Feasibility Study on Electrostatic Precipitator Combined with Ionic Fan for Air Purification in Lunar Module

Abstract

A unique electrostatic precipitator combined with an ionic fan is proposed for air purification in a lunar module, and its feasibility was investigated. Dust contaminating the air in the habitat module is circulated by the ionic wind generated by the ionic fan, which comprises coaxial cylinder electrodes. A positive direct current (DC) voltage exceeding the corona discharge onset voltage is applied to the inner electrode, where the sharpened edge faces the outer cylinder electrode. The migration of charged molecules generated by the corona discharge forms an air stream, and simultaneously, dust particles are charged. Charged particles are introduced into the electrostatic precipitator, which comprises parallel-plate electrodes. A high DC voltage less than the onset voltage of the spark discharge is applied to the electrodes, and the introduced charged dust particles are trapped in the collection electrodes owing to the Coulomb force. It appears that dust is effectively cleaned by a compact system. An ozone filter is installed to decompose the ozone synthesized in the corona discharge field. Because the proposed system affords simplicity, a small configuration without mechanical moving components, lightweight, low power consumption, and silence, it is suitable for use in the lunar habitat module and pressurized rover. The proposed air-purification system would contribute to reduce the load on the mechanical filtration system.