Authors: C. Winkler, G. Amberg
Addresses: Department of Mechanics, KTH, Stockholm S-100 44, Sweden. ' Department of Mechanics, KTH, Stockholm S-100 44, Sweden
Abstract: A mathematical model simulating multicomponent, surfactant mass transfer in the liquid region arising in the specimen directly beneath the electrode during GTA-welding is developed. The sorption controlled surfactant mass transfer is due to convection and diffusion in the surface and bulk liquid regions. Interaction coefficients and multicomponent Langmuir adsorption isotherms are used to consider the interaction between the several surfactants involved. The model is added to a mathematical formulation that is often used for GTA-welding, and is finally used to calculate the fluid and heat flow and surfactant distributions in the weld pool. In the simulations, GTA-welding on stainless steel plates for a ternary Fe-S-O system is considered for varying surfactant concentrations and for varying heat input conditions. A very good agreement between numerically obtained and corresponding experimental weld pool shapes is found. Thus, it is shown that previous shortcomings in modelling of GTA-welding can be overcome if multicomponent surfactant mass transfer is considered.
Keywords: GTAW; gas tungsten arc welding; simulation; melt flow; thermocapillary; surfactant mass transfer; fluid flow; heat transfer; surfactant distributions; weld pool; stainless steel plates; spot welding.
Progress in Computational Fluid Dynamics, An International Journal, 2005 Vol.5 No.3/4/5, pp.190 - 206
Published online: 05 Apr 2005 *Full-text access for editors Access for subscribers Purchase this article Comment on this article