粉体抽气除尘的流场分析与模型仿真

Flow Analysis and Numerical Simulation of Powder Dusting under Pumping

粉体下料过程中产生的粉尘会对环境、员工造成影响。为此在给袋式粉体充填设备上设置了粉体除尘罩。一方面对除尘罩内部的粉尘颗粒进行受力分析,得到了负压场会以气流曳力形式作用在颗粒上;通过分析流体雷诺数,确定气流速度是影响粉尘收集的本质因素。另一方面通过Fluent模拟颗粒轨迹和探究合理的抽气速度。发现气流风速过小时,不足以带动部分粒径的颗粒上升,反而增加了罩口粉尘的悬浮量;过大的风速则使大颗粒粉尘不易沉降。而当抽气速度为26-39m/s时,除尘效果最佳。

There are influences for environment and workers during powder packaging. So the automaticbag packaging machine of powder adds a dusting system. On the one hand,the process analysis was taken forparticles in dust hood and the minus pressure,in the form of drag force of air,affect particles. What, s more,byanalysing fluid Reynolds Number the air velocity is confirmed as a fundamental factor affecting dusting. On theother hand,fluent is used to stimulate particles tracking and explore reasonable pumping velocity. When the ve-ocity is too small to rise some part of particles,it adds suspended particles at the mouth of dust hood. And theexaggerate velocity also make the large particles suspended, which is difficult to fall. When the pumping veloci-ty reach to 26 -39m/s the best effect to dusting.