In this paper, a superhydrophobic surface is used to increase the flashover voltage when water droplets are present on a silicone rubber surface. The dynamic behavior of a water droplet and the associated flashover characteristics are studied on common and superhydrophobic silicone rubber surfaces under a high DC voltage. On common silicone rubber, the droplet elongates and the flashover voltage decreases with increasing droplet volume and conductivity. In contrast, the droplet slides off the superhydrophobic surface, leading to an increased flashover voltage. This droplet sliding is due to the low adhesion of the superhydrophobic surface and a sufficiently high electrostatic force provided by the DC voltage. Experimental results show that a superhydrophobic surface is effective at inhibiting flashover.

Superhydrophobic surface has aroused much interest among researchers due to the low adhesion between water and a substrate surface. This study focuses on the influence of the low adhesion of superhydrophobic surface on flashover characteristics under wet conditions. The flashover experiments were conducted under two different wet conditions. One was placing a constant volume droplet on the silicone rubber. The other one was that silicone rubber was wetted by salt fog. It was found that the adhesion between water droplets and a superhydrophobic surface was very low because of the presence of air cushion. Accordingly, water droplets were easy to slide on a superhydrophobic surface under the effect of electric filed. The sliding of droplets could provide a longer insulation path before flashover occurred. Results showed that flashover voltage could be improved greatly on a superhydrophobic silicone rubber surface.

The superhydrophobic surface (SHPS) with a contact angle (CA) of 151°and a sliding angle (SA) of 0.5°was successfully fabricated on aluminium stranded wires (ASW) via a simple chemical etching process, and subsequently covered with a fluoroalkylsilane film. The wettability and microstructure of consequent SHPS was characterised by CA/SA, scanning electron microscopy and 3D colour laser scanning microscope, respectively. A simple dynamic icing experimental system was performed. The corrosion resistance and dynamic anti-icing property were also investigated by acid/alkaline solution corrosion and dynamic icing test. The results showed that, due to the combined effect of micro-nano structure, air cushion and capillary. The SHPS possessed great corrosion-resistant and anti-icing properties; moreover, the anti-icing property increased by 68.2% and the starting icing time was delayed by six times, which should be critical to the potential application in industry.

The study on superhydrophobicity is based on the wetting behavior of droplets on the rough surface. The wetting behavior on the red rose petal was observed by optical microscope at micrometer scale. Results showed that the wetting behavior was dynamic and air moved slowly between the droplet and the red rose petal. Many isolated air cushions were also found at the interface. In order to explain the relationship between the wetting behavior and the high adhesive force on the rose petal, a geometric model about solid-liquid-air three phase interface was proposed. The adhesion on the rose petal mainly depended on the sealed air inside the interface which could not connect to the atmosphere and the strong association of the solid/liquid at Wenzel wetting domains in this model.

Aluminum is widely used in transmission lines, and the accumulation of ice on aluminum conductor may inflict serious damage such as tower collapse and power failure. In this study, super-hydrophobic surface (SHS) on aluminum conductor with micro-nanostructure was fabricated using the preferential etching principle of crystal defects. The surface microstructure and wettability were investigated by scanning electron microscope and contact angle measurement, respectively. The icing progress was observed with a self-made icing experiment platform at different environment temperature. The results showed that, due to jumping and rolling down of coalesced droplets from SHS of aluminum conductor at low temperature, the formation of icing on SHS could be delayed. Dynamic icing experiment indicated that SHS on aluminum conductor could restrain the formation of icing in certain temperature range, but could not exert influence on the accumulation of icing. This study offers new insight into understanding the anti-icing performance of actual aluminum conductor.