Simultaneous measurements of wire electrode surface contamination and corona discharge characteristics in an air-cleaning electrostatic precipitator

Contamination of the corona wire in a wire-to-plate type air-cleaning electrostatic precipitator is studied experimentally. In order to enhance the contamination of wire, air containing dust is directly supplied to a part of the wire electrode. Spores of Lycopodium and cigarette smoke particles are used as test dusts. Simultaneous measurements of wire electrode optical images and corona discharge modes are carried out during contamination processes. Results show that corona discharge modes and optical emission from the wire electrode change with time due to the surface contamination, in the case of cigarette smoke, after a time elapsed, streamer coronas appear due to the buildup of smoke particles on the wire surface. After the first streamer generation, the corona current fluctuates with time because the formation and diminution of the projections occur alternately at the different parts on the wire electrode surface.