气液两相流数值求解过程中虚假流动问题研究

Spurious Currents during Numerical Simulation of Gas-liquid Two-phase Flow

基于静止液滴问题,对气液两相流数值求解过程中的虚假流动问题进行了研究。对虚假流动的涵义和特征进行了描述和分析,研究了表面张力、液体粘度等因素对虚假流动的影响。研究发现,计算域中虚假速度平均值与计算时间之间存在特定函数关系,并通过曲线拟合给出了相应的函数表达式,从而为虚假流动的削弱和消除提供了一个方法。分析了虚假流动成因,指出相界面迁移过程追踪方法的改进可有效削弱虚假流动现象,并通过CLSVOF方法与VOF方法模拟结果的对比对该结论进行了验证。

The spurious currents were studied based on the stationary droplet problem.The conception of spurious currents and their characteristics were described.The effect of surface tension and liquid viscosity on spurious currents was analyzed.It was found that there was a certain relationship between the average spurious velocity and the computing time.This conclusion could provide an idea to weaken or eliminate the spurious currents.The cause of the spurious currents was analyzed and found that the modification of the phase interface simulation method could weaken spurious currents obviously,and this conclusion was validated by the comparison of the simulation results of CLSVOF method and VOF method.