气液两相下离心泵流动特性研究

Study on the Flow Characteristics of the Centrifugal Pump Under Gas-liquid Two-phase Flow

基于CFX软件中的Eulerian-Eulerian非匀相流模型,对某型离心泵内部流动特性进行仿真模拟。结果表明:随着进口含气率增加,叶轮流道内流体分布不均匀度增加,叶轮对流体做功能力下降,同时离心泵叶轮流道会出现气体积聚区域,且部分流道被气体严重堵塞;气液两相工况下,叶轮流道内会产生较大的涡旋,随着进口含气率增加,叶轮流道内的流体湍动程度及涡旋扩散范围也随之增大,造成泵的扬程、效率降低。

Based on the Eulerian-Eulerian inhomogeneous multiphase flow model in the CFX software,the flow internal characteristics of the centrifugal pump were simulated. The results showed that, with the increasing of IGVF(inlet gas volume fraction),the unevenness of the fluid distribution in the impeller flow channel increased, and the impeller’s ability to work on the fluid decreased.There were some gas accumulation areas in the flow channel of the impeller, and part of the flow channels were seriously blocked by gas. Under the gas-liquid two-phase condition, large vortexes were generated in the impeller channels. The degree of the fluid turbulence and the range of vortex diffusion in the impeller flow channels gradually expanded with the increasing of IGVF, resulting in a decrease in the pump head and efficiency.