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基于相似理论为某一三级轴流式低速压气机增加一个高效零级使压气机流量增加了12.5%,同时达到增加压比的目的。由于流动缺陷集中在静叶上,利用三维粘性计算流体力学(Computational fluid dynamics,CFD)技术对静叶进行重新改型设计:采用可控扩散叶型(Controlled diffusion airfoil,CDA)控制叶片表面速度分布,控制了叶片表面附面层厚度,尾缘逆压梯度减小,很大程度减小了叶栅后半部分的三维分离;为进一步缓解端壁处的低能流体堆积,采用端弯技术,在改善端区流动的同时也很好的改善与原机的匹配,提高零级性能,最终提高新型压气机的效率,达到设计要求。同时分析加零级前后压气机特性曲线,证实喘振裕度得到了保证,分析进出口气流角表明加级后原机部分仍然保持原来的相似运行条件。
Based on the similarity theory, a high-efficiency zero-order compressor is added to a three-stage axial low-speed compressor to increase the compressor flow by 12.5% and achieve the purpose of increasing the pressure ratio. Due to the flow defects concentrated on the vanes, the vane is reformatted by using three-dimensional Computational Fluid Dynamics (CFD) technique: Controlled diffusion airfoil (CDA) is used to control the blade surface velocity distribution , Which controls the thickness of the overlay on the blade surface and decreases the back pressure gradient, which greatly reduces the three-dimensional separation of the second half of the cascade. In order to further reduce the accumulation of low-energy fluid at the end wall, Improve the end of the flow but also a good match to improve the original machine to improve the zero-level performance, and ultimately improve the efficiency of the new compressor to meet the design requirements. At the same time, the characteristics of the compressor before and after zero-point addition were analyzed to confirm that the surge margin was guaranteed. Analyzing the inlet and outlet airflow angles showed that the original machine part still maintained the original similar operating conditions.