Surface contamination by ice poses a hazard to industries ranging from power transmission to transportation by ground, sea and air. The aviation industry is particularly affected by icing phenomena that manifest as a reduction in fuel efficiency and compromised aerodynamic lift, which can impair flight safety. [1] Consequently, there is a worldwide scientific effort to understand the physics of icing, aiming to develop effective and efficient anti-icing and de-icing strategies. [2] Icing can occur while aircraft are on the ground or in the air. On the ground, when freezing precipitation contaminates the surfaces of an aircraft, safety protocols delay that aircraft's scheduled flight. In fact, contamination necessarily needs to be removed since it alters aerodynamic properties and, like on a snow-covered car, ice fragments can be sheared off by aerodynamic drag and fly into the engines. A typical ground de-icing operation consists in directly spraying an aircraft with a mixture of warm water and glycol. [3] Generally, ice contamination in the air is caused by the impact of supercooled water droplets found in clouds. Depending on several conditions, droplets may either stick to a surface at the point of impact or flow along the surface in the direction of airflow. In the latter case they form a thin film of water, where surface tension forces them into rivulets. [1,4] While fixed-wing aircraft cruise at altitudes above where icing can occur, helicopters operate at altitudes where supercooled water droplets are known to occur (temperature range between −40 and 0 °C). [5] Aviation safety authorities demand to avoid flying into known icing conditions and, as an additional precaution, they enforce through certification, the equipment of ice protection systems (IPS) to all commercial aircraft. [6] IPS can provide either anti-icing, de-icing, or both countermeasures. [1,7] Thermal anti-icing describes a condition where all impinging water droplets are evaporated by a high-temperature surface. A de-icing countermeasure is one where ice is removed from a surface once it has reached a subjectively critical size. [7] Commercial airliners, for the most part, are equipped with thermal IPS that use hot air drawn from the compressor of their turbofan engines, which is diverted to critical surfaces Forward facing aerodynamic surfaces such as rotors and wings are susceptible to ice build-up when exposed to atmospheric icing conditions. If not removed, accumulated ice on aircraft surfaces affects aerodynamics or rotation balance, which can ultimately lead to increased fuel consumption, reduced operational performance and to potentially hazardous situations. Laser surface structuring is proposed as an alternative technology to coatings for achieving icephobic properties and support anti-icing and de-icing processes on aerodynamic surfaces. However, to authors' knowledge, no study available in the literature reports on the icing behavior of microtextured curved aerodynamic profiles and the effect of the laser surface treatment on the...
