喷管偏转对航空发动机特性影响的试验

Experiment on influences of nozzle deflection on aeroengine characteristic

通过整机地面试验的方法,对喷管偏转后发动机不同工作状态下各参数的分析,获得了矢量偏转时发动机推力损失、偏转效率、发动机工作特性变化等数据.试验结果表明:在相同高压转速下,随着几何矢量角的增大,发动机的推力损失增大,偏转效率先增大后减小;在相同几何矢量角下,随着转速的增加,发动机推力损失经历由增大到减小的过程,矢量喷管的偏转效率增大,但偏转效率均小于1;节流状态时发动机转速差随着几何矢量角的增大而增大,中间状态时发动机转速差不受几何矢量角的影响;发动机节流状态时的矢量偏转使风扇工作线上移,风扇裕度减小,工程应用中需考虑扩稳措施.

Based on the engine overall performance ground test and parameter analysis in case of nozzle deflection under different working conditions, the effect of nozzle deflection on engine thrust loss, deflection efficiency and engine working characteristics were obtained. The experimental results showed that the engine thrust loss increased and deflection efficien- cy increased at first and then decreased with the increase of geometric vector angle when compressor speed remained unchanged. The engine thrust loss increased at first and then de- creased, and the deflection efficiency increased with the increase of rotor speed when geomet- ric vector angle remained unchanged, but the deflection efficiency was always less than 1. Engine speed difference increased with the increase of geometric vector angle when engine worked in throttle rating and speed difference almost kept constant with the increase of geo- metric vector angle when engine worked in middle rating. Fan co-operating line moved up- ward and fan surge margin decreased in case of nozzle deflection. So the method of expanding stability should be adopted for the engineering application of vectoring nozzles.