游入口泄漏流在内的称为横行（CR）的全覆盖膜冷却结构的性能。实验是在排污风洞叶栅装置中进行的，等熵出口的马赫数为0.5，对应于轴向弦长，雷诺数为3.8 x 105。在入口处产生的自由流湍流度高达19％，长度比例为1.7 cm。结果表示为端壁表面上的二维绝热膜冷却效率分布，以及相应的翼展方向平均分布。这项研究的重点是研究冷却剂与主流质量流量比（MFR）和密度比（DR）对建议的端壁冷却设计的影响。最初，增加的端壁冷却MFR和上游泄漏水平提高了局部绝热冷却效率，并在整个端壁上产生了相对均匀的覆盖率。但是，在任何一种情况下，最高的MFR都不会提供任何改善，因为端壁冷却会受到射流升起和泄漏冷却液覆盖范围的限制，而下游冷却壁流场限制了冷却剂的覆盖范围。结果还表明，密度比为1.5时可提供最佳性能。最后，与随附论文中的另一种称为轴向行（AR）配置的设计进行了合理的比较。
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