膜丝非均匀排布中空纤维膜组件内流场的模拟

Simulation of the Flow Field Inside Hollow Fiber Membrane Modules with Non-uniform Fiber Packing

本文建立了中空纤维膜组件外压式死端过滤的纯水过滤CFD模型,模拟得到了膜丝不同装填方式下组件内流场以及组件的产水性能。以膜丝均匀装填的组件为参照对象,分别考察了膜丝装填由壳体向内逐渐紧密,由壳体向内逐渐稀疏,以及随机装填的三种组件。结果表明,各个组件不同位置的压力场差别较小,而速度场随着高度而变化;膜丝排布由组件壳体边缘向中心逐渐稀疏的组件产水效率高于其他三个组件,单膜丝平均产水流量比最小值高出约10.9%。

A CFD model of the outside-in dead-end pure water filtration within hollow fiber membrane modules has been developed.CFD simulation has been performed to obtain the flow field and water productivity of hollow fiber membranes with different fiber arrangement.With treating the module with uniform fiber arrangement as reference,three modules were investigated,with fiber arrangements of dense to sparse radially,sparse to dense radially,and random,respectively.Conclusions can be drawn that the pressure distribution changed a little with different locations and different modules,while the velocity distribution varied with locations in different modules.The module with the fiber arrangement of sparse to dense radially had the highest water productivity among the 4 modules which was approximately 10.9%higher than the lowest water productivity.