Icing conditions create significant safety concerns within the aircraft turbomachinery, and in surrounding nacelles, stators, and thrust vectoring surfaces. Icephobic surfaces could significantly reduce the accretion of ice within these components, allowing for safer operation. However, even after decades of research, there are no known icephobic coatings that can function in aircraft engine realistic air speeds and operational environments. HygraTek has recently developed extremely durable elastomeric coatings, that display some of the lowest ice-adhesion strength values ever reported, and can be spray or dip-coated onto any substrate. We have also recently developed the first-ever metal-based icephobic coatings. These are the most durable icephobic coatings ever produced, and to our knowledge, the only coatings that have passed rain-erosion testing. As part of this proposal, we will evaluate the suitability of the developed elastomeric and metal-based icephobic coatings for passively shedding ice under engine realistic operational environments. Apart from extensive durability and ice-adhesion testing, we will evaluate ice-accumulation under different icing conditions in a wind tunnel. We will also evaluate compatibility with legacy de-icing systems, as well as the heat required to de-ice coated airfoils. Finally, we will conduct rain erosion and high cycle fatigue testing on the best icephobic system developed.
Benefit: Icephobic coatings for turbomachinery has applicability in commercial aviation, as well as aerospace launch applications. Icing conditions create safety concerns within the turbomachinery and in surrounding nacelles, stators, and thrust vectoring surfaces. Icephobic coatings reduce turbomachinery damage resulting from ice buildup and subsequent release into the high-speed rotating parts of the turbomachinery. Of particular concern is ice formation on stators (i.e., static non-rotating components). Stators are integral components of turbomachinery whether the specific function is guide-vanes, vortex-shedders, compressor stators, or lift-fans in VSTOL aircraft. Ice-buildup in fuel lines, due to in part to the presence of water in fuels, creates engine safety concerns. Icephobic coatings have a wide range of commercial applications in non-turbomachinery applications as well. Durable icephobic surfaces impact directly the safety across virtually all transportation vehicles (e.g., airplanes, trains, automobiles), in addition to reducing the operating energy costs for the same transportation vehicles by enabling traditional air conditioning to be replaced by high-efficiency heat pump systems (that are now currently limited due to icing at lower environmental temperatures). Icephobic coatings enable significant energy savings in refrigeration equipment and ice makers, as well as enabling lower capital and operating costs of thermal (i.e., ice) energy storage systems.
Keywords: Elastomeric, Elastomeric, icephobic coatings, functional coatings surviving aerospace rain erosion conditions, low ice adhesion strength, metal
