倾斜波纹板上液膜流动的CFD研究

CFD simulation of liquid film flow on inclined wavy plates surface

利用VOF法建立了液膜在倾斜波纹板上的气 液两相流 CFD模型, 并根据液膜流动特点提出了表面张力动量源项和气液界面作用力动量源项. 模拟结果与文献实验值吻合较好, 表明本文提出的 CFD液膜流动模型具有一定的可靠性. 通过模拟不同性质的液体在不同表面结构波纹板上的流动过程发现, 波纹板表面微观结构以及液体性质尤其是液体的表面张力对连续液膜的形成有重要作用, 表明通过改变波纹板面微观结构以及降低液体的表面张力可以促进连续液膜的形成, 对提高气液之间的传质效率有重要意义.

The liquid flow behavior on the structured packing sheet can be regarded as the liquid film flow on an inclined wavy plate. A better understanding of the hydrodynamics of this kind of flow enables development of optimal packing surface with good wetting ability for improving mass transfer efficiency, A two-phase flow CFD model using the volume of fluid (VOF) method was presented for predicting the hydrodynamics of the falling film flow on the inclined wavy plates, where two momentum source terms, surface tension and interface stress shear were considered. The simulated results agreed well with the experimental results from Ref. [1] and [2], which showed that the CFD model used was reliable. Using the proposed CFD model, the flow behavior of liquids with various properties on different wavy plates were investigated. It was shown that changing the microstructures of wavy plates or reducing liquid surface tension would improve the formation of a continuous liquid film, which was significative for improving the mass transfer efficiency between gas and liquid.