Computational analysis of arc phenomena during GTA welding with a constricted nozzle

Kyohei Konishi, Manabu Tanaka, Masaya Shigeta, Akihisa Murata, Tadasuke Murata, Anthony B. Murphy

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Gas Tungsten Arc (GTA) welding with a constricted nozzle is one of new higher-level welding processes. In this process, an arc plasma is strongly constricted due to a gas flow control using an additional gas nozzle which is called “constricted nozzle”. This welding process overcomes disadvantages of a conventional GTA welding such as low welding speed and low welding efficiency. As a result, it achieves a welding of butt joint of quite thin-sheet metals which is difficult for the conventional GTA welding. However the mechanism of this improvement is difficult to be understood by experimental approaches and is still unclear because the arc phenomena are quite complicated. In this study, we developed the computational model which uses a two-dimensional axisymmetric geometry in order to analyse the arc phenomena during the GTA welding with a constricted nozzle. The current density was concentrated to the center part of the arc plasma because the high speed gas which flows along the electrode cools the edge of arc plasma. As a result, the velocity of the plasma flow was greatly increased and the temperature of the arc plasma increased in the GTA welding with a constricted nozzle. Because of the arc constriction, the heat flux to the anode surface greatly increased at the center area. It was clarified that the constricted nozzle achieves the welding of butt joint of quite thin-sheet metals because it offers high energy density arc plasma by the arc constriction.

Original languageEnglish
Title of host publicationProceedings of CHT-17 ICHMT International Symposium on Advances in Computational Heat Transfer, 2017
PublisherBegell House Inc.
Pages2035-2040
Number of pages6
ISBN (Print)9781567004618
DOIs
Publication statusPublished - 2017
Externally publishedYes
EventInternational Symposium on Advances in Computational Heat Transfer, CHT 2017 - Napoli, Italy
Duration: 2017 May 282017 Jun 1

Publication series

NameInternational Symposium on Advances in Computational Heat Transfer
ISSN (Print)2578-5486

Conference

ConferenceInternational Symposium on Advances in Computational Heat Transfer, CHT 2017
Country/TerritoryItaly
CityNapoli
Period17/5/2817/6/1

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes
  • Mechanical Engineering
  • Condensed Matter Physics
  • Computer Science Applications

Fingerprint

Dive into the research topics of 'Computational analysis of arc phenomena during GTA welding with a constricted nozzle'. Together they form a unique fingerprint.

Cite this