Micropatterned Aluminium Surfaces for Anti-icing and Anti-frosting Applications

Abstract

Developing anti-icing and anti-frosting technology is vital for many different energy generation and consumption systems such as wind turbines, aircraft and heat exchangers, where ice and frost formation is a barrier for efficiency and can severely damage infrastructure and injure people.

This work investigates anti-icing and anti-frosting properties of aluminium hierarchical structures with varying geometric parameters. These structures consisted of micro-milled microstructures with nanoscale roughness due to the milling. Fixed-pitch and gradient-pitch structures were tested, the latter of which have not been tested for ice adhesion previously. The structures are characterised for their geometric and surface wetting properties using a scanning electron microscope and a goniometer respectively, then tested for anti-icing properties using a force probe and anti-frosting properties using a wind tunnel with Peltier cooling. Both systems were custom built for this purpose.

These aluminium surfaces rely only on topographic modifications - no lubricants, coatings or polymers, which tend to be prone to damage and impractical to reapply in many applications. It was found that these gradient-pitch microstructures had equivalent or better anti-icing/anti-frosting performance than the fixed-pitch structures for both ice adhesion and frosting delay.