电场、流场耦合作用下脱除细颗粒物的实验和数值模拟  

Experiments and Numerical Simulations of the Removal of Fine Particles in the Coupling Field of Electrostatic Precipitators

作　　者：周栋梁[1] 李水清[1] 靳星[1] 熊桂龙[1] 黄炜 

机构地区：[1]清华大学热科学与动力工程教育部重点实验室,北京市海淀区100084 [2]福建龙净环保股份有限公司,福建省龙岩市364000

出　　处：《中国电机工程学报》2016年第2期453-458,共6页Proceedings of the CSEE

基　　金：国家高技术研究发展计划项目(863计划)(2013AA 065004);国家重点基础研究发展计划项目(973计划)(2013CB228506)~~

摘　　要：细颗粒物在电、流场耦合作用下的捕获不但是电厂尾部除尘系统的核心问题,也是空间环境内灰尘限制动力或光学元件性能的关键。以电除尘器为研究对象,通过实验和数值模拟研究了细颗粒物在电、流场耦合作用下的迁移、捕获机理。实验结果表明0.1~1μm的颗粒存在穿透窗口;在电除尘器内粉尘浓度随停留时间的变化并不成比例,而是在停留时间为1.5~2 s左右存在一个较为明显的高效脱除区域,继续增加停留时间对于0.1~3μm颗粒的脱除效率的影响并不明显。通过数值模拟研究了电除尘器内的电势与电场强度分布及其脱除效率,模拟结果表明在计算1μm以下颗粒脱除效率的过程中,对曳力考虑Cunningham滑移修正后的模拟结果与实验结果较为一致,Cunningham滑移修正对于模拟计算亚微米颗粒脱除效率十分重要。The capture of fine particles in the coupling of electric field and flow field is not only an essential problem for the power plant dust removal system, but also a key issue for power components and optical components in the aerospace environment. Through experiments and numerical simulations of electrostatic precipitators（ESP）, the transport and capture characteristics of fine particles in the coupling electric field and flow field were investigated. The results show that there is a penetration window in the 0.1-1 μm size range. The change of dust concentrations is not proportional to the residence time, and there is a high-efficiency region where the residence time is about 1.5-2 s. After that, the influence of residence time is not obvious for particles in the 0.1-3 μm range. The potential distribution, electric field intensity and collection efficiencies were obtained by numerical simulations. With the Cunningham slip correction of drag forces, the simulated collection efficiencies are consistent with the experiment results for particles smaller than 1μm. The Cunningham slip correction is important for the simulation of collection efficiencies for sub-micrometer particles.

关 键 词：细颗粒物 电除尘器 颗粒脱除 电流场耦合 

分 类 号：TK121[动力工程及工程热物理—工程热物理]