Study On The Migration And Settlement Of Charged Particles In The Electric Field Of Porous Dust Collecting Electrodes

At present,electrostatic precipitators still play an important role in the field of smoke and dust purification,but in the face of more stringent ultra-low emission standards,electrostatic precipitators urgently need to further improve the collection efficiency of fine particles in the power industry or non-electric industries.For this reason,based on the influence of the electric wind effect on the movement state of fine particles and slowing down the turbulence near the dust collecting electrode,a porous dust collecting electrode electrostatic precipitator is proposed.The characteristic structure of the electrode is that the dust collecting electrode is a porous plate type.In order to analyze the migration and sedimentation laws of the charged particles in the new type of electrostatic precipitator,and to guide the selection and design of the new type of electrostatic precipitator,the following research was mainly carried out.The paper uses computational fluid dynamics research methods,with the help of finite element numerical simulation software COMSOL Multiphysics,uses its electrostatic module,dilute substance transfer module,fluid mechanics module and particle tracking module to build a description of the migration and sedimentation of charged particles in the electrostatic precipitator The numerical model of the process,and the numerical reliability and accuracy of the numerical model were verified by the classical experimental data in the literature,and the research method of the paper was determined.Based on the numerical simulation analysis of the gas ionization,particle charging,charged particle migration and sedimentation process of the porous dust collecting electrode electrostatic precipitator,the mechanism of the porous dust collecting electrode electrostatic precipitator improving the trapping of fine particles is revealed.The numerical simulation results were analyzed through orthogonal experiments,and the influence degree and influence law of the applied voltage,wind speed of the electric field,dust particle size and perforated plate opening rate on the effective driving speed were obtained.The main results of the paper are as follows:(1)The calculated value of the gas-solid two-phase flow model of the electrostatic precipitator in the paper is in good agreement with the classical experimental value,which verifies the reliability and accuracy of the numerical model of the paper.(2)Based on the traditional wire-plate type electrostatic precipitator,combined with the numerical simulation analysis of the gas ionization,particle charging,charged particle migration and sedimentation process of the porous dust collecting electrode electrostatic precipitator,it is concluded that the opening of the dust collecting electrode has almost no effect The space charge density and electric field intensity in the area between the wires and plates will significantly affect the electric field intensity near the porous plate.The round holes have almost no effect on the charge amount and charging process of the particles.The porous plate structure weakens the airflow to the dust collection area.The scouring action and the particles entering the cavity of the porous plate finally settle in the cavity so that the porous plate electrode structure can effectively increase the effective driving speed of the 0.1?m～5?m fine particles.(3)Based on the orthogonal experiment,25 sets of numerical simulations were carried out.After analyzing the results,the order of the influence of the 4 factors discussed in this article on the effective driving rate within the experimental level is: perforated plate opening rate,applied voltage,particle size And the wind speed of the electric field.