Effect of structured packing's structure on liquid distribution by computational fluid dynamics

doi:10.16085/j.issn.1000-6613.2015.11.008

Abstract

Abstract: A volume of fluid multiphase-flow model for two adjacent sheets of structured packing was used to investigate the effect of structure of structured packing on liquid distribution in meso-scale. The three-dimensional computational fluid dynamics (CFD) simulation visualized liquid distribution, and the results showed good agreement with the existing correlation for effective area. Numerical simulation results showed that both angle of inclined corrugation to the horizontal and micro-structure of surface played significant roles in liquid distribution and flow pattern on structured packing surface, while specific area of packing had little influence. Under a specific liquid load, better liquid distribution and hydrodynamic performance were found on the Y-type of structured packing with larger specific area and coarser surface.

Key words: computational fluid dynamics (CFD), multiphase-flow, mesoscale, structure of structured packing, liquid distribution, flow pattern

摘要： 提出了一种新型的拟循环边界条件,并采用计算流体力学(computational fluid dynamics,CFD)中VOF(volume of fluid)多相流模型对液相在两相邻规整填料特征单元上的分布进行三维仿真模拟,数值模拟结果与已有经验公式具有较好的吻合性。从介尺度的角度出发,系统地研究了规整填料的宏观结构和微观结构对液相在规整填料片上分布的影响。结果表明:规整填料的波纹倾角和表面微观结构对液相特别是低表面张力物系在规整填料内的流动形态有很大的影响,而比表面积对液相在规整填料内的流型几乎无影响。相同液相流率下,液相在高比表面积、填料表面有波纹的Y型规整填料片上的分布较好,具有较好的流体力学性能。

关键词: 计算流体力学, 多相流, 介尺度, 规整填料结构, 液相分布, 流动形态

CLC Number:

TQ028.8

TAN Liyuan, YUAN Xigang, KALBASSI Mohammad Ali. Effect of structured packing's structure on liquid distribution by computational fluid dynamics[J]. Chemical Industry and Engineering Progree, 2015, 34(11): 3869-3878.

谭丽媛, 袁希钢, KALBASSI Mohammad Ali. 规整填料结构对液相分布影响的计算流体力学[J]. 化工进展, 2015, 34(11): 3869-3878.

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