Modelling Wetting Behaviour

Abstract

Our aim is to improve the macroscopic description of the wetting property. Wettability characterises a capillary behaviour implying three partners : a liquid F⁽¹⁾ a solid S and a complementary one which is the surrounding fluid F⁽²⁾ “What are the parameters adequate to describe such behaviour ?” A first simple approach, lying on the statics of fluids and Laplace’s law, produces a mathematical model for the equilibrium of a F⁽¹⁾/F⁽²⁾ interface, in the presence of a solid wall. That model induces a complementary experimental approach for obtaining a phenomenological relation between three unavoidable parameters intervening in the mathematical model: the spreading parameter η the contact angle θ and the contact mean curvature μ At the same time, a thermomechanical research is implemented to obtain a general framework of capillary behaviour; it lies on the Cahn-Hilliard Fluid Theory, and leads to the notion of Fluid with internal wettability.