Numerical Simulation For Electric Field,Flow Field And Particles Behavior In Electrostatic Precipitator

In recent years,the country has paid more and more attention to environmental issues,and the pressure on steel mills as high-polluting enterprises has doubled.Electrostatic precipitators are widely used by steel mills due to their high dust removal efficiency,stable operation and low cost.In steel mills,it is often used as a secondary dust removal device to purify low-concentration flue gas and capture particles with smaller diameters.The particle collection ability of electrostatic precipitator is closely related to the characteristics of electrostatic precipitator’s kneading electric field and flow field.However,under the influence of a strong electric field,it is extremely difficult to directly measure the flow of dust-containing gas and particle transport in the electrostatic precipitator.With the rapid development of computers,numerical simulation as a kind of low cost,can obtain more comprehensive information under various extreme conditions,etc.,has been more and more widely used.Due to the extensive development of numerical simulation technology,numerical simulation has become an effective tool for revealing the internal transmission behavior of electrostatic precipitators and realizing process optimization of electrostatic precipitators.In order to study the transport behavior of particles in the electrostatic precipitator in depth,this paper establishes a fully coupled model of dust charged motion based on Maxwell equations,continuity equations,momentum equations and Euler’s method,and uses the CFD open source software OpenFOAM to align the board.The charged transmission behavior of particles in the type electrostatic precipitator has been studied.Research indicates:(1)Particle charging has an effect of enhancing the electric potential in the electrostatic precipitator,but it will reduce the electric potential gradient and thus weaken the electric field intensity;the charged particles have a weakening effect on the charge density in the electrostatic precipitator;the charged particles have an effect on the electrostatic precipitator.The turbulence in the flow field has a great influence,it has a weakening effect on the symmetrical turbulence behind the first corona wire,and has a strengthening effect on the turbulence intensity on both sides of the dust collector;charged particles will reduce the dust collection rate of the electrostatic precipitator.(2)With the increase of particle size,the influence of charged particles on the electric potential,charge density,electric field force,flow field and dust collection efficiency in the electrostatic precipitator becomes weaker and weaker.(3)With the increase of the flue gas flow rate in the electrostatic precipitator,the degree of influence of the charged particles on the electric potential,charge density,electric field force,flow field and dust collection rate in the electrostatic precipitator will increase.(4)When the particle size is 1μm and the gas velocity is 0.5m/s,the one-way coupling dust collection efficiency is 94%,the two-way coupling dust collection efficiency is 80%,and the difference is 14%.The simulation results of one-way coupling and two-way coupling are quite different,two-way coupling is more accurate.(5)When the particle concentration is 1010m-3,the dust collection efficiency is 92%;when the particle concentration is 1012m-3,the dust collection efficiency is 80%.As the particle concentration increases,the dust removal performance of the electrostatic precipitator will be greatly reduced.