旋风除尘器流场及浓度场实验与模拟

在研究旋风除尘器内气固两相的运动状况及分离机理方面,计算机模拟替代部分实验的方法能够优化设计旋风除尘器结构参数,提高其对微细颗粒的捕集效率,减少运行压力损失。本研究采用RSM模型和随机轨道模型对旋风除尘器内流场及浓度场进行模拟及实验。研究表明,旋风除尘器压力损失模拟结果与实验结果吻合较好,对于大于5μm的颗粒其捕集效率模拟结果与实验结果基本吻合;旋风除尘器外壁的颗粒浓度呈螺旋带状分布;如将排气管管径减少至原直径0.8倍,可使其对2μm颗粒捕集效率提高6.6%,但压力损失提高36.5%;颗粒的凝并作用有利于提高旋风除尘器微细颗粒的捕集效率。

Experimental and simulation study on flow field and concentration field of cyclone

In studying gas-particle movement and separation mechanism in the cyclone, the computer simulation instead of parts of experiment can be used to optimize structural parameters, improve the collection efficiency of fine particle and reduce operating pressure drop. The Reynolds stress model and stochastic particle-tracking model were adopted to simulate flow field and concentration field in a cyclone separator. The results showed that the pressure numerical simulation results agreed well with the experimental ones, and its collection efficiency simulation results were basically consistent with the experimental results for particles larger than 5 microns; particles concentration showed helix solid strand distribution in the collecting zone; 2-micron particle collection efficiency could be improved 6.6% by decreasing exhaust pipe diameter to 0.8 times of the original diameter, but pressure drop increased 36.5%; particle coagulation could play an important role in improving the collection efficiency of fine particles in cyclone.