带有孔式机匣的离心压气机非定常数值模拟

对半开式离心压气机提出了孔式机匣处理方式并对近失速点工况下的流场进行了非定常的数值模拟.分析计算结果发现，抽吸孔对叶顶区域的低能量流体有抽吸作用，造成叶顶区域尤其是叶顶间隙内对应抽吸口位置出现压力波动区域.抽吸孔内的抽吸气流重新进入压气机入口，不仅可以增大压气机入口的局部流量，而且具有时间和空间上的周期性，对压气机入口叶顶区域的流动形成周期性的激励，使得压气机入口叶顶区域的流动也具有周期性.孔式机匣处理方式主要影响的是压气机叶片顶端的剪切流动区域，干扰了叶顶间隙内的流动，造成压气机稳定工作范围的扩大.

Unsteady Simulation of a Centrifugal Compressor with Holed Casing

Holed casing treatment was proposed for unshrouded centrifugal compressor and unsteady simulation was done in small flowrate condition near rotating stall. It was found that the pressure near the bleed port fluctuates in the tip region. The inlet flowrate of the compressor can be raised by the reinjected flow in the holes. A periodical excitation to the inlet flow of the compressor is also induced because of the space periodicity and time periodicity of the reinjected flow, and the flow in the tip region near the blade leading edge is periodic. The shear flow in the tip region of the compressor is improved and the flow in the tip clearance is interfered by holed casing treatment, and the stable working range of the compressor is expanded as a result.