Abstract
Abstract
Double-sided arc welding powered by a single power supply is a new type of welding process developed recently at the University of Kentucky. Experiments show that this process has advantages over conventional single-sided arc welding in enhancing penetration, minimizing distortion, improving solidification structure and welding aluminium without the necessity of using filler metal for cracking prevention. In this paper, a three-dimensional transient numerical model is developed for the heat transfer and fluid flow in double-sided gas-tungsten arc welding, including flat-position welding and vertical-up position welding. Based on a non-uniform staggered grid system, the governing equations are solved numerically using the SIMPLEC algorithm. The roles of the surface tension gradient, electromagnetic force and buoyancy force in determining the fluid flow and weld penetration are analysed and compared with those in the conventional arc welding process. The computed weld geometry is compared with experimental results and it is found that the computational results agree with the experimental results with reasonable accuracy.