Characterization the Anti-Icing and Performance and Rain-Erosion Resistance of a Super hydrophobic Coating for UAV Icing Mitigation

An experimental study is conducted on a super hydrophobic coating (WX 2100) to characterize the glaze ice accretion characteristics and understand the rain erosion effects. This study is performed using the unique Icing Research Tunnel (IRT), and the rain erosion testing rig available at Iowa State University. Hybrid anti-icing tests were performed by using a heating element to cover 10% of the chord length, and the entire model was coated with the WX 2100 coating to facilitate water runback. Measurement results indicate that an applied power density of 4.5 kW/m² to the thermal film was enough to make the entire surface of a UAV airfoil/wing model ice-free for the super hydrophobic coating, in contrast to at least 25kW/m² required for the enamel hydrophilic surface. To characterize the coating durability, the static, advancing, and receding contact angles, as well as the ice adhesion strength, are measured before and after rain erosion tests, given that both variables are a function of the duration of the rain erosion testing. A decrease in the contact angle and surface roughness, along with an increase in ice adhesion, was observed throughout 60 minutes of accelerated rain erosion at 80 m/s with LWC = 16.0 g/m³.