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为进一步加深对轴流压气机转子叶尖间隙内泄漏流/涡流动结构的认识,针对某台用于高压压气机低速模拟的四级重复级大尺度轴流压气机上的转子,采用定常数值方法开展了详细的研究。首先用已有的试验结果校核了计算方法的可靠性,随后研究了设计点工况下端区复杂流动结构和流动损失的机理,最后比较了无叶尖间隙和不同叶尖间隙大小的轴流压气机转子端区流动结构的差别,以及设计点和近失速情况下叶尖泄漏涡结构、泄漏流/主流交界面、端壁堵塞以及端壁损失的区别。结果表明,在62.5%间隙高度以下的叶尖区域内,从前缘叶尖间隙流出的流体会卷吸成叶尖泄漏涡,且随间隙高度的增加其占据的叶尖泄漏涡的位置由内而外;而在62.5%间隙高度以上,从转子前缘间隙内流出的流体不会卷吸成叶尖泄漏涡,随间隙高度的增加流动受叶尖泄漏涡的影响越来越小,更易出现二次及多次泄漏,且所占据的弦长范围也更宽广;设计状态下,叶尖泄漏涡在向下游发展的过程中会逐步膨胀,并与主流强烈掺混,无量纲流向涡量迅速减小,但无量纲螺旋度值显示其仍能保持集中涡的特征。
In order to further deepen the understanding of the leakage flow / eddy flow structure in the tip clearance of the axial compressor rotor, a constant-value method was used to simulate the rotor of a four-stage repetitive large-scale axial-flow compressor for low-speed high-pressure compressor simulation. Carried out a detailed study. First of all, the reliability of the calculation method is verified by the existing test results. Then the mechanism of the complex flow structure and flow loss in the lower end of the design condition is studied. Finally, the axial flow without tip clearance and different tip clearances is compared The difference of the flow structure of compressor rotor end zone and the difference of tip leakage vortex structure, leakage flow / mainstream interface, end wall plugging and end wall loss at design point and near stall. The results show that in the tip area below 62.5% clearance height, the fluid flowing out from the tip tip clearance entraps into the tip leakage vortex, and the position of the tip leakage vortex occupied by the clearance height increases from the inner While the fluid flowing out from the rotor front clearance will not be entrained into the tip leakage vortex above 62.5% clearance height. The flow leakage caused by the tip leakage vortex is getting smaller and smaller as the clearance height increases, Times and multiple leaks, and occupy a broader chord range; under the design state, the tip leakage vortex will expand gradually in the process of downstream development and strongly blend with the mainstream, and the dimensionless flow direction vorticity rapidly decreases Small, but dimensionless helicity values indicate that they can still retain the characteristics of concentrated vortices.