The fine particles produced by coal-fired boilers have become the main source of air pollution.As fine particles size is very small,the traditional dust removal device can not remove it effectively.As a new method,turbulence agglomeration can promote the growth of fine particles and remove them effectively.The κ-ε turbulence along with population balance model (PBM) is used to study the effect of the clustering of fine particles behind the turbulent cylinder.In this paper,the effects of velocity,volume fraction of particles and stokes(St) number of inlet particles on agglomeration of particles are mainly discussed.The simulation results show that the larger the velocity is,the greater the turbulence energy dissipation rate is,and the agglomeration effect of the particles is better.By increasing the volume fraction of inlet particles,it will increase the probability of particle collisions and promote the aggregation of particulates.The smaller St number of the inlet particles are,the smaller the initial particle sizes of the particles are.Good followability of small particles will follow the flow of fluid entrained by the vortex,and the effect of particle aggregation is much better.%燃煤锅炉产生的细颗粒物已经成为大气污染的主要来源,由于烟气中的颗粒物粒径较小,传统除尘器难以对其进行有效脱除.利用湍流团聚对含尘烟气进行预处理是一种促进细颗粒长大,进而有效脱除细颗粒物的新方法.采用κ-ε湍流模型耦合颗粒群平衡模型(PBM)对扰流圆柱后方细颗粒物的聚并效果进行了研究.着重讨论了速度、颗粒的体积分数、入口颗粒的斯托克斯数(St)数对颗粒团聚效果的影响.模拟结果表明,速度越大,湍动能耗散率也越大,颗粒的团聚效果较好;增加入口颗粒的体积分数,提高了颗粒碰撞的几率,对颗粒物的聚集有促进作用;入口颗粒的St数越小,颗粒的初始粒径越小,小颗粒较好的跟随性会跟随流体的流动被漩涡所卷吸,颗粒聚并效果越显著.
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