Heat transfer and fluid flow in a partially or fully penetrated weld pool in gas tungsten arc welding

In this study, fluid flow driven by a combination of electromagnetic force, buoyancy force, are drag force, and surface tension gradient is numericall y analyzed for a partially or fully penetrated weld pool in stationary gas tungsten are welding (GTAW). Irregular shape of the weld pool and the movin g liquid-solid interface is handled by a boundary-fitted-coordinates techni que. Surface tension on the top and the bottom free surfaces of the weld po ol is found to play a critical role in determining the flow pattern in the weld pool. The calculated GTA weld bead geometry compares favorably with ex perimental results. (C) 2000 Elsevier Science Ltd. All rights reserved.