可转导叶由于端部间隙和转轴的存在，会产生复杂的二次流动。本文对LISA涡轮进行变几何改型，采用几何约化法对该1.5级变几何涡轮进行数值模拟，详细探究了可转导叶间隙高度对可转导叶（S1）涡系的流动细节和载荷的影响，并深入研究其非定常流动对下游叶排的干涉及二次流输运过程的影响。计算结果表明：泄漏涡（LV）、角涡（CV）和通道涡（PV）共同组成了可转导叶的涡系；可转导叶端部间隙高度影响流动损失和级效率大小，设计间隙下该变几何涡轮S1时均总压损失系数Y为10.32%，涡轮时均总总效率ηtt为82.26%；可转导叶的尾缘泄漏涡使第1级动叶（R1）流动产生强非定常性；可转导叶的尾缘泄漏涡和R1泄漏涡、壁面涡是造成第2级静叶（S2）流动非定常性的主要因素。

The secondary flow in the adjustable vane is complicated due to the existence of end clearance and rotating shaft. In this paper, the variable geometry modification of LISA turbine was carried out, and the 1.5stage variable geometry turbine was simulated by Domain Scaling method. The influence of adjustable vane clearance height on flow details of S1 vortex system and load were explored. Else, the influence and secondary flow transport processes of unsteady flow on downstream blade row was deeply studied. The results show that: leakage vortex, corner vortex and passage vortex form the vortex system of adjustable vane. The tip clearance height of adjustable vane affects the loss and stage efficiency, the timeaverage total pressure loss coefficient of the variablegeometry turbine S1 is 10.32%, and the timeaverage total efficiency of the turbine is 82.26% under the design clearance. The trailing edge leakage vortex of S1 makes the R1 highly unsteady. The trailing edge leakage vortex of S1, R1 leakage vortex and wall vortex are the main causes of the flow instability of S2.

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国家自然科学基金（51979052）；黑龙江省自然科学基金优秀青年项目（YQ2020E024）；哈尔滨工程大学中央高校基本科研业务费专项基金（3072020CFT0304）；国家科技重大专项（J2019-II-0009-0029）