Contact line behavior for a highly wetting fluid under superheated conditions

The contact line behavior of a highly wetting, dielectric liquid (FC-72) droplet under superheated conditions is investigated. Relatively large macroscopic contact angles atypical of FC-72 droplets were observed under superheated conditions. The addition of a non-condensable dissolved gases in the system increased the contact angle at a given superheat. Numerical simulations of the transport phenomena near the microscopic three phase contact line were performed that show how the macroscopic contact angle is related to the superheat and thickness of the adsorbed film ahead of the contact line. The use of a macroscopic contact angle that is a function of superheat in established models for bubble departure diameter and the onset of nucleate boiling enhanced the ability of those models to describe the behavior of highly wetting fluids.