Scaling of anisotropic wetting behavior of water drop configuration arising from parallel groove-textured stainless steel surfaces

Abstract

Abstract Understanding the wetting behavior of stainless steel surfaces can help in resolving many socio-economic challenges faced modern day engineering developments. In this research paper, investigations have been carried for understanding the role of surface one-dimensional microgrooves on the wetting behavior by the water drop liquid using the liquid drop shape configuration captured in the view direction parallel and orthogonal to surface microgrooves. Because of the variation in wetting characteristics between these two directions i.e., anisotropic wetting behavior, the liquid drop has attained ellipsoidal shape configuration in the microgroove textured stainless steel surfaces. Detailed investigation has been carried out in understanding the role of microgroove geometrical sizes i.e., width and depth and the spacing between the grooves on the wetting behavior in terms of contact diameter (D) and contact angle (θ). Overall, the wetting dynamics has been characterized by looking at the variation of eccentricity (ε, as a ratio between D in the direction parallel to microgroove and the spreading diameter in the direction orthogonal to microgroove) and wetting anisotropy (Δθ, as a difference in θ between the direction orthogonal and parallel to microgroove) with the microgroove depth parameter,φ ( as a ratio between the microgroove depth and width) and the groove spacing parameter, ξ (as a ratio of the spacing between the grooves and the groove width). By and large, with increase in surface non-dimensional geometrical parameters, φ and ξ, the parameters quantifying eccentricity, ε and Δθ decreases. So, the liquid drop shape configuration shifts towards spherical cap from ellipsoidal cap