基于VOF方法模拟离心式喷嘴内部流动过程

基于两相界面追踪方法VOF(volume of fluid)模拟了离心式喷嘴内部的流动过程,得到了液相填充喷嘴内部的过程,初始时刻,气液界面出现褶皱,随着进入液体的增多,褶皱逐渐消失;着重分析了喷嘴各个部位速度、压力分布,由于气液两相的存在,喷嘴内部流场变得异常复杂,流场分布不能用单相流的模式分析,总压损失大部分存在于喷嘴收缩段以及直管段,增大收缩段锥角、减小收缩段长度有利于减小总压损失;在喷嘴出口处设置一定扩张角,能够增加液相速度,减小液膜厚度,有利于雾化. 

Numerical simulation of flow field in pressure-swirl injector based on VOF interface tracking method

Interface-tracking method volume of fluid (VOF) was used to simulate the flow process in pressure-swirl injector.The process of liquid phase filling injector was exhibited:pucker appears at first,then distinguishes with the increase of liquid.Velocity and pressure distribution were especially analyzed in different sections of injector.As both liquid and gas phase coexist in the injector,the flow field is highly complex.Total pressure loss lies mostly in the convergent and columned sections,so increasing convergent angle helps to reduce total pressure loss.Setting a divergent angle at injector exit can increase liquid phase velocity and reducing liquid sheet thickness can get better atomization finally.