低速离心压缩机旋转失速的试验研究

Rotating stall experimental study of a low-speed centrifugal compressor

对某低速离心压缩机无叶扩压器壁面静压波动和内部流场进行了详细的试验测量,重点研究了小流量工况下的不稳定流动和旋转失速。在试验中,首先使用高频动态压力传感器获得了不同流量工况下扩压器前盖板处的静压波动,并对测量结果进行了频谱分析,以确定旋转失速起始工况点和不同小流量工况下的失速频率。然后使用PIV测速设备详细测量了在失速条件下,无叶扩压器及叶轮流道内部的流场变化。试验丰富了对低速离心压缩机旋转失速流动现象的认识,为设计高性能的离心压缩机提供了丰富的实验数据。

Unsteady flows and rotating stall of a low-speed centrifugal compressor were investigated by measuring vaneless diffuser wall static pressure fluctuation and internal flow fields in detail at different small flow fluxes. Firstly the real time static pressure fluctuations on the vaneless diffuser shroud at different circumferential positions are acquired by high-frequency dynamic pressure transducers. DFT analysis is applied to the experimental results to ascertain the rotating stall beginning operation conditions and stall frequency. Then, the internal flow fields of the centrifugal compressor are investigated with a PIV （Particle Image Velocimetry） system at different small flow fluxes. The flow field development of vaneless diffuser and blade flow passage are given in detail at rotating stall conditions. The experiments enrich the understanding of rotating stall flow phenomenon of the low-speed centrifugal compressor and provide full experiment data for designing high performance centrifugal compressor.