An experimental study of evaporative cooling from liquid droplets impinging on a hot surface

Abstract

We have performed a series of experiments to characterize the different regimes observed in drop impacts during evaporative cooling of heated surfaces. We found four regimes which were named splashing, fizzing, flat film, and marbling based on the dynamic properties of the drop impact. We found that the emergence of these regimes is primarily controlled by the Jacob number, a dimensionless group describing the ratio of sensible to latent energy absorbed during liquid-vapor phase change. Using our classification scheme, we can predict a range of useful Jacob numbers to use in the cooling of electronic components. From these Jacob numbers, we can extract the material properties of a fluid required to cool a given system.