Numerical analysis of centrifugal compressor performance and flow at low Reynolds number

Three-dimensional numerical simulation was conducted for a low pressure centrifugal compressor at low Reynolds number. Influence of Reynolds number on the flow-field was analyzed. The results show that, the efficiency, rotating stall margin and flow capacity reduce with the decrease of Reynolds number. Change of the blade loading distribution reduces the working capability of the compressor. In the flow-field, the leading-edge separation is more obvious and the secondary flow is encouraged. Tip leakage losses of the splitter blade increases. The low velocity flow area near the suction surface of blade obviously increases and its beginning location also moves forward. These will also enhance the influence on the span-wise region.