Evaluation of the heat flow from plasma to the end of an aluminium wire–anode

Abstract

Investigations were carried out to develop a method of determining the density of the heat flow from plasma to the surface of a wire–anode depending on the wire feed rate, the thickness of the molten metal film at the end surface and the angle between the axis of the wire and the molten metal surface. It is taken into account that the heat flow, arriving from plasma to the end of the wire, is used to change the enthalpy of the metal not only in the solid but also liquid state. It is shown that the mean mass temperature of heating the metal film is 2/3 of the change of temperature in the height of the film. In the conditions investigated in these experiments, the superheating of the metal film above the melting point was 283 K. The surface temperature of molten aluminium was considerably lower than the boiling point so that the evaporation of metal was ignored when calculating heating of the wire.

Keywords:

• Gas-discharged plasma
• heat flux density
• metal enthalpy
• transient heating
• film heating average temperature
• constant flow rate equation

Notes

Selected from Svarochnoe Proizvodstvo, 2015, 68 (10) 7–11.