机匣引气再循环拓宽压气机工作范围的仿真研究

Simulation on expanding steady working range of centrifugal compressor by self-recirculation casing treatment

高压比离心式压气机高效率工作范围窄,喘振裕度低。为了拓宽其高效工作范围,将机匣引气再循环技术应用于高压比离心式压气机。采用数值模拟方法对其进行仿真研究,对各结构尺寸对压气机性能的影响进行对比。结果表明,引气再循环系统使该离心压气机各转速下稳定工作范围平均拓宽13%以上,喘振裕度最大增加11%。抽吸槽与分流叶片的距离在引气再循环结构尺寸中对离心压气机性能影响最大,其次是抽吸槽的宽度,其余结构尺寸对其影响较小。引气再循环使压气机叶轮入口相对马赫数分布更加均匀,减弱叶片前缘局部高马赫数的现象,使叶片入口正攻角减小,抑制了叶片表面边界层的分离。

Numerical simulation method is adopted to simulate and research self-recirculation casing treatment （ SRCT ） on expanding the scope of steady work of high-pressure-ratio centrifugal compressor , and increase the compressor surge margin .Contrast the influences which are caused by structure sizes of the SRCT on the perform -ance of compressor .The results showed that SRCT makes the compressor stable operating range broaden more than 13%in average on all kinds of speed , and the surge margin has increased by 11%at most.Among the structure si-zes, the distance between the bleed slot and the splitter blade has the largest effect on the performance of centrifu -gal compressor , followed by the bleed slot width , others have less affect .SRTC makes the distribution of the com-pressor impeller inlet relative Mach number more uniform , weakens the phenomenon of local high Mach number of blade leading edge , decreases the positive incidence of blade inlet , and inhibits separation of the blade surface boundary layer .