Variation in Anti-icing Power of Superhydrophobic Electrothermal Film under Different Temperatures and Wind Speeds

Abstract

Anti-icing with low-energy consumption has important research value for unmanned aerial vehicles. In this study, a superhydrophobic electrothermal film for anti-icing applications was designed and prepared, and power consumption experiments were conducted at different temperatures and wind speeds in an icing wind tunnel. The anti-icing power consumption of the superhydrophobic electrothermal film was lower than that of a traditional electrothermal film. As the temperature decreased or the wind speed increased, the anti-icing power consumption of the two types of electrothermal films increased. A heat flux model was used to analyse the experimental results. It can be concluded that the water collection rate per unit area W and wetting coefficient ξ w are the main factors affecting the power consumption of the superhydrophobic electrothermal film. When the temperature decreased and the wind speed increased, the contact time and contact area between the droplet and the surface affected W and ξ w . Thus, this study is of considerable significance for the design of superhydrophobic electrothermal films for novel anti-icing applications in the future.

Effects of asymmetric cooling and surface wettability on the orientation of the freezing tip

“…This vortex convective motion observed in the experiment intensifies heat transfer in the water layer. The Grashof number which quantifies the ratio of the buoyancy force to the viscous force is directly proportional to Δ𝜌 × 𝐻 3 ~𝜑(Δ𝑇) 2 𝑅 3 , where 𝐻 is the current thickness of the water layer above the ice-water interface, Δ𝑇 is the temperature difference in this layer, and 𝑅 is the droplet radius. Obviously, the small values of 𝜑 and 𝑅 indicate that the average velocity of the vortex motion of water in the droplet is very small (this was also observed in the experiment).…”

“…Icing is a widespread process, which is crucially important for multiple applications, including civil enginnering 1 , aircraft 2,3 and energy production industries. 4 Insights into the physics of the icing are also important for understanding ice friction.…”

A Review on Superhydrophobic Surface with Anti-Icing Properties in Overhead Transmission Lines

“…In addition, Kermani et al [106] simulated the fracture behavior of atmospheric ice on bare conductors under different wind speeds and found it sometimes occurred during line galloping when stresses arose at a wind speed of 5 m/s. However, high wind speed could be conducive to the anti-icing behavior of superhydrophobic surfaces compared with Al substrates due to the bouncing behavior of water droplets and low ice adhesion [94,105]. Xue et al [105] studied the anti-icing properties of superhydrophobic electrothermal film under different temperatures and wind speeds and concluded the main factors to be water collection rate per unit area and wetting coefficient.…”

“…However, high wind speed could be conducive to the anti-icing behavior of superhydrophobic surfaces compared with Al substrates due to the bouncing behavior of water droplets and low ice adhesion [94,105]. Xue et al [105] studied the anti-icing properties of superhydrophobic electrothermal film under different temperatures and wind speeds and concluded the main factors to be water collection rate per unit area and wetting coefficient. Belaud et al [94] studied superhydrophobic aluminum oxide surfaces for aeronautic applications and found low atmospheric ice adhesion under wind tunnel tests.…”

“…In addition, ultraviolet exposure is also a slow aging factor resulting in the deteriorated superhydrophobic properties of coatings [110]. Moreover, contamination deposits are involved in pollutants and sand dust, as reflected in the pol- Nevertheless, the unique operating environments of conductors [104] also include wind velocities [94,[105][106][107], wind direction [106,107], high temperatures, ultraviolet exposure, contamination deposits, corrosion, mechanical wear and corona loss. Generally, wind speed is inversely proportional to temperature, as reflected in the icing thickness of a bare conductor [105], even resulting in the line galloping [106,107].…”