叶顶间隙对涡轮非定常气动性能的影响

为了分析动静干涉条件下叶顶泄漏流动对涡轮气动性能的影响,对某高负荷低压涡轮级进行了不同动叶叶顶间隙下的定常和非定常数流动的值模拟研究。结果表明:叶顶泄漏流动对上游静叶和动叶中、下部区域影响极小,影响范围主要体现在叶顶区域;随着叶顶间隙增加,动叶能量损失增加,且非定常条件下的损失增加比定常条件下大;叶顶泄漏流动对叶顶通道涡的发展和生成具有抑制效果;动静干涉效应对于泄漏涡的生成、发展、运行轨迹以及范围都有影响,且随着叶顶间隙的增加这种影响效果逐渐变得明显。

Effect of the Tip Clearance on Turbine Unsteady Aerodynamic Performance

For studying on the effects of the tip clearances flow on the turbine aerodynamic performance in the rotor-stator interaction condition, this paper used a high-loaded LP turbine to do the numerical simulation on the steady and unsteady flow in the different rotor tip clearances. The results shown that the tip leakage flow has little effect to the upstream stator and the middle, lower region of rotor, the range of influence is mainly reflected in the top area of the rotor; the energy loss of rotor increased with the increase of tip clearance, and the increase of loss in the unsteady condition is more than in the steady condition; the tip leakage flow has an inhibition effect on the generation and development of the passage vortex; the rotor-stator interaction effect affects the generation, development, trajectory and region of influence of the leakage vortex, and with the increase of the tip clearance, the effect will become more and more obvious.