1+1/2对转涡轮中激波结构的数值研究

UNSTEADY NUMERICAL SIMULATION OF SHOCK SYSTEMS IN VANELESS COUNTER-ROTATING TURBINE

本文对1+1／2对转涡轮中激波及激波／叶排干扰等进行了详细的数值模拟。分析发现,1+1／2对转涡轮高压动叶流道中压缩波系与常规涡轮流道中的压缩波系存在明显的不同。1+1／2对转涡轮高压动叶吸力面60％轴向弦长处产生了一组压缩波,它与内伸波相交。在常规涡轮中,这组压缩波将不会出现;内伸波在吸力面的反射波很强,不能忽略。在常规涡轮中,内伸波的反射波可以忽略。由于尾迹及低压动叶的作用,高压动叶外伸波的影响范围和强度呈现周期性的变化。

A detailed unsteady numerical simulation has been carried out to investigate the shock systems in the high pressure turbine rotor and unsteady shock-wake interaction between coupled blade rows in a 1 + 1/2 counter-rotating turbine (VCRT). It could be found that the system of compression waves in the VCRT HP rotor differs from that in conventional turbine: (1) a group of pressure waves (SSPW) creates from suction surface after about 60% axial chord in the VCRT HP rotor, those waves intersect with the inner-extending shock. But in conventional turbine, the SSPW will not create. (2) The inner-extending shock first impinges on the next HP rotor suction surface and its echo wave is strong enough and could not be neglected, then the echo wave interacts with the HP rotor wake. But in conventional turbine, the echo wave of the inner-extending shock is so weak and always ignores. (3) Strongly influenced by the HP rotor wake and the LP rotor, the HP rotor outer-extending shock changed periodically when moves from one LP rotor leading edge to the next.