Ion-Flow Models: A Review

Modeling a unipolar ion flow is a difficult task that has been shared by a number of researchers in the past century. This chapter is presented as a cursory survey of the available studies on the unipolar ion flow. Deutsch established three hypotheses, some of which are applicable under specialized conditions, regarding the unipolar ion flow in the wire-plane gap. The chapter describes some unipolar flow field problems before discussing special models namely, drift of charged spherical clouds and a method based on a simple geometrical construction describing the asymptotic ion flow for a rod-plane configuration. Estimating the Deutsch hypothesis (DH) validity is an exercise still under way and that the involved investigations persist to contradict each other.