喷动-流化床整体式多喷嘴效应CFD模拟

CFD Simulation of Gas-Solid Flow Behavior in a Spout-Fluidized Bed With Integral Multi-Nozzle Effect

建立一种整体式多喷嘴喷动-流化床结构,采用双流体模型(CFD)对其内气-固两相流动进行数值模拟,在传统柱锥型喷动床锥体对称的两侧开若干缝隙,形成辅助多喷嘴喷动床,使其产生喷动-流化床的效果。通过CFD数值模拟获得多喷嘴喷动-流化床内颗粒体积分数、颗粒速度及空隙率等,并将模拟结果与单喷嘴喷动床进行对比,数值模拟证明了整体式多喷嘴喷动-流化床结构的可行性。与常规喷动床相比,整体式多喷嘴喷动-流化床能够有效增强喷动床内气-固两相流动,并且加强了单喷嘴喷动床环隙区底部颗粒运动死区的流动,同时省略了旁路供气辅助设备。

Flow behaviors of gas and particles were numerically simulated in a novel integral multinozzle spout-fluidized bed using an Eulerian-Eulerian two-fluid model（TFM）on the basis of kinetic theory.A number of slits were formed on the cone side of spouted bed to form an auxiliary multinozzle structure so as to create a spoiler effect on the boundary of the pyramidal boundary.Through CFD numerical simulation,the distribution of particle concentration,particle velocity and void fraction in the spouted bed were obtained,and the simulation results were compared with those of a single-nozzle spouted bed.Compared with the conventional spouted bed,the multi-jet spoutfluidized bed can effectively enhance the gas-solid two-phase flow in the reactor,strengthen the movement of particles in the dead zone at the bottom and annulus of the spouted bed,and the bypass gas auxiliary equipment is omitted.