Leidenfrost Self-Rewetting Drops

As
discovered by Leidenfrost, liquids placed on very hot solids
levitate on a cushion of their own vapor. This is also called the
calefaction phenomenon, a dynamical and transient effect, as vapor
is injected below the liquid and pressed by the drop weight. To account
for the film vapor, we consider the surface tension magnitude as well
as the Marangoni effect (in particular the thermal one) which arise
with imbalance of surface tension forces. For standard liquids, these
forces contribute to amplify the thickness of the film layer and the
levitation of the droplet. Our findings imply the ability of recent
binary mixture liquids, called self-rewetting fluids, to reduce the
vapor film thickness and demonstrate the powerful influence exerted
by different binary mixtures to enhance the heat transfer at high
temperature. Such self-rewetting fluids are presenting a high value
of surface tension at high temperature, and in which the Marangoni
forces are inversed as from critical temperature. We consider our
assay to be a way for improvement in the high temperature mass cooling
applications.