Numerical simulation of electrostatic field and its influence on submicron particle charging in small-sized charger for consideration of voltage polarity

Abstract In this paper, a pin-cylinder charger was employed to investigate the electrostatic field characteristic and its influence on submicron particle charging in positive and negative voltage polarity, respectively. The submicron particle's charging characteristics were also investigated thoroughly, including polarity, gas velocity, applied voltage, and injection position. Results showed that the increase of the applied voltage was proved a useful approach to enhance particle charging, especially for positive polarity. A 0.4 μm diameter particle achieved about a 60% increase from 5 kV to 8 kV. The negative polarity had advantages on particle charging, whose superiority could reach approximately 15% for 0.1 μm diameter particle in 8 kV voltage. The particle trajectory was a helpful bond to connect the particle charging with the electrostatic field, which decided the charging number and charging rate through the different distribution and intensity in two polarity conditions.