涡轮叶片前缘阵列冲击冷却流动及传热特性数值研究

本文采用SST湍流模型模拟了类前缘通道内蒸汽射流阵列冲击冷却的流动与传热特性,分析了雷诺数(Re=10000~50000)、孔径比(d/H=0.5~0.9)和孔间距比(S/H=2~6)对流动及传热性能的影响规律,得到了相应的传热和摩擦关联式。结果表明:在不同雷诺数下,d/H从0.5到0.9变化时,通道压力损失系数降低了76%~79%,靶面平均努塞尔数降低了45%~49%;S/H从2增至6时,通道压力损失系数增加了1.64~1.92倍,靶面平均努塞尔数增加了54%~64%;增大d/H、减小S/H可有效提高类前缘通道蒸汽冲击冷却的综合热力系数。本文研究结果可为未来先进燃气轮机高温涡轮叶片蒸汽冷却结构的设计提供参考和借鉴。

Numerical Study on Flow and Heat Transfer Characteristics of Jet Array Impingement Cooling in Turbine Blade Leading Edge

In this study,the SST turbulence model is used to simulate the flow and heat transfer characteristics of steam jet array impingement cooling in the quasi leading edge channel.The influence of Reynolds number(Re=10000~50000).hole diameter-to-impingement spacing ratio(d/H=0.5~0.9)and hole spacing-to-impingement spacing ratio(S/H=2~6)on flow and heat transfer performance is analyzed and the corresponding heat transfer and friction correlations are obtained.The results show that the channel pressure loss coefficient decreases 76%~79%and the average Nusselt number decreases 45%~49%at diffcrcnt Reynolds number when d/H varies from 0.5 to 0.9.The channel pressure loss coefficient increases 1.64~1.92 times and the average Nusselt number increases 54%~64%at different Reynolds number when S/H increases from 2 to 6.Increasing d/H and decreasing S/H can effectively improve the comprehensive thermodynamic coefficient of steam jet impingement cooling in quasi leading edge channel.The results of this paper may provide a reference for the design of steam cooling structure of advanced gas turbine high temperature blades in the future.