Predictions of flow velocity and velocity boundary layer thickness at the surface during laser melting of ceramic materials

A scaling analysis for momentum and heat transport in the laser-induced melt pool of ceramic materials has been carried out to predict the flow velocity and velocity boundary layer thickness at the melt surface. Compared with analyses available in the literature for momentum and heat transport in the melt pool formed by other high energy density beams, the present scaling analysis has more appropriately incorporated the volumetric heating source in the energy equation and quantified the relative amounts of laser energy consumed by thermal diffusion and by the traverse of the workpiece. The scaling predictions have been assessed by comparison with numerical results of a case study obtained by the present authors, and good qualitative agreement was observed