Study of the Effect of Clearance Variation on Flow Field at the Top of Blade of an Axial Compressor Rotor under Near-stall Condition
In order to further understand the influence of clearance variation on the flow field structure of the top of blade of an axial compressor rotor under the near-stall condition,the axial compressor rotor Ro-tor37 was taken as the object of study,and its flow field at the top of blade was numerically simulated in both steady and unsteady forms.The calculation results show that with the reduction of the clearance at the top of blade,the total pressure ratio and isentropic efficiency of the compressor are improved,and the stable operation range is enlarged;under 2 times of the design clearance,the tip leakage vortex is ex-panded and broken by the action of excitation wave,which blocks the inlet flow channel and induces the compressor to clog and stall;under half of the design clearance,the flow separation of the suction surface is intensified,backflow occurs,part of the backflow interferes with the incoming flow upstream of the front edge of the pressure surface front,and the inlet blockage is intensified,resulting in part of the in-coming flow overflowing from the front edge,inducing the compressor tip stall;the dominant factors of the stall process of the compressor with different clearances are different,the stall under the large clearance is caused by the unsteady fluctuation of the tip leakage vortex crushing,while the stall under the small clearance is mainly dominated by the cyclic leading edge overflowing induced by the flow separation.
axial compressorunsteady flowclearance at the top of bladetip leakage vortex
万方数据
维普
