Three-dimensional modeling of turbulent weld pool convection in GTAW processes

Abstract

Three-dimensional turbulent weld pool convection in a gas tungsten are welding (GTAW) pool is simulated using a high Reynolds number k–ϵ model. The k–ϵ model is suitably modified to account for the morphology of the solid–liquid interface. Melting and solidification occurring during the welding process are modeled using a modified enthalpy– porosity technique. Key issues regarding turbulent transport in a GTAW process are highlighted by comparing the results from the turbulence modeling with the corresponding ones from a laminar model, keeping all process parameters unaltered. A scaling analysis is also performed to obtain order-of-magnitude estimates of certain key features of a turbulent weld pool. The scale analysis predictions show good agreement with the numerical results.