泵间管气液两相流压力波传播速度数值研究

采用ANSYS CFX热相变模型数值模拟了泵间管气氧和液氧的混合冷凝过程.并应用整体平均两流体模型建立了气液两相流压力波的色散方程,系统研究了泵间管两相压力波的传播速度特性.计算表明:泵间管气液两相波速随空泡份额的增加先减小而后在弹状流区域略微增大,且两相波速随扰动角频率增加而增大.增加液氧流量或降低进口气氧温度,气液的冷凝效果增强,沿管流的空泡份额减小,气液两相波速增大. 

Numerical investigation on pressure wave propagation speed of gas-liquid two-phase flow in pump pipeline

Adopted thermal phase change model in computational fluid dynamics code ANYSY CFX, the mixing condensation process of gaseous oxygen and liquid oxygen in pump pipeline was numerically simulated. Moreover, the dispersion equation of two-phase pressure wave propagation was derived via the ensemble average two-fluid model, and was used to predict the pressure wave propagation speed in pump pipeline. The results indicate that with increasing void fraction the two-phase pressure wave propagation speed in pump pipeline first decreases and then slightly increases in slug flow, and the propagation speed increases as angular frequency enlarges. When liquid oxygen mass flow rate increases or inlet gaseous oxygen temperature decreases, the condensation effect of gaseous oxygen in pump pipeline enhances and the average void faction along the flow direction decreases, which produces large pressure wave propagation speed.