采用雷诺平均Navier-Stokes方程和Spalart-Allmaras湍流模型,对可控涡设计的1.5级高负荷亚音速试验涡轮进行三维黏性数值模拟,对叶栅内旋涡发展和损失机制进行全面研究和分析。数值研究表明,在高负荷涡轮动叶栅内,马蹄涡吸力面分支到达吸力面之后并没有消失,而是和压力面分支相交,并一起向下游发展,其位置始终处于压力面分支下侧,紧贴吸力面端部附近,并没有发生相互缠绕作用。受动叶栅通道内强横向压力梯度作用,端壁附面层从压力面侧直接被推向了吸力面侧,所形成的通道涡没有发生强烈的旋涡运动,位置始终限制在叶栅吸力面端壁附近的狭长区域内,呈片状涡结构。低能流体继续向吸力面角隅内运动和堆积,并向展向扩展,与主流发生强烈的掺混作用,损失急剧增加。因此,提高高负荷涡轮级效率的关键在于提高动叶性能。 Based on the Reynolds-averaged Navier-Stokes equation and the Spalart-Allmaras turbulence model, the 1.5-level high-load subsonic test turbine with controlled vortex design was subjected to 3-D viscous numerical simulation. The vortices development and loss mechanisms in cascade were thoroughly studied and analyzed. Numerical studies show that in the high-load turbine cascade, the branch of the horseshoe vortex suction surface does not disappear after reaching the suction surface, but intersects with the pressure surface branch and travels downstream. The position of the branch is always below the pressure surface branch, Close to the suction side near the end, and no mutual entanglement. Due to the strong lateral pressure gradient in the cascade passageway, the endwalls are directly pushed from the pressure surface to the suction surface, and the vortex formed by the vortex passage does not violently vortex. The position is always limited to the suction surface of the cascade Within the narrow area near the end wall, a sheet-like vortex structure. The low-energy fluid continues to move and accumulate in the corner of the suction surface and expand to the direction of expansion, strongly mixing with the mainstream and the loss increases rapidly. Therefore, the key to increasing the efficiency of a high-load turbine stage is to improve bucket performance.