ELECTRICAL CONDUCTION FROM A LAMINAR ARC HEATED FLOW TO A COOLED CYLINDRICAL ANODE.

Abstract

An investigation was made of the electrical conduction in an arc heated atmospheric pressure plasma flow passing through a ring anode. The arc plasma flow is maintained in a tube between an upstream cathode and an anode at the tube exit. A 'test' ring anode upstream of the primary anode is biased relative to its floating potential permitting current to be drawn to the flowing plasma. Anode characteristics were measured for helium and argon in a one centimeter duct at atmospheric pressure. Experiments have included copper, nickel, molybdenum, silver, magnesium, tungsten, aluminum, and iron as anode materials. Electrical conduction to the anode is found to be a function of arc gas type, main arc current, anode material, and anode geometry for a fully developed flow in a fixed tube size. Electrical conduction is strongly dependent upon the cleanliness of the apparatus. At low bias currents, electrical conduction tends to be uniformly distributed over the anode surface in the circumferential direction. At higher levels of bias current, non-uniform electrical conduction distributed over a small surface area ('anode spots') usually occurs. A theory was developed for conduction in helium for low bias currents. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1967
Accession Number
AD0660571

Entities

People

  • P. W. Runstadler Jr.

Organizations

  • Dartmouth College

Tags

DTIC Thesaurus Topics

  • Aluminum
  • Barometric Pressure
  • Elements
  • Geometry
  • Group 6 Elements
  • Magnesium
  • Materials
  • Metals
  • Molybdenum
  • Refractory Metals
  • Transition Metals
  • Tungsten

Fields of Study

  • Physics

Readers

  • Plasma Physics.