Effect of beam oscillation on the fluid flow during laser welding

In the present study, a finite element based numerical model is developed to evaluate heat transfer and fluid flow during the laser welding process with a moving heat source. The developed model solves the fully coupled equations of incompressible fluid flow and heat transfer. In this study, laser beam welding involving non-oscillating to oscillating beam is compared with both conditions under similar heat input per unit length i.e., same power and welding speed. Dimensionless coefficients for mass and heat transport were used to analyse the effects of Marangoni flow and thermal buoyancy. Varying combinations of radius and frequency of oscillations are studied at a constant circumferential velocity.