Numerical Analysis of Oxygen Mass Transfer in Two-TIG Arc

doi:10.3901/JME.2021.04.053

Abstract

Abstract: A three dimensional(3D) mathematical model of oxygen transfer for two-tungsten inert gas (TIG) arc is developed and the oxygen mass fraction for different ratios of the electrode current is investigated. It is shown that the oxygen mass fraction distribution is quite heterogeneous, and the ratios of the two electrodes current for an equal total current has significant role on the oxygen distribution. The oxygen mixed from the torch with lower current is transported more to the periphery of the arc, provided that the electrode current is different; while the oxygen mixed from one torch is transported more to the central region of the arc, presenting higher oxygen concentration, if the electrode current is equal. As a whole, the oxygen is concentrated remarkably to the side of the arc from which it is introduced. At the position 0.1 mm above the anode, the distribution of the oxygen is non-uniform as well. As the current is different for each electrode, the oxygen mass fraction and number flux are lower than those for equal current of the electrode, predicting reduced oxygen dissolved into the weld pool in this case.

Key words: two TIG, oxygen, mass transfer, numerical analysis, current partation

CLC Number:

TG156

WANG Xinxin, CHI Luxin, XU Huibin, FAN Ding. Numerical Analysis of Oxygen Mass Transfer in Two-TIG Arc[J]. Journal of Mechanical Engineering, 2021, 57(4): 53-62.

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