Evaporation of a sessile oil drop in the Wenzel-like regime

In this work, we present an experimental study of the evaporation of oil drops deposited on both textured and smooth silicon substrates at two different temperatures (20 degrees C and 270 degrees C). We show that the sessile drops take a hexagonal form and are linked by an oil film (a droplet sitting on a mixture of solid and liquid). This wetting regime represents the Wenzel-like regime. We are particularly interested in the propagation of the oil film on the textured surface over time. The effect of the surface fraction of the micro-textures empty set and the temperature of the substrate T-h on the film propagation were also studied. We reveal that the spreading length of the oil drops increases as empty set decreases and T-h increases. We also demonstrate that the textured surface favors oil drop evaporation.