带气腔的离心压缩机旋转失速的三维数值模拟

使用商业CFD计算软件CFX求解三维雷诺平均的Navier-Stokes方程组, 结合出口气腔模型对某带无叶扩压器的离心压缩机的旋转失速现象进行数值模拟.首先使用定常计算得到了该离心压缩机的稳态性能曲线, 并和实验测量值进行了比较.然后引入出口气腔模型, 模拟离心压缩机内的旋转失速流动.在小流量下, 从矢量图和径向速度等值线图中观察得到了离心压缩机内部流场的非定常流动现象.还研究了气腔模型不同参数对失速流动的影响, 结果表明气腔体积越大, 计算得到的失速频率越低. 

Three-dimensional numerical simulation of rotating stall inside a centrifugal compressor with plenum model

Numerical simulation results of rotating stall flow phenomenon inside a centrifugal compressor with vaneless diffuser by solving three-dimensional Reynolds averaged compressible N-S equations using commerce computational fluid dynamjcs(CFD) software CFX adopting RNG k-ε turbulence model are presented in this paper.Firstly,the steady performance curve is obtained using steady calculations and compared with experimental results. Secondly,a plenum chamber model is added at the vaneless diffuser outlet to simulate the rotating stall flow phenomenon inside the centrifugal compressor.The paper gives the centrifugal compressor internal flow fields at different times during the stall cycle at the least mass flow rate and observes the stall flow phenomenon.The plenum chamber influence on the rotating stall is also investigated.The simulation indicates the more the plenum chamber volume,the lower the stall frequency.