experimental study of capillary effects on the dynamics of surface evaporation of water droplets

the evaporation of liquid droplets is of fundamental importance in a large number of practical situations ranging from technological applications such as ink-jet printing, spray cooling and various coating processes, to a variety of biological and geophysical contexts. in this study, the behavior of the surfaces of glass, plexiglas, aluminum and copper in the evaporation of water droplets is studied experimentally. it is assumed that the transport of vapour in the atmosphere is dominated by diffusion and other effects are ignored. experimental observations show that the surface evaporation on the surfaces of aluminum and copper are generally carried out in a constant contact area while the water droplets on the surfaces of glass and plexiglas usually experience the sliding behavior in certain timescales. furthermore the changes of surface energy during the process of evaporation of water droplets on the surface are also discussed.