Automatic Welding, 2016, №11



2016 №11 (07)

DOI of Article 10.15407/as2016.11.01

2016 №11 (02)

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Avtomaticheskaya Svarka (Automatic Welding), #11, 2016, pp. 3-10
 

Numerical analysis of plasma characteristics of constricted and free-burning arc with a refractory cathode

I.V. Krivtsun¹, I.V. Krikent² and V.F. Demchenko¹

¹E.O. Paton Electric Welding Institute, NASU 11 Kazimir Malevich Str., 03680, Kiev, Ukraine. E-mail: office@paton.kiev.ua
²Dnieprodzerzhinsk State Technical University 2 Dnieprostrojevskaya Str., 51918, Dnieprodzerzhinsk, Ukraine
 
 
Abstract
Self-consistent mathematical model of the processes of energy-, mass- and electric transfer in the column and anode region of the electric arc with refractory cathode was used as a basis to perform numerical analysis of thermal, electromagnetic and gas-dynamic characteristics of arc plasma for constricted (plasma) and free-burning argon arc with copper water-cooled anode. Results of calculation of characteristics of arc column plasma show that distributions of electric current density, temperature and velocity of constricted arc plasma can greatly differ from the respective distributions for free-burning arc, depending on arc current, plasmatron nozzle channel diameter and plasma gas flow rate. Characteristics of near-anode layer of plasma arc also differ significantly from the respective characteristics of free-burning arc, depending on the above arcing mode parameters. Thus, by varying arc current, plasmatron nozzle channel diameter and plasma gas flow rate, it is possible to effectively control the characteristics of thermal, electromagnetic and, particularly, dynamic impact of the constricted arc on anode metal surface. 13 Ref., 1 Table, 10 Figures.
 
Keywords: constricted (plasma) arc, free-burning arc, refractory cathode, water-cooled anode, arc column, anode region, arc plasma characteristics, mathematical modeling
 
 
Received:                04.10.16
Published:               14.12.16
 
 
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