Study of magnetically enhanced corona pre-charger

• Published in: Journal of electrostatics Vol. 65; no. 2; pp. 101 - 106
• Main Authors: Xu, Dexuan, Sheng, Lianxi, Wang, Haijun, Sun, Yinghao, Zhang, Xiaoyu, Mi, Junfeng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2007
• Subjects: Capturing fine aerosol particles; Charging aerosol particles; Magnetically enhanced corona discharge; Pre-charger; Pre-charger; Capturing fine aerosol particles; Magnetically enhanced corona discharge; Charging aerosol particles
• ISSN: 0304-3886; 1873-5738
• DOI: 10.1016/j.elstat.2006.07.007

In this paper, experimental investigations of the discharge characteristics of magnetically enhanced corona discharges, for the purpose of capturing fine aerosol particles, are presented. The discharge mechanism during such a process is analyzed as well. The effects of magnetic enhancement under different magnet flux densities, and in positive- or negative-corona discharges, were experimentally compared. The magnetically enhanced effects in different inter-electrode regions were studied. Experimental results demonstrated that the magnetic field could efficiently increase the concentrations of both the negative ions and the free electrons during negative-corona discharge. The dominant mechanism of magnetic enhancement in a corona discharge involves the Larmor precessions of free electrons which enhance ionization of the gas molecules near the discharge electrode. A convenient configuration for enhancing corona discharge was formed by placing permanent magnets with a local strong magnetic field near the discharge electrode. A magnetically enhanced negative-corona (MNC) pre-charger was assembled in front of an electrostatic enhancement filter. The influence of the MNC pre-charger on the efficiencies of an electrostatic enhancement filter was measured and compared with that of a conventional corona pre-charger. The free-electron-charging mechanism of the MNC pre-charger was preliminarily analyzed. Our results show that the new pre-charging technique is promising for capturing fine aerosol particles in electrostatic enhancement filters or electrostatic precipitators.