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为揭示多级压气机中上下游叶轮对中间叶片叠加气动影响特性,阐述不同叠加干涉情况下下游叶轮进气角度变化,采用数值方法模拟了一级轴流和一级离心组成的组合压气机非定常流场。详细讨论了上游动叶尾迹和下游动叶势流对中间导流叶栅段气流非定常流动的异频和同频叠加干涉特性,依据计算结果,直观地展示了静叶通道中两种干涉间相互激励和抑制作用的位置和时间,与数学公式的推导结果相互印证。研究结果表明:当上下游动叶对中间静叶段异频干涉时,干涉的激励、抑制区域的轴向位置随时间发生变化;当上下游动叶对中间静叶干涉频率相同时,干涉的相互激励、抑制区域的轴向位置不随时间发生变化,但干涉的激励、抑制区域的轴向位置受时序位置影响。另外,上游动叶尾迹与下游离心叶轮势流的不同叠加情况,决定着下游离心叶轮进口相对气流角的大小及波动幅值。
In order to reveal the superimposed aerodynamic characteristics of the middle and lower impellers in the multi-stage compressor, the variation of the inlet angle of the downstream impeller under different superimposed interferences was expounded. The numerical simulation was performed on a combined compressor with primary axial flow and primary centrifugal flow Constant flow. In this paper, we discuss in detail the different frequency and the same frequency superimposed interference characteristics of unsteady flow of the upper moving blade wake and the downstream moving blade flow on the mid-flow guideway. According to the calculation results, two kinds of interference The location and time of interaction and inhibition between each other and the deduction result of mathematical formula are mutually proof. The results show that when the upper and lower moving blades interfered with the middle stator blade, the axial position of the restraining area changed with the time when the interfering excitation and the interference frequency were the same, Mutual excitation, inhibit the axial position of the region does not change over time, but the interference excitation, inhibition of the axial position of the region affected by the timing position. In addition, the superimposition of the wake of the upstream rotor blade and the potential flow of the downstream centrifugal impeller determines the magnitude and amplitude of the relative airflow angle at the inlet of the downstream centrifugal impeller.