OpenFOAM Simulation and Verification of Droplet Separation in Baffles
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摘要: 为预测折流板中的气液两相流行为,使用OpenFOAM基于Euler-Lagrangian方法以液滴为离散相、气流为连续相模拟了折流板中离散相与连续相双向耦合的流动。其中离散相受曳力作用,连续相分别使用了标准k-ε模型与k-ω SST模型进行模拟。本文介绍了网格的划分,对于OpenFOAM生成的Lagrangian粒子坐标的后处理以及基于OpenFOAM编写的折流板汽水分离效率程序。计算得到不同湍流模型在不同网格下的连续相流场、连续相速度场以及汽水分离效率与实验数据的对比。结果表明,无论是连续相还是离散相,湍流模型相较于网格对于结果的影响更大,k-ω SST模型计算结果更加准确,模型对于大尺寸直径的液滴分离效率预测准确,但是对于小直径液滴的分离效率预测不够准确。Abstract: In order to predict the gas-liquid two-phase flow behavior in a baffle, OpenFOAM based Euler-Lagrangian method was used to simulate the two-way coupling flow of discrete and continuous phases in a baffle, with liquid droplets as the discrete phase and gas flow as the continuous phase. The discrete phase is subject to the drag force, and the continuous phase is simulated using the standard k-ε model and the standard k-ω SST model respectively. This article introduces grid meshing, post-processing of Lagrangian particle coordinates generated by OpenFOAM, and a program based on OpenFOAM for baffle steam water separation efficiency. The continuous-phase flow field, continuous-phase velocity field and steam water separation efficiency of different turbulence models under different grids are calculated and compared with the experimental data. The results show that the turbulence model has a greater impact on the results than the grid, whether it is continuous phase or discrete phase, and the calculation results of k-ω SST model are more accurate. The model can predict the separation efficiency of large diameter droplets accurately, but cannot predict the separation efficiency of small diameter droplets accurately enough.
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Key words:
- Baffle plate /
- OpenFOAM /
- Gas-liquid two-phase flow /
- Separation efficiency /
- Turbulence model
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图 1 算例的折流板几何结构[5]
Figure 1. Geometry of Baffles
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