A computer analysis for the determination of electrode voltage losses in magnetohydrodynamic-generator plasmas.

Abstract

This work investigates the nature and extent of the voltage drops in the vicinity of MHD non-emitting electrodes, especially losses attributable to the sheath. The non-existence of a one-dimensional sheath solution is proved and a computer model with two-dimensional, periodic active sites representing a flat plate electrode is developed. The sheath and ambipolar regions evolve from the same set of equations in a self-consistent way, obviating the requirement to match boundary conditions between the regions. With this model the effects of a magnetic field and Joule heating are studied. Results are compared with experimental observations. To supplement the sheath investigation a peripheral study of the boundary layer voltage losses has been made and a relatively simple technique for determining these losses are presented.