Time delay of water contact with acrylic polyurethane super-hydrophobic surfaces

Super-hydrophobic surfaces have recently drawn significant attention in application towards enhancement of pollution flashover and reduction of ice accumulation on insulators. This paper presents a new way to delay water contact with the surface via its elastic collision with the rebounding droplets from the super-hydrophobic surface. The water mass contacted with the surface will be reduced by the rebounding droplets. Hydrophobic characteristics, contact times, spreading times and spreading coefficients of water droplets on super-hydrophobic surfaces are presented. Experimental results show that the super-hydrophobic surface has smaller contact time, spreading time and spreading coefficient than that of the bare glass. Specific Web and Reynolds numbers can lead to the elastic rebounding between water droplets, delaying the water contact with the super-hydrophobic surface.