%0 Journal Article
%T 跨声速涡轮叶顶间隙流动传热特性的数值研究<br>Numerical Investigations on Flow and Heat Transfer Characteristics of Transonic Turbine Blade Tips
%A 杜昆
%A 李军
%J 西安交通大学学报
%D 2016
%R 10.7652/xjtuxb201604022
%X 针对叶顶间隙的高速泄漏流及复杂的流动问题,采用求解三维Reynolds？？Averaged Navier？？Stokes(RANS)和S-A湍流模型的方法研究了跨声速流动条件下涡轮叶片顶部的流动传热特性,同时计算分析了叶顶间隙高度和进口湍流强度对顶部流动换热特性的影响。研究结果表明:叶顶间隙为0.188％动叶高度(小间隙)时,间隙泄漏流为亚声速(0.3<Ma<0.8)并具有最大的叶顶换热系数;当叶顶间隙高度增大至0.75％动叶高度时,间隙泄漏流出现超声速流动(1.0<Ma<1.3),叶顶平均换热系数最小;随着间隙高度增大,超声速流动区域从尾缘向前缘扩展,顶部换热系数先减小后增大。叶顶间隙高度的增大使得马蹄涡向吸力面侧移动,从而改变叶顶前缘附近换热系数分布;泄漏流在间隙区域急剧加速使得湍流水平显著降低,而进口湍流强度变化对于叶顶换热影响很小,但进口湍流强度增大时叶顶前缘吸力面侧二次流减弱。<br>The three？？dimensional steady Reynolds？？Averaged Navier？？Stokes (RANS) equation and the Spalart？？Allmaras turbulence model are used to investigate the high speed over？？tip leakage flow in a transonic turbine stage. Moreover, the influence of inlet turbulence intensity on heat transfer characteristics of top flows is investigated. The turbulence model is validated by a comparison with experimental data. Numerical results show that the blade tip attains the maximum heat transfer coefficient and the tip leakage flow is subsonic (0.3<Ma<0.8) when the tip clearance is small (s=0？？188％L). When the blade tip clearance increases to 0.75% of the moving blade height (L), the supersonic region enlarges towards the leading edge. The heat transfer coefficient on blade tip increases firstly, and then decreases as the tip clearance height increases. The minimum heat transfer coefficient on blade tip is obtained in the case s=0.75％L, and the leakage flow is supersonic (1.0<Ma<1.3) in the clearance gap. The heat transfer coefficient near the leading edge is significantly affected by the motion of the horse vortex with the increase of tip clearance height. Inlet turbulence intensity has little effect on the blade tip heat transfer performance due to the sharp acceleration of the leakage flow. However, it is observed that the cross？？passage secondary flow near the leading edge is weakened with high inlet turbulence intensity
%K 跨声速叶片
%K 叶顶间隙
%K 传热特性
%K 进口湍流度
%K 数值模拟&lt
%K br&gt
%K transonic blade
%K blade tip
%K heat transfer performance
%K inlet turbulence intensity
%U http://zkxb.xjtu.edu.cn/oa/DArticle.aspx?type=view&id=201604022