电除尘器流场、颗粒场及电场的数值模拟研究

Numerical Simulation of Flow Field,Particle Field and Electric Field for ESP

通过计算流体力学(computational fluid dynamics,CFD)软件FLUENT,基于k-ε湍流模型、离散相模型(discretephasemodel,DPM)、电磁流体(magnetohydro dynamics,MHD)模型等对1 000 MW机组电除尘器进行多相流及多场条件下的数值模拟研究。结果表明:布置烟道导流板及进口封头气流分布板后,电除尘器(electrostaticprecipitator,ESP)各进口烟道内烟气流量、颗粒相流量及第1电场进口截面的速度均匀性均得到明显改善,各进口烟道内烟气流量偏差均在±1%以内,各室入口截面烟气流速相对均方根差均不超过0.25,优于标准要求。通过计算不同供电电压及入口流速时模型的除尘效率可知:电除尘效率与供电电压正相关,与入口流速负相关,计算规律与实际相符。

Based on computational fluid dynamics software,with k-εturbulence model,discrete phase model(DPM)and magneto hydro dynamics(MHD)model,the numerical simulation study of electrostatic precipitator(ESP)system was carried out on multi-field conditions.The numerical simulation results show that,with guide plate and distribution plate,flow deviation of ESP chamber inlet,particle phase flow rate and the first electric field entrance section were improved significantly.Flow deviation of ESP chamber inlet is within±1%,the root mean square error of gas flow velocity on the ESP inlet section is no more than 0.25.The dedusting efficiency of the model which was calculated at different power supply voltages and inlet flow rates show that,the efficiency of electric dust removal is positively correlated with the supply voltage and negatively correlated with the inlet velocity,which agrees with the reality.