Mobility and interactions of weakly nonwetting droplets

Lubrication equations based on diffuse interface theory are applied to description of slow motion and interaction of droplets on solid support. For the case of quasistationary motion of a weakly nonwetting fluid, we derive integral relations reducing the problem to computation of ratios of applicable thermodynamic forces to a dissipative integral characterizing an individual droplet. This allows us to describe the droplet motion without computing explicitly the distortion of their shape. Explicit computations are carried out for a droplet sliding on an inclined plane, and for an ensemble of droplets interacting through the precursor layer. (C) 2004 American Institute of Physics.