FST高效塔板传质元件内气相流场的数值模拟

FST高效塔板是一种喷射型塔板,同鼓泡型塔板相比,具有高通量、低压降等特点。塔板传质元件的结构会很大的影响塔板的传质效率和压降,为了优化塔板结构设计,提升塔板性能,有必要研究不同结构传质元件的效果。本文使用FLUENT软件对FST高效塔板传质元件开展数值模拟研究,得到传质元件内部气相流场,对比了3种结构传质元件内部气相流场的分布情况,考察了除雾叶片、旋流叶片径向角对气相流场的影响。结果显示除雾叶片会增强传质元件的除雾效果,降低塔板的雾沫夹带,但也会带来额外的塔压降。旋流叶片径向角会增强气相旋流强度,强化传质效果,但是也会带来压降过大、回流过大的问题。为优化设计塔板传质元件,应综合考虑各结构因素的影响,合理平衡塔板压降与传质效果、除雾效果。

CFD simulation of FST tray gas phase flow field

FST tray is one kind of spray tray.Comparing with bubble tray, it has higher flux and lower pressure drop.The tray structure influences mass transfer efficiency and pressure drop of the tray.In order to increase tray performance, different tray structures need to be investigated.A CFD model was developed by FLUENT to predict the gas phase flow field of FST tray.The gas phase flow fields of three different tray structures were compared and the effects of demist vanes and radial direction angle of rotating stream vanes were investigated.Results showed that demist vanes could decrease entrainment rate, but caused extra pressure drop.Rotating stream vanes with radial direction angle could increased swirling intensity, and enhanced mass transfer performance.However it would also increase pressure drop and backflow.Hence, in order to achieve optimal design, effects of structures should be considered comprehensively, and balance tray pressure drop, mass transfer performance and demist performance.