Reliable Estimation of Volumetric Heat Source in Numerical Simulation of Fusion Arc Welding Process

In recent times, the conduction heat transfer based numerical process models have been able to provide reliable quantitative understanding of the peak temperature, thermal cycle and weld bead dimensions in several fusion welding systems. However, the reliability of the computed results from these models depends significantly on the presumed dimensions of typical volumetric heat source that accounts for the arc heat input into the workpiece. We present here an analytical procedure to estimate the dimensions of the volumetric heat source as function of welding conditions and weld joint geometry in single and two-wire arc welding processes with electrode material deposition. The computed results of thermal cycle and weld bead dimensions are validated extensively with corresponding experimentally measured results from single wire gas metal arc welding and two-wire submerged arc welding processes.