低低温工况下颗粒凝并机理分析及研究方法初探

Mechanism Analysis and Research Methods of Particle Coagulation Under Low-Low Temperature Condition

低低温电除尘器可有效提高颗粒凝并,在文献调研及相关研究的基础上,对低低温工况条件下颗粒凝并的机理进行了分析,给出了一种理论计算与实验观测相结合的研究方法。该方法利用2d-LES模型模拟湍流流场,利用离散相模型(DPM)计算烟气冷却器中颗粒运动轨迹,利用欧拉双流体方法,引入颗粒群平衡计算模型(PBM),并通过编写用户自定义函数(UDF)引入颗粒湍流凝并、热凝并和增湿凝并核函数,计算颗粒凝并;指出光学法对颗粒凝并、破碎效果干扰较小,可以作为实验室观测颗粒凝并机理的有效检测手段。

Low-low temperature electrostatic precipitator（ESP）can effectively improve particle coagulation.On the basis of literature research and related research,this paper analyzes the mechanism of particle coagulation under low-low temperature working condition and gives a combined research methods between theoretical calculation and experimental observation.The method simulates turbulent flow field by 2d-LES model;calculates particle trajectories in the flue gas cooler by discrete phase model（DPM）;introduces particle group balance model（PBM）by Euler double fluid method;introduces kernel function of particle turbulence coagulation,heat coagulation and humidification coagulation and calculates particle coagulation by writing the user self-defined function（UDF）.It is pointed that the optical method causes small interference to particle coagulation and crushing effect,proved an effective detection method for laboratory observation of particle coagulation mechanism.