进气畸变对压气机稳定性的影响

在低速大尺寸单级压气机实验器上,实验研究了动态进气畸变对压气机稳定边界的影响。并采取在静子叶片表面埋入微型压力传感器的方法,分析了压气机流场的动态压力特性。实验结果表明,动态总压畸变的旋转频率和旋转方向对压气机稳定性有很大的影响,当畸变相对转速n在0~+0．5之间时,压气机失速推迟;分析动态压力的频谱特性后知道,在压气机失速前一般存在与失速相关的压力扰动,动态总压畸变影响这种压力扰动,从而影响压气机的不稳定流动状态。

EFFECTS OF INLET DISTORTION ON STABILITY OF AN AXIAL COMPRESSOR

Experimental tests have been carried out to investigate the influence of inlet distortion on compressor stability margin in a low speed single stage research compressor. The pressure dynamic proceedings of three cross-section of the stator surface had been investigated to understand the flow structure in a compressor. Results show that the frequency and rotating direction of inlet distortion are most important factors affecting stability of axial compressor. As the relative rotating speed of non-uniform screen in term of rotor speed is at the range of 0~+0.5, the value of stall margin variation is positive. This is indicated that stall has been postponed and the stability of the compressor can be improved. After analysis of the dynamic flow characteristics of pre-stall and post-stall operations by means of the unsteady vane surface pressure with miniature pressure transducers mounted in the blade, it is known that as the dynamic flow in compressor flow field cooperates with the unsteady flow of inlet distortion, the eigen-disturbance is eliminated or suppressed, so compressor stalls at smaller flow coefficient than that of uniform inlet condition.