Two-way coupling simulation for electric field， flow field and particle behaviors in an electrostatic precipitator

To study the electrical characteristics and particle transport behaviors of a wire-plate electrostatic precipitator， the open-source software OpenFOAM was applied to solve the Maxwell equations， continuity equations， momentum equations， particle charge-motion equations， and to investigate the effects of charged particles in the cases of different particle concentrations on the electric field， flow field， and particle behaviors in the electrostatic precipitator. The numerical results showed that the spatial charge effect of particles broke the law of symmetrical distribution of electric field strength， ionic charge density， and electric field force， and the greater the particle concentration， the stronger the asymmetry of the electric field. When the particle concentration increased from 0 mg/m3 to 500 mg/m3， the electric field intensity near the corona wire decreased from 1.4×106 V/m to 1.31×106 V/m， and the electric field intensity near the grounded plate toward the first corona wire increased from 7.5×105 V/m to 8.7×105 V/m. The ionic charge density decreased with the increase in particle concentration. The increase in particle concentration led to a decrease in the electric field force near the corona wire and an increase in the electric field force near the plate， which had a promoting effect on the velocity of the air along the main flow direction. The increase in particle concentration also led to the phenomenon that the particle trajectories in the electrostatic precipitator shifted to the central axis. The movement of small particles was significantly affected by turbulent flow， and the trajectories of particles less than 5 µm bifurcated obviously in the case of turbulent flow.