Research on fluid dynamics during laser deep penetration welding

A mathematical model that is capable of simulating the fluid flow and heat transfer during fully penetration laser welding is developed to study: the shape of the keyhole and its stability; velocity vectors and distribution in the weld pool. Firstly, a new combination heat source model consisting of a rotary Gaussian volumetric heat source and a double ellipsoidal volumetric heat source during laser keyhole welding is developed. It represents substantial characteristic of heat transfer of the keyhole. Secondly, A mathematical model for the simulation of heat transfer and fluid flow in weld pool phenomena during deep penetration laser beam welding based on a numerical solution of the conservation equations of energy, momentum and mass is presented. and verification and validation tests were carried out.