Characteristics Simulation And Experimental Study Of Negative Corona Discharge

The expression of microphysical process has not yet been investigated clearly as the complexity of negative corona discharge at atmospheric pressure,and the characteristics are closely related to the discharge space and shape of the electrode.This paper improves the corona discharge of the traditional mathematical model.Multi physical fields are calculated and studied quantitatively in the corona discharge under different environmental conditions,as well as Trichel pulse waveform characteristics itself.The main contents of this paper are shown as follows.(1)The shortcomings of the traditional discharge model are found by summarizing the previous studies.The transfer and diffusion model of charged particles has been improved using fluid dynamics equation and Poisson equation.The effect of various parameters on the discharge is added.In addition,the Helmholtz equations are coupled with the photoionization term in partial differential equations.Therefore,the traditional mathematical model has been improved.(2)The microscopic physical characteristics of negative corona discharge are calculated by the finite element simulation algorithm.The photoionization term is solved by Helmholtz equations.The influences of photoionization are compared on the Trichel pulse waveform,it is found that the photoelectron-ion pair produced by photoionization will weaken the peak value of the first pulse indirectly.(3)The influences of pressure,temperature and humidity parameters of the Trichel pulse characteristics and photoionization using improved mathematical model are studied.The 'variation of the peak characteristic of Trichel pulse with the environmental parameters is also analyzed.(4)Due to the strong periodicity of the Trichel pulse,the double exponential function fitting was utilized to study the variation of parameters of different double exponential equations.Due to the domination of the effect of the applied voltage and radius of curvature of the electrode on Trichel pulse,two models were utilized to analyze the effect of photoionization in this section.(5)An improved hybrid numerical algorithm was utilized to simulate the charging properties and trajectory of the particles in an electrostatic precipitator.The corona discharge,migration and charging progress of particles were investigated in different conditions.The error of the traditional model can be reduced relatively and several conclusions can be given that the trajectory of the particles is different when considering corona or not.