Analysis of volumetric radiation heat flux and experimental comparison with arc light sensing in GTA welding process

The volumetric radiation heat flux was analyzed from a model of the entire free burning arc of GTA welding and its results were compared with measurements of the arc light intensity to find a relationship between them. Experiments were carried out for various welding currents using electrodes of different vertex angles. The results showed similar behavior for both the volumetric radiation heat flux and the light intensity of GTA welding arc. Both presented a linear relationship with the logarithmic value of the arc length. Consequently the arc light intensity could be assumed to have a linear relationship to its radiation heat in the range of normal arc length.