Influence of Temperature-Dependent Physical Properties on Liquid Metal Droplet Impact Dynamics

Abstract The dynamics of a metal droplet impacting on a substrate surface has been studied numerically in this report. Numerical solutions of the Navier–Stokes and energy equations show the evolution of the droplet as it spreads upon impact with the substrate while simultaneously undergoing solidification. The interplay of different forces including inertia, viscous, and surface tension, coupled with solidification of the molten material in layers lead to complex flow dynamics. The change in density and viscosity owing to a change in temperature resulting from the cooling process is found to influence the spreading of the droplet significantly. The model was exercised for three different materials, namely, aluminum, copper, and nickel to determine the final splat radius as well as the spreading time. The surface tension forces as well as solidification rates were found to be the dominant factors in determining the above parameters as well as the shape of the splat during spreading. The results were found to be in good agreement with an existing analytical model.