Particle charger with sheath air flow for enhancing charging efficiency

Abstract

A particle charger with sheath air flow for enhancing charging efficiency includes a housing and a discharge wire. The housing has a charging chamber for accommodating the discharge wire, a particle inlet, a sheath air inlet, an outlet and an accelerating channel. A clean sheath air is guided through the sheath air inlet into the charging chamber to surround charged particles, reducing deposition of charged particles on the inside wall of the housing. A relatively small annular gap of accelerating channel accelerates the charged particles to exit the particle charger, and therefore minimized the particle electrostatic loss due to depositing on the inner surface of the housing. Additionally, uncharged particles approach the discharge wire axially, and charged particles move away radially. It is helpful for the charged particles to diffuse rapidly and uniformly, thereby enhancing the charging efficiency.