Heat transfer and dynamics of the droplet on a superheated surface

The conditions governing the collapse of a "Leidenfrost drop", e.g. a liquid drop supported by a vapour film on a heated surface was studied analytically. Robust analytical model for the phenomenon has been developed and numerical simulation has been done. The model was represented by two second-order non-linear differential equations for the radius of evaporating drop and its distance over the heated surface. The results obtained have shown the high-frequent oscillations of the drop over the hot plate until complete evaporation of the drop occurs. In contrast with existing precise complex models, the mathematical model developed was simple and could be used for the qualitative estimation of different parameters and quantitative estimation of the integral behaviours of the drop such as time for complete drop evaporation. The effects of surfactants on the Leidenfrost phenomenon and its industrial applications were discussed.