Low-Adhesion Surface Evaluation on an Airfoil in the NRC AIWT

The performance of low-adhesion surfaces in a realistic, in-flight icing environment with supercooled liquid droplets is evaluated using a NACA 0018 airfoil in the National Research Council of Canada Altitude Icing Wind Tunnel. This project was completed in collaboration with McGill University, the University of Toronto and the NRC Aerospace Manufacturing Technologies Centre in March 2022. Each collaborator used significantly different methods to produce low-adhesion surface treatments. The goal of the research program was to demonstrate if the low-adhesion surfaces reduced the energy required to de-ice or anti-ice an airfoil in an in-flight icing environment. Each collaborator had been developing their own low-adhesion surfaces, using bench tests in cold rooms and a spin rig in the wind tunnel to evaluate their performance. The most promising surface treatments were selected for testing on the airfoil. The de-icing and anti-icing performance of the low-adhesion surfaces was compared to that of a bare aluminum leading edge using a heated-air piccolo tube ice protection system. Overall, the surface treatments were not found to provide any significant improvement in de-icing or anti-icing performance over a bare aluminum surface. However, the results were very useful in identifying ways to improve the surface treatments for better performance in icing conditions and these lessons may be integrated into future test campaigns.