格子Boltzmann方法的竖壁汽液降膜数值研究

Numerical Simulation of Falling Liquid Film Based on Lattice Boltzmann Method

对原有的格子Boltzmann伪势模型进行了改进,提出表面张力可调的伪势模型,并基于改进后的伪势两相模型在二维条件下模拟了雷诺数为5、10和20时竖壁降膜的流动,进一步研究了液膜在入口处存在正弦扰动时的流动特性,分析了入口扰动和表面张力作用对液膜稳态波动的影响,总结了液膜稳态波动的规律.结果表明:数值计算得到的流形拓扑及波动特征与实验结论能较好地吻合,表明伪势模型能够较为真实地反映降膜流动的物理过程.

A two-phase Shan-Chen model with adjustable surface tension was proposed by improving the original lattice Boltzmann model,based on which falling film flow was simulated under 2-dimensional conditions respectively under Reynolds numbers of 5,10 and 20,so as to further study the flow characteristics of film with inlet disturbance,analyze the influence of external disturbance and surface tension on the steady-state wave motion,and to summarize the tendency of steady-state film development.Results show that the flow morphology acquired through numerical calculation is in good agreement with experimental data,demonstrating that the Shan-Chen model is capable of reflecting the physical process of falling film flow.