氮气压缩需要离心式压缩机在相对较高的环境压力下运行。采用商业软件CFX-SOLVER，基于SST k-ω 湍流模型,对某型离心压气机进行了全通道稳态和瞬态数值模拟，建立基于时间动态变化的压缩机进出口流动模型，耦合全通道数值方法捕捉扩压器内旋转失速的动态发展过程。结果表明，随着节流过程的进行，扩压器入口表现出明显的非定常现象。在入口处监测出强烈的压力脉动，受流动分离和强逆压梯度的影响在扩压器前缘卷起龙卷涡触发扩压器失速，且第二级扩压器中失稳特征的出现早于第一级扩压器，每一级扩压器失速区的传播方向均与叶片旋转方向相同，传播速度分别为4.348%、5.26%叶轮旋转转速。

Nitrogen compression requires centrifugal compressors to operate at relatively high ambient pressure. Based on the SST k-ω turbulence model, the full-channel steady-state and transient numerical simulation of a centrifugal compressor is carried out by using the commercial software CFX-SOLVER. The compressor inlet and outlet flow model based on time dynamic change is established, and the dynamic development process of rotating stall in the diffuser is captured by coupling the full-channel numerical method. The results show that during the throttling process, the diffuser inlet exhibits an obvious unsteady phenomena. A strong pressure pulsation was monitored at the inlet. Due to the influence of flow separation and strong adverse pressure gradient, a tornado vortex was rolled up at the leading edge of the diffuser to trigger the stall of the diffuser, and the instability characteristics of the second stage diffuser appeared earlier than that of the first stage diffuser. The propagation direction of the stall zone of each stage diffuser is the same as the rotation direction of the blade, and the propagation speed is 4.348 % and 5.26 % respectively.

黑龙江省重点研发计划资助（GA23A907）；中央高校基本科研业务费专项资金资助（NO. 3072025CFJ0307）