W. T. Kaune

Technique for estimating space‐charge densities in systems containing air ions

The exact analysis of electrified systems containing air ions is difficult because of the interdependence between the system electric‐field and space‐charge distributions. A technique is described in this paper for estimating space‐charge densities in unipolar and bipolar systems of air ions. A formula is introduced for systems containing only one ionic species which relates the space‐charge density at a point P to the space‐charge density at the ionic source and the transit time required for an ion to move from this source to P. In systems where air flow determines ionic velocities, transit times can be directly estimated. For other systems, a lower bound for the ionic transit time is derived and used to set an upper bound on the ionic space‐charge density. Two general results are derived for systems containing several species of ions during steady‐state zero‐wind conditions: the conversion of only a relatively few small ions into large ions, through collisions with condensation nucleii, results in drama...

Analysis of air ions in biological exposure systems, near HV dc electric power transmission lines, in rooms containing ion generators, and near exposed humans and animals

A number of systems containing space charge are analyzed using the transit‐time technique developed in an earlier paper. (1) An inequality is derived for a room containing an air‐ion generator which relates the ion source current to the minimum space‐charge density. (2) Published wind‐tunnel data are treated, and the characteristics of space‐charge plumes produced downstream from localized corona and radioactive sources are explained. (3) Space‐charge data published by other researchers can be evaluated; three examples are given, and in two of them published space‐charge densities substantially exceed calculated upper‐bound values. (4) Formulae are derived for the extrapolation of ground‐level space‐charge‐density, electric field, and ion‐current‐density data to points above ground level; these formulae are useful for characterizing the three‐dimensional environments in systems where only ground‐level measurements are available. (5) A simple upper bound is derived for ground‐level space‐charge densities p...