基于PLIF诊断技术的气膜冷却研究

Study on Film Cooling Based on PLIF Technology

摘要: 本文使用丙酮平面激光诱导荧光技术(Acetone-PLIF)，在掺混特性试验台上对冷却气膜与主气流的掺混进行了可视化测试。试验中采用的射流孔与实际叶片气膜孔处于同一尺度范围内。为研究气膜覆盖的完整性和贴壁性，定义了气膜的横截面长度和弯折角，并在三种吹风比下拍摄了掺混过程的荧光图像。通过图像处理，对上述参数进行了测量和分析，结论表明吹风比对气膜的有效覆盖长度和弯折角存在显著影响，在射流速度与主流相近时，气膜覆盖效果较好。通过图像，还捕捉到了射流孔附近的流动细节及变化规律。该技术在流体机械研究领域有广泛的应用前景。

Abstract: The film cooling visualization test is conducted on a mixed characteristic test bed using acetone PLIF method. The size of the jet hole in this experiment is in the same scale with the real one. In order to study the integrity and adherence of cooling film, the length and turning angle were de-fined and measured under 3 different conditions. The results showed that the blow rate has a sig-nificant influence on them. When the velocity of the jet and mainstream was close, the integrity of cooling film would be the best. The results also showed a lot of flow and mixing characteristics of film cooling. This technology has a bright future in study on fluid machinery.