绕平板气液两相流数值计算方法

为探究现行多相流模型和湍流模型对通气两相流动的适应性及所体现的数理本质，选取典型的绕平板气液两相流为研究对象，通过对比不同多相流模型、湍流模型对绕平板气液两相流的数值计算结果与实验结果，建立了适用于绕平板气液两相流的数值模型。 结果表明，基于单流体理论的Mixture多相流模型忽略了流场内客观存在的气-液相界面，计算结果不能真实反映实际流动现象，与实验结果不符；Level Set方法由于考虑了气液界面的表面张力的影响，能合理反映气液界面波动的特性，可以获得和实验较为一致的计算结果；滤波器湍流模型在标准k-ε模型的基础上，通过对湍流黏性项的修正，降低了计算流场中的湍流黏度，可以更精细地描述与时间相关的气液多相复杂流动现象，进而有效提高对非定常流动计算过程的预测精度。 

Numerical Study on Multiphase Flows Around a Plane

In order to address the adaptation of the current multiphase flow model and turbulence model to the computations of ventilated multiphase flows and its physical meaning, the numerical simulation of the multiphase flows around a plane was studied and a numerical simulation method was evaluated. It is revealed that, the Mixture model which is based on the idea of single-fluid, has ignored the existing gas-fluid interface, resulting the inconsistency with the experimental results. Due to taking the surface tension into consideration, the Level Set method is able to reflect the fluctuation of interface properly and get a quite consistent result with the experimental results. Based on the standard k-ε model, the filter based model (FBM) decreases the coefficient of the turbulent viscosity by its factor modification, and can also describe subtly the time correlation phenomena of ventilated multiphase flows, so that the better precision of unsteady multiphase flow can be attained.