Utilization of the second gradient theory in continuum mechanics to   study motions and thermodynamics of liquid-vapor interfaces
  A thermomechanical model of continuous fluid media based on second gradient theory is used to study motions in liquid-vapor interfaces. At equilibrium, the model is shown to be equivalent to mean-field molecular theories of capillarity. In such fluids, conservative motions verify first integrals that lead to Kelvin circulation theorems and potential equations. The dynamical surface tension of liquid-vapor interfaces is deduced from viscous fluid equations. The result provides and explains the Marangoni effect. 
Henri Gouin (M2P2)
physics.flu-dyn cond-mat.soft physics.chem-ph