title: Atmospheric Ice Adhesion on Water-Repellent Coatings: Wetting and Surface Topology Effects.
abstract: Recent studies have shown the potential of water-repellent surfaces such as superhydrophobic surfaces in delaying ice accretion and reducing ice adhesion. However, conflicting trends in superhydrophobic ice adhesion strength were reported by previous studies. Hence, this investigation was performed to study the ice adhesion strength of hydrophobic and superhydrophobic coatings under realistic atmospheric icing conditions, i.e., supercooled spray of 20 μm mean volume diameter (MVD) droplets in a freezing (-20 °C), thermally homogeneous environment. The ice was released in a tensile direction by underside air pressure in a Mode-1 ice fracture condition. Results showed a strong effect of water repellency (increased contact and receding angles) on ice adhesion strength for hydrophobic surfaces. However, the extreme water repellency of nanocomposite superhydrophobic surfaces did not provide further adhesion strength reductions. Rather, ice adhesion strength for superhydrophobic surfaces depended primarily on the surface topology spatial parameter of autocorrelation length (Sal), whereby surface features in close proximities associated with a higher capillary pressure were better able to resist droplet penetration. Effects from other surface height parameters (e.g., arithmetic mean roughness, kurtosis, and skewness) were secondary.
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Virginia , Charlottesville, Virginia 22904, United States.|Rolls-Royce North America, Indianapolis, Indiana 46241, United States.|Rolls-Royce, Plc. Derby DE24 8EJ, U.K.
authors.forename: Yong Han
authors.initials: YH
authors.lastname: Yeong
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Virginia , Charlottesville, Virginia 22904, United States.|Rolls-Royce North America, Indianapolis, Indiana 46241, United States.|Rolls-Royce, Plc. Derby DE24 8EJ, U.K.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Milionis
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Virginia , Charlottesville, Virginia 22904, United States.|Rolls-Royce North America, Indianapolis, Indiana 46241, United States.|Rolls-Royce, Plc. Derby DE24 8EJ, U.K.
authors.forename: Eric
authors.initials: E
authors.lastname: Loth
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Virginia , Charlottesville, Virginia 22904, United States.|Rolls-Royce North America, Indianapolis, Indiana 46241, United States.|Rolls-Royce, Plc. Derby DE24 8EJ, U.K.
authors.forename: Jack
authors.initials: J
authors.lastname: Sokhey
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Virginia , Charlottesville, Virginia 22904, United States.|Rolls-Royce North America, Indianapolis, Indiana 46241, United States.|Rolls-Royce, Plc. Derby DE24 8EJ, U.K.
authors.forename: Alexis
authors.initials: A
authors.lastname: Lambourne