Application of the Lattice-Boltzmann method to wetting on anisotropic textured surfaces: Characterization of the liquid-solid interface.

HYPOTHESIS

To understand the relationship between topography and wetting, it is not enough to study the contact angle. Indeed, the liquid-solid interface plays an important role in wetting. However, data such as the total triple line length, the wetting area and the anchoring depth are inaccessible or difficult to obtain experimentally. This work proposes to overcome the experimental limitations by using a numerical approach to characterize the wetting behavior on textured surfaces.

METHODS

The wetting behavior of an anisotropic textured surface was compared for both experimental and numerical approaches. The experimental wetting is characterized by sessile drop experiments. The simulations were performed by applying the pseudo-potential Lattice-Boltzmann method. The numerical approach was then used to predict the wetting behavior of different materials.

FINDINGS

The simulations capture both the wetting state and the contact angle, in accordance with the experimental observation. Without making any assumptions about the interfacial shape and anchoring, the simulation allows to characterize the liquid-solid interface by quantifying the total length of the triple line and the wetting area. Simultaneously, the simulations enable the characterization of impregnation within textures for complex mixed regimes.