Energy Stable Simulation of Two-Phase Equilibria with Capillarity

Abstract

We consider the affect of capillary pressure on the Van der Waals fuid and on the Peng-Robinson fluid by minimizing total Helmholtz energy in given total volume, temperature, and total moles. We propose simple but conditionally energy stable numerical schemes, and we provide interesting numerical examples. We compare our numerical results with the prediction of Kelvin’s equation, indicating that Kelvin’s equation works well only when the temperature is not too low.