The Paton Welding Journal, 2025, №08

2025 №08 (04)

2025 №08 (06)

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The Paton Welding Journal, 2025, #8, 44-54 pages

Model of the anode boundary layer in welding arcs

I.V. Krivtsun¹, A.I. Momot^1,2, I.B. Denysenko^1,3, U. Reisgen⁴, O. Mokrov⁴, R. Sharma⁴

¹E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: momot.andriy@gmail.com
²Taras Shevchenko National University of Kyiv 64/13 Volodymyrs’ka Str., 01601, Kyiv, Ukraine,
³V.N. Karazin Kharkiv National University 4 Svobody Sq., 61022, Kharkiv, Ukraine
⁴Welding and Joining Institute, RWTH Aachen University 49 Pontstrasse, 52062, Germany

Abstract
A one-dimensional model of the anode boundary layer in atmospheric pressure electric arcs with refractory cathode and evaporating anode is proposed for two modes of the anode metal evaporation: diffusive and convective. The corresponding systems of differential and algebraic equations are formulated to compute the spatial distributions of the number densities and diffusive flux densities of electrons, ions, and atoms; the electron temperature and the heavy particle (atoms and ions) temperature; and the electric potential in the plasma of the anode layer. Additionally, the model allows to calculate the heat flux introduced by the arc into the anode. The boundary conditions for the differential equations of this model at the boundaries of the anode layer with the arc column plasma and the space-charge sheath are formulated. An approach for determining the plasma parameters at these boundaries is also proposed for each evaporation mode.
Keywords: anode boundary layer, welding arc, modelling, evaporating anode, metal vapor, diffusive evaporation, convective evaporation

Received: 12.05.2025
Received in revised form: 17.06.2025
Accepted: 24.07.2025

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Suggested Citation

I.V. Krivtsun, A.I. Momot, I.B. Denysenko, U. Reisgen, O. Mokrov, R. Sharma (2025) Model of the anode boundary layer in welding arcs. The Paton Welding J., 08, 44-54.

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