To reveal the influence of forced convection on gas shielded arc welding temperature field, the infrared camera was used to investigate the temperature field of the base metal in CO2 arc welding.

In forced convection the movement of the fluid or gas is caused by an external agent which gives rise to pressure differences.

If there is a bulk mixing of the layers of gas in the tube by mechanical stirring or because of a density gradient, mass transfer occurs primarily by the mechanism of forced or natural convection.