Abstract
In order to improve the performance and operating range of centrifugal compressors, it is indispensable to understand unsteady behavior of vortical flows. In this study, the flow fields at different rotational speed in a transonic centrifugal compressor with single splitter blades have been investigated by Detached Eddy Simulation(DES). The simulation showed that the detached shock wave ahead of full blade, which interacts with the tip leakage vortex as well as the suction surface of adjacent full blade, became strong with a rise in rotational speed, so that the shock wave caused the tip leakage vortex breakdown in almost all pitches. Moreover, it was found that early occurrence of the vortex breakdown at higher flow rate led to a reduction in operating range.
