采用数值模拟的方法，基于稳态雷诺平均方程（URANS）耦合k-ω SST模型和滑移网格法分析了涡轮叶片旋转扫掠条件下带有非定常气膜出流的外环腔内阵列冲击传热特性。在外环冲击-气膜复合冷却结构中，冲击孔和气膜孔呈交错排列，冲击距与冲击孔直径之比为1.25，斯特劳哈尔数St=2.35、3.52（对应转速Ω=10 000、15 000 r/min），吹风比M=0.5、1及1.5。结果表明：叶片旋转扫掠效应引起的气膜孔出口压力波动会诱导冲击孔入口的瞬时质量流量发生变化，而时均质量流量几乎保持不变；吹风比在0.5~1.5之间变化时，靶面的瞬时和时均平均冲击换热特性随着吹风比的增大而增强；相同的吹风比时，叶片转速的提高对靶面瞬时和时均换热特性的影响非常微小。

The heat transfer characteristics of array impingement jet in the shroud cavity with unsteady film effusion flow under the condition of rotating and sweeping turbine blades are numerically studied using a coupled k-ω SST model and the sliding mesh method based on the unsteady Reynoldsaverage equation(URANS).In the composite impingementfilm cooling structure of shroud,the jet holes and film holes are staggered,and the ratio of the jettoplate spacing to the jet hole diameter is 1.25.The Strouhal numbers St are 2.35 and 3.52(corresponding rotation speeds Ω are 10 000 r/min and 15 000 r/min),and the blowing ratios M are 0.5,1 and 1.5.The results show that the instantaneous mass flow at the inlet of the impingement hole changes due to the pressure fluctuation at the outlet of the film cooling hole caused by the blade rotating and sweeping effect,while the timeaveraged mass flow remains almost unchanged;when the blowing ratio varies from 0.5 to 1.5,the instantaneous and timeaveraged impingement heat transfer characteristics of the target surface are enhanced with the increase of blowing ratio;at the same blowing ratio,the increase of the blade rotation speed has very little effect on the instantaneous and timeaveraged heat transfer characteristics of the target surface.

TK221

中央高校基础科研基金（3102020OQD702）；国家重大科技专项（2017-III-0010-0036）