基于冷气射流的涡轮流动主动控制数值模拟

Numerical study on active flow control of turbine by using cooling jet

关键词:  变循环发动机  冷气射流  流量控制  涡轮性能  出口参数

Key words:  Variable cycle engine  Cooling jet  Flow control  Turbine performance  Exit coefficients

摘要:

针对变循环发动机在工作过程中进行涡轮流量调节的需求，以某涡轮的第一级作为研究对象，采用三维数值模拟的方式，对在导叶上不同射流位置、射流角度、射流流量的流场进行计算。结果表明：涡轮流量调节量对于射流位置十分敏感，在喉部上游附近的流量调节量最大；加入射流后涡轮损失增加，损失主要发生在射流于壁面上的流动区域；加入射流后，沿径向的大部分导叶出口气流角增大，从轮缘至轮毂导叶出口气流马赫数先增大后减小；涡轮流量调节效果与射流角度、射流流量成正比，当射流位于喉部附近、射流角度为90°、相对射流量为5%时，涡轮进口流量改变量达到13.03%，说明利用叶片表面射流，可以达到调节涡轮流量的目的。

Abstract:

In order to meet the requirements of variable cycle engine for turbine flow regulation in the working process， and taking the first stage of a turbine as the research object， and the flow field of different jet positions， jet angles and jet flow rates on the guide vane is studied by means of three-dimensional numerical simulation. The results indicate that the turbine adjustment flow rate is very sensitive to the jet position， and the maximum flow regulation area is near the upstream of the throat. The loss of turbine increases after adding jet， and the loss mainly occurs in the flow area of jet on the wall. After the jet is added， most of the outflow angles of guide vane along the radial direction increase， and the outflow Mach number of guide vane from the shroud to the hub increases first and then decreases. The turbine adjustment flow rate is proportional to the jet angle and the jet flow rate. When the jet is near the throat， the jet angle is 90°， and the relative jet flow rate is 5%， the inlet flow rate changes by 13.03%. which indicates that the purpose of adjusting the turbine flow rate can be achieved by using the jet from the vane surface.