循环流化床换热器中液固二相流的数值模拟

摘要

在循环流化床换热器的流体中加入固体粒子,可以对边界层有扰动作用,加快换热器中的传质与传热.对流化床换热器中的液固二相进行数值模拟,分别讨论了固体粒子对液体动量方程、k-ε方程及能量方程的影响,在单液相方程的基础上进行修正,建立了相应的液固二相流控制方程,确定了物理模型及边界条件.利用FLUENT进行数值计算,分别讨论了固体颗粒加入量对液相流场、湍流动能、液相温度场的影响.模拟结果与实验结果一致.%Solid particles were added into the circulating fluidized bed exchanger to enhance the mass and heat transfer by agitating the boundary layer. The numerical simulation of liquid-solid two-phase flow was performed and the effects of solid particles on liquid moment equation, equation and energy equation were discussed respectively.The equations of liquid-solid two phase flow were established on the basis of corresponding modified liquid equations. The physical model and boundary conditions were set up. The calculation was carried out by means of FLUENT, and the effects of added particle amount on flow field, turbulence kinetic energy and temperature were investigated. The simulation result is concordant with the experimental result.