变马赫数涡轮平面叶栅流场的实验研究

Experimental Investigation of Flow-Field in Turbine Cascade With Different Exit Mach Number

本文研究分析了三套涡轮平面叶栅设计攻角下变出口等熵马赫数时的气动性能,给出了三套涡轮叶栅设计攻角下的临界马赫数;阐述了叶栅出口总压恢复系数、能量损失系数、负荷系数及进口马赫数随出口等熵马赫数的变化规律;分析了叶片表面和叶栅端壁静压系数及等熵马赫数的分布情况。结果表明,三套叶栅所采用的叶型具有后部加载特性,具有较好的气动性能;叶栅出口能量损失系数随出口等熵马赫数的变化呈现出先减小后增大的变化规律。

The performance of turbine linear cascades with different exit mach number was studied experimentally in this paper,critical mach number was given,the variation laws of total pressure recovery coefficient and energy loss,load factor and isentropic inlet mach number with isentropic exit mach number were discussed;the distribution of aerodynamic parameters on the blade surface and end wall,was analyzed.The results show that the blade profile of the cascades has obvious characteristic of the aft-loading.The energy loss coefficients at the exit of cascade in the entire range of incidences are low and it is found that the energy loss coefficients decreases firstly and increases at last with the change of the isentropic exit Mach number.