凹槽叶顶冷气射流对涡轮叶尖泄漏流动的影响

涡轮叶尖泄漏流动对涡轮通道内流动损失有着显著影响,叶顶冷气射流对控制叶尖泄漏流动和改善涡轮叶尖气热性能有重要意义。本文利用数值模拟方法,研究了叶顶冷气喷射位置和喷射流量对高压涡轮凹槽叶顶间隙泄漏流动控制的影响。文中重点分析了泄漏流动结构及涡轮气动效率的变化,探讨了冷气对刮削涡这一间隙内主控流动结构演化的影响。研究表明,冷气孔位置的变化对间隙内刮削涡的演化造成了一定影响,但并未造成涡轮整体效率的较大变化;而冷气喷射流量不仅影响到刮削涡结构演化,而且导致了涡轮级效率近0.5%的变化。

Effects of Cooling Jet in the Cavity on Tip-leakage Flow in the Turbine

The tip-leakage flow has significant effects on the flow loss of the turbine,and the blade tip cooling is of great significance to control the tip-leakage flow and improve the aerothermal performance of the blade tip.In this paper,the numerical simulation method is used to study the influence of the injection position and flow rate of the tip cooling on the control of the tip-leakage flow in the high pressure turbine.The change of tip-leakage flow structure and turbine stage efficiency is analyzed,and the influence of tip cooling on the evolution of the dominant flow structure in the gap of scraping vortex is discussed.The results show that the change of the positions of the cooling holes has a certain effect on the evolution of the scraping vortex in the gap,but it does not cause a great change in the overall efficiency of the turbine;and the cooling flow rate not only affects the evolution of the evolution of scraping vortex,but also causes the change of the turbine stage efficiency by nearly 0.5%.