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尾迹涡是透平内部主要的非定常来源和重要的损失来源之一,精确模拟复杂分离湍流流动是当代CFD面临的一个挑战.本文先对透平尾迹涡研究进行了综述,然后采用高精度的DDES方法对VKI LS89进行了模拟,利用其精细的数值纹影图对尾迹涡的发展尤其是其尺度特性进行了分析并提出了物理解释.同时,对尾迹涡和激波、压力波的相互作用进行了分析.研究表明,叶片附近吸力面侧尾迹涡对主流的堵塞作用以及涡对中两个涡的相互作用对尾迹涡尺度特征起决定作用.激波和压力波对尾迹涡存在扰动和耗散,增加了尾迹涡的不稳定性.“,”The wake vortex is an important origin of unsteadiness and losses in turbines.However,the complex turbulent flow in turbines imposes a big challenge for modern computational fluid dynamics (CFD).This paper first reviews studies on the wake vortex,and then simulates the flow through a high pressure turbine vane-VKI LS89 with delayed detached eddy simulation (DDES) method.Physical analysis of the wake vortex development,especially the length characteristics,is carried out based on the detailed numerical Schlieren obtained from DDES results.At the meanwhile,the wake vortex-pressure waves interaction and wake vortex-shock wave interaction are also studied.The analysis finds out that the blockage effect of the downstream suction side wake vortex and the interaction between the vortex pair are responsible for the length characteristics.The shock wave and pressure waves enhance the instability of the wake vortex and dissipate the wake vortex.