1999 Volume 14 Issue 1 Pages 46-54
Many studies on particle charging theory in submicron region were reported previously, however, experimental studies on particle charging were only a few. Therefore, in this study, monodisperse Polystyrene latex (hereafter, PSL) aerosol (particle diameter, Dp = 0.401, 0.791, 1.001 μm) and polydisperse Dioctylphthalate (hereafter, DOP) aerosol (Dp = 0.8 μm) were charged by a corona type particle charger, which were charged by positive ions, and then, the amount of charge was measured by two kinds of methods; a differential mobility analyzer (hereafter, DMA) and electrical aerosol detector with an induced type Faraday cage (hereafter, EAD). In the present experiment, charging characteristics of particle, that is, the relation between number of charges on particle ions and charging time, was investigated with parameters which were particle diameter, ion concentration and strength of electric field. An extensive experiment in electric field was carried out by changing frequency of square wave of applied voltage and particle diameter on PSL. The experimental results were compared with the combined field and diffusion charging theory in the continuum region, that is, Liu-Kapadia's theory. It was found that the experimental results were agreed with the theory.
