Special Session 10: Analysis of diffuse and sharp interface models

Droplet models with singular potentials: equilibria and travelling waves

Lorenzo Giacomelli
Sapienza University of Rome
Italy
Co-Author(s):    
Abstract:
We look at spreading phenomena under the action of singular potentials modeling repulsion between the liquid/gas interface and the substrate. First we briefly review the statics: depending on the form of the potential, the macroscopic profile of minimizers (when they exist) can be either droplet-like or pancake-like, with a transition profile between the two at zero spreading coefficient. Then we focus on the dynamics, assuming null slippage at the contact line. Based on formal arguments and numerical evidences, we report that travelling-wave solutions generically exist and have finite rate of bulk dissipation, indicating that singular potentials stand as an alternative solution to the contact-line paradox. In agreement with steady states, travelling-wave solutions have finite energy for mild singularities. Time permitting, we also discuss a selection criterion for travelling waves, based on thermodynamically consistent contact-line conditions modeling friction at the contact line. Based on joint works with Riccardo Durastanti (Universiy of Naples Federico II).