Abstract: In order to assess the effects of stator-rotor cavity rim sealing flow on the performance of a turbine rotor, a detailed 3D unsteady numerical investigation is presented. Compared with no cavity model, the time-solved results show that the rotating ingress and egress structures change the incidence angle before the rotor blades and stretch the horseshoe vortex in the hub region, thereby resulting in large changes in turbine exit conditions. The existence of stator-rotor cavity with no sealing flow can ingest the vane wake fluid and has positive effects on turbine performance. The interaction of sealing flow and upstream vane weak gives rise to the entropy in the blade passages. The turbine efficiency decreases by 2.1% when the sealing mass flow rate is 1.37% of the mainstream mass flow rate. This proves that the effects of sealing flow on turbine rotor performance are very large and should be considered in turbine design. 

Key words: Rim sealing flow; Mainstream flow; Performance; Turbine; Unsteady CLC number

摘要： 为了研究涡轮转静盘腔的轮缘封严气体对涡轮转子性能的影响,对其进行了详细的三维非定常数值模拟。通过与无盘腔模型比较,非定常结果显示交替进行的主流燃气入侵和封严气体出流改变了转子叶片进口的气流角度,拉伸了端壁附近的马蹄涡,因此引起涡轮出口流动条件的较大变化。存在涡轮转静盘腔但没有冷气时,主流导叶尾迹的部分流体入侵盘腔,对涡轮转子性能有正面的影响。封严气体与上游导叶尾迹的相互作用引起转子通道内熵增,当冷气量占主流流量的1.37%时,涡轮效率降低2.1%。证实了轮缘封严气体对涡轮转子性能有很大的影响,在涡轮设计中必须给予考虑。 

关键词: 轮缘封严流；主流；性能；涡轮；非定常