脱硫吸收塔深度除尘气液两相流数值模拟研究

Numerical Simulation on Gas-liquid Two-phase flow in Deep Dust Removal of Desulphurization Absorption Tower

脱硫吸收塔内部流场较为复杂,涉及到气液固三相介质流动。CFD(计算流体动力学)数值模拟采用欧拉多相流模型和DPM(离散相模型),主要用于分析气液两相速度场及温度场的分布情况。研究结果表明:气液两相相对速度越大,液滴对颗粒物的惯性捕集效率就越高,有利于微米颗粒物在塔内的捕集;气液两相温差越大,液滴对颗粒物的热泳捕集效率就越高,有利于亚微米颗粒物在塔内的捕集;但相对速度和温差较大的区域,液滴体积分数较低。

Involving gas,liquid,and solid flow,the internal flow field of the FGD(flow gas desulfurization)absorption tower is complex.CFD(computational fluid dynamics)numerical simulation adopts Euler multiphase flow model and DPM(discrete phase model)to analyze velocity field and temperature field distribution of gas-liquid two-phase flow.The results show that the higher the relative velocity of gas-liquid flow is,the higher the inertial capture efficiency of droplets is,which is beneficial to the capture of micron particulates in the tower;the larger the temperature difference between gas and liquid phases is,the higher the thermophoresis capture efficiency of droplets is,which is beneficial to the capture of submicron particulates in the tower.However,the volume fraction of droplets is lower in regions with larger relative velocity and temperature differences.