DIFFUSION CHARGING OF ATMOSPHERIC DROPLETS BY IONS, AND THE RESULTING COMBINATION COEFFICIENTS

Abstract

The role of ionic diffusion in electrically charging drops in the atmosphere is investigated. Space charge and chemical adsorption being neglected, exact expressions are obtained for the charging rate and the average equilibrium charge acquired by a drop in an ionized atmosphere. The augmentation of the charge by appreciable relative motion is determined. The combination coefficients for neutral and charged droplets are calculated and found to agree with direct measurements. It is concluded that ionic diffusion plays a vital role in determining the electrical equilibrium in the atmosphere.