离心压缩机内进口导叶后面流场的实验研究

Experimental investigation of the flow field behind the inlet guide vane of the centrifugal compressor

在不同的进口导叶预旋角度下对一单级离心压缩机级进口导叶后面的流场进行了测量,分析了进口导叶预旋角度对流动及性能的影响。结果表明:在适当的流量工况下,选择不同方式的进口导叶预旋,可以使得压缩机级的运行得到优化。-20°预旋角是在设计扩压器进口安装角下使压缩机运行最理想的工况。由于叶轮旋转的影响,以及非对称形状的蜗壳在叶轮进口形成的不均匀的流场,使得在进口导叶零预旋时,叶轮进口的流动具有预旋,其同轴向的夹角约为10°。当体积流量减小时,由叶轮旋转和蜗壳形状引起的预旋角度也相应的减小。

The flow field behind the inlet guide vane （IGV） of the centrifugal compressor was measured under different IGV prewhirl angle, and the influence of IGV prewhirl angle on the flow field and performance was investigated. The results show that the operation range of the centrifugal compressor can be optimized if the IGV prewhirl angle is adjusted appropriately for different flow rate; and the prewhirl angle of - 20° can make the centrifugal compressor work at optimal condition under the design stagger angle of diffuser vane. Due to the rotation effect of the impeller and non-uniform force in the impeller inlet induced by the asymmetry shape of the volute, the impeller inlet flow angle is about 10° to the axial direction when zero IGV prewhirl angle is adopted ; and it decreases with the reduction of the volume flow rate.