Accession Number : AD0668510

Title :   EXPERIMENTAL STUDY OF A TRANSPIRATION-COOLED, CONSTRICTED ARC.

Descriptive Note : Interim rept. Apr 65-Jun 67,

Corporate Author : MINNESOTA UNIV MINNEAPOLIS HEAT TRANSFER LAB

Personal Author(s) : Bruber,G. G. ; Pfender,E. ; Eckert,E. R. G.

Report Date : FEB 1968

Pagination or Media Count : 114

Abstract : Experimental work with a transpiration-cooled arc is described. An apparatus was developed which verifies the analytical prediction that an electric arc can be confined and constricted by an entirely transpiration-cooled wall. The arc was operated in argon atmosphere with currents ranging from 35 to 160 A. A porous ceramic (ALSIMAG 447) tube was used as constrictor material. The investigations encompass basic trends of the arc, the constrictor performance, and the flow behavior with their mutual interactions. By introducing some simplifying assumptions, a number of formulae, containing observable quantities were derived which are useful for the representation of experimental results and which facilitate their comparison with analytical studies. Three different types of arc characteristics are plotted and used for a description of the transpiration-cooled arc. Results of spectrometric temperature measurements in the arc jet using the 5 mm ID constrictor tube are also included. Details of an improved transpiration-cooled arc arrangement based on previous experience, are described and some preliminary results obtained with this apparatus are reported. (Author)

Descriptors :   (*PLASMA GENERATORS, COOLING), (*ELECTRIC ARCS, PLASMA GENERATORS), EVAPOTRANSPIRATION, HEAT FLUX, POROUS MATERIALS, MATHEMATICAL MODELS, PRESSURE, DISTRIBUTION, ARGON, CERAMIC MATERIALS, PERFORMANCE(ENGINEERING), PLASMA JETS

Subject Categories : Electricity and Magnetism
      Plasma Physics and Magnetohydrodynamics
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE