摘要
文章基于商业计算流体力学(CFD)软件,对某低低温电除尘系统进行了多场条件下的数值模拟。采用k-ε模型来模拟湍流场,用离散相模型(DPM)来模拟飞灰颗粒的运动,用换热器模型和多孔跳跃模型模拟烟冷器内温度场,用电磁流体模型(MHD)模拟电场,用颗粒群平衡模型(PBM)模拟颗粒团聚规律。结果表明:烟道内布置导流板及阻流板后,电除尘器各分室进口流量偏差均在±1%以内,出口不超过±0.5%。颗粒相质量流量分配偏差也均未超过±5%。各室入口截面烟气流速相对均方根差均不超过0.25。模拟烟冷器内各截面的温度、密度及流速变化规律与实际相符。电场内电势分布由放电极向收尘极呈不均等环状分布,粒径越大的颗粒越容易被收集,小颗粒易发生逃逸。随着时间的推移,烟冷器内颗粒平均粒径逐渐增大,当t=0.8 s以后,颗粒平均粒径趋于平稳。
Based on commercial CFD software, the numerical simulation study of low-low temperature electrostatic precipitator(ESP) system was carried out on multi-field conditions. In simulation process, the flow field was simulated with k-εturbulence model, particle trajectory was simulated with discrete phase model(DPM) model, temperature field in flue gas cooler was simulated with jumping and porous heat exchanger model, electric field was simulated with electrical resistivity model(MHD), particle aggregation was simulated with particle group balance model(PBM). The numerical simulation results show that, with guide plate and choke plate, flow deviation of ESP chamber inlet is within ±1%, outlet flow deviation is within±0.5%, far better than the standard requirements. The distribution deviation of particle phase mass flow is within ±5%. The root mean square error of gas flow velocity on the ESP inlet section is no more than 0.25. The changes of temperature, density and velocity of each section in the flue gas cooler are in accordance with the reality. The distribution of electric potential in the electric field is distributed by the discharge electrode to the dust electrode, the larger the particle size is, the more likely it is to be collected in the electric field, and the smaller particle size is more likely to escape. The particle size gradually increased with time, the average particle size of particles tended to be stable at t=0.8 s.
作者
温刚
刘含笑
周林海
陈招妹
冯国华
WEN Gang;LIU Hanxiao;ZHOU Linhai;CHEN Zhaomei;FENG Guohua(State Grid Xinjiang Electric Power Co., Ltd, Urumqi 830001. China;Zhejiang Feida Environmental Science & Technology Co., Ltd., Shaoxing 311800, China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2019年第4期180-187,共8页
Environmental Science & Technology
基金
国家重点研发计划(2017YFB0603202)
国家重点研发计划(2016YFC0203704)
关键词
低低温电除尘器
CFD
多相流
气流分布
多物理场
low-low temperature ESP
CFD
multiphase flow
air flow distribution
multi-physics field
