Operating characteristics and energy distribution in transferred plasma arc systems

Journal Article · Wed Dec 01 04:00:00 EST 1982 · Plasma Chem. Plasma Process.; (United States)

DOI:https://doi.org/10.1007/BF00567563· OSTI ID:7156536

Choi, H K; Gauvin, W H

A specially designed plasma chamber was constructed to study the operating characteristics of a dc plasma-transferred arc of argon, struck between a fluid convective cathode and a water-cooled anode. The arc voltage increased markedly with arc length and with an increase in the inlet velocity of the argon flow past the cathode tip, and much less with an increase in current. Radiation from the plasma column to the chamber walls and transfer of energy to the anode were the two principal modes of transfer of the arc energy. The former was dominant in the case of long arcs and at high inlet argon velocities. At the anode, the major contribution was from electron transfer, which occurred on a very small area of the anode ( about5 mm in diameter). Convective heat transfer from the plasma was somewhat less. In all cases, the arc energy contributions to cathode cooling and to the exit gas enthalpy were small. From total heat flux and radiative heat transfer measurements, it was estimated that the plasma temperature just above the anode was in the range 10,000-12,000 K. Preliminary experiments with an anode consisting of molten copper showed that the arc root was no longer fixed but moved around continuously. The arc was othwewise quite stable, and its operating characteristics differed little from those reported for solid anodes, in spite of the greater extent of metal vaporization.

• Research Organization: McGill Univ., Montreal, Quebec
• OSTI ID: 7156536
• Journal Information: Plasma Chem. Plasma Process.; (United States), Journal Name: Plasma Chem. Plasma Process.; (United States) Vol. 2:4; ISSN PCPPD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101* -- Metals & Alloys-- Preparation & Fabrication
ARGON
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTORS
COPPER
CURRENTS
DEPOSITION
DESIGN
DIRECT CURRENT
ELECTRIC ARCS
ELECTRIC CURRENTS
ELECTRIC DISCHARGES
ELECTRODES
ELECTRON TRANSFER
ELEMENTS
ENERGY SPECTRA
ENERGY TRANSFER
FLUIDS
GASES
HEAT TRANSFER
METALS
NITROGEN
NONMETALS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PLASMA
PLASMA ARC SPRAYING
QUENCHING
RARE GASES
SPECTRA
SPRAY COATING
SURFACE COATING
TRANSITION ELEMENTS
ULTRAHIGH TEMPERATURE