Accession Number : AD0636160

Title :   AN ANALYTICAL STUDY OF THE PHYSICAL PROCESSES IN THE CATHODE REGION OF AN ARC.

Descriptive Note : Final rept., Feb 62-Jun 65.

Corporate Author : GENERAL ELECTRIC CO PHILADELPHIA PA MISSILE AND SPACE DIV

Personal Author(s) : Lee, T. H. ; Greenwood,Allan ; breingan,W. D. ; Fullerton,H. P.

Report Date : APR 1966

Pagination or Media Count : 127

Abstract : The objective of the work was to study the fundamental operating processes in the cathode region of an electric arc. The study was primarily theoretical, supplemented with some experimental observations, particularly for arcs in a flow field. A model for the arc between the cathode and the plasma proper was formulated. The governing equations for the different regions of the model were derived and solved numerically by a digital computer. Boundaries between regions were matched as far as possible, to give a self-consistent solution. The solutions obtained indicate that using the model, it is possible to explain electron emission, cathode drop, energy balance, ion current flow and ionization in the transition region for an arc on a refractory cathode in an argon gas. It was thought important to see how the cathode region joins to the contracted portion of the plasma. The energy balance in the contracted region was also studied by treating it as a multicomponent gas with the possibility of its not being in thermal equilibrium. The solution for this region indicates that when flow is an important factor in the energy balance at the arc boundary, there could be a considerable difference between the electron and ion temperatures at the arc boundary. It is believed that this effect must be considered in any study in the entrance region of arc plasma heaters. (Author)

Descriptors :   (*ARC HEATERS, *PLASMAS(PHYSICS)), (*ELECTRIC ARCS, PLASMAS(PHYSICS)), (*CATHODES, ELECTRIC ARCS), GAS FLOW, WIND TUNNELS, MATHEMATICAL MODELS, EMISSIVITY, THERMODYNAMICS, ARGON, TRANSPORT PROPERTIES

Subject Categories : Test Facilities, Equipment and Methods
      Electricity and Magnetism
      Plasma Physics and Magnetohydrodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE