Rotating instability as an unsteady flow phenomenon is closely related to rotating stall in the compressor. In this paper, dynamic pressure measurements and full-annular URANS simulations were conducted in a subsonic axial flow compressor rotor to enhance the understanding of the flow mechanism of RI. RI characterized by a frequency band in the spectrum is detected at a narrow stable operating range in the experiments. The monitoring results from simulations show that RI characterized by a frequency hump in the spectrum appears near stall condition which is consistent with the observation in the experiments. RI shifts to lower frequency band in the rotating frame with the decrease of mass flow rate. Details of the numerical flow field indicate that RI develops synchronously with the oscillation of the tip leakage flow (TLF). The tip leakage vortex (TLV) forms a low static pressure near the pressure surface side of neighboring blade through an induced vortex. It varies the tip aerodynamic loading. Both the tip aerodynamic loading and TLF get strong with the decrease of mass flow rate. The stronger TLV will form a stronger induced vortex near the pressure surface side of the neighboring blade and propel the induced vortex toward the leading edge of blade. When a high tip aerodynamic loading region is influenced by the induced vortex near the pressure surface side, the intensity of TLF in the next passage will be weakened. Then, TLF fluctuates and leads to the oscillation of neighboring blade tip aerodynamic loading as well as the oscillation of TLF issuing from the neighboring blade. The circumferential propagation of this influence process results in RI.

作为不稳定流动现象的旋转不稳定性与压缩机中的旋转失速密切相关。在本文中，在亚音速轴流压气机转子上进行了动态压力测量和全环形URANS仿真，以增强对RI流动机理的了解。在实验中，在狭窄的稳定工作范围内检测到以频谱频带为特征的RI。模拟的监测结果表明，以频谱中的频率驼峰为特征的RI出现在失速条件附近，这与实验中的观察结果一致。随着质量流率的降低，RI移至旋转框架中的较低频段。数值流场的详细信息表明RI与尖端泄漏流（TLF）的振荡同步发展。尖端泄漏涡流（TLV）通过感应涡流在邻近叶片的压力表面侧附近形成低静压。它改变了尖端的空气动力学负荷。随着质量流率的降低，尖端空气动力学载荷和TLF都变强。较强的TLV将在邻近叶片的压力表面侧附近形成较强的感应涡流，并将感应涡流推向叶片的前缘。当高尖端空气动力学负载区域受压力表面侧附近的诱导涡流影响时，下一通道中的TLF强度将减弱。然后，TLF波动并导致相邻叶片尖端空气动力载荷的振荡以及从相邻叶片发出的TLF的振荡。该影响过程的周向传播导致RI。