NUMERICAL-SIMULATION OF THE ARC PRESSURE IN GAS TUNGSTEN ARC-WELDING

A two-dimensional axisymmetric numerical model has been developed to d escribe the heat transfer and fluid flow in the gas tungsten welding a re. The electrode-tip geometry is considered in the model and the cath ode and are column regions are included in the solution of the current continuity equation. The magneto-hydrodynamics equations are solved u sing the SIMPLE algorithm. The prediction of the are column temperatur es is in fair agreement with experimental results; moreover, the compu ted results indicate that the distributions of are parameters such as current density, electromagnetic force and velocities, reflect well th e generating mechanism of the are pressure. In addition, the effects o f the current, the electrode-tip angle and the are length on the are p ressure distribution are analyzed by the use of the are model that has been developed.