Multi-layer de-icing skin for aircraft platforms
An ice resistant structure is provided which includes a self-supporting, structural platform, a retaining, protective layer and a subsurface anti-icing (AI) and/or de-icing (DI) layer. The retaining, protective layer is disposed over the self-supporting, structural platform. The subsurface anti-icing (AI) and/or de-icing (DI) layer is located between the self-supporting, structural platform and the retaining, protective layer. The subsurface Al and/or DI layer is a functional layer such that an Al and/or DI agent is released to a surface of the retaining protective layer by an activation mechanism responsive to a change in an environmental condition.
1. An aircraft ice resistant structure, comprising:
a self-supporting, structural platform;
a retaining, protective layer disposed over the self-supporting, structural platform; and
a subsurface anti-icing (AI) and/or de-icing (DI) layer located between the self-supporting structural platform and the retaining, protective layer, the subsurface AI and/or DI layer being a functional layer such that an AI and/or DI agent is released to a surface of the retaining protective layer by an activation mechanism responsive to a change in an environmental condition, the AI and/or DI agent being hydrophobic agents, wherein the activation mechanism is an active activation mechanism, wherein the active activation mechanism operates using physical constriction to release the AI and/or the DI agent.
2. The aircraft ice resistant structure of claim 1 wherein the structural platform defines an aircraft wing and the retaining protective layer and the subsurface AI and/or DI layer define a skin on at least a portion of the aircraft wing.
3. The aircraft ice resistant structure of claim 2 wherein the aircraft wing is a Unmanned Aerial Vehicles (UAV) wing.
4. The aircraft ice resistant structure of claim 1 wherein the activation mechanism further includes a passive activation mechanism.
5. The aircraft ice resistant structure of claim 4 wherein the environmental condition is temperature.
6. The aircraft ice resistant structure of claim 4 wherein the passive activation method drives the AI and/or DI agent onto the surface using phase separation.
7. The aircraft ice resistant structure of claim 4 wherein the passive activation method drives the AI and/or DI agent onto the surface using phase separation and differences in rates of thermal expansion such that the differences in the rates of thermal expansion physically drive the AI and/or DI agent to the surface.
8. The aircraft ice resistant structure of claim 4 wherein the passive activation method drives the AI and/or DI agent onto the surface using chemical affinity changes of the retaining, protective layer and the subsurface AI and/or DI layer to the AI and/or DI agent.
9. The aircraft ice resistant structure of claim 4 wherein the passive activation method reversibly drives the AI and/or DI agent onto the surface such that the AI and/or DI agent is delivered onto the surface of the retaining protective layer in response to a first environmental condition and at least some of the AI and/or DI agent returns to the subsurface AI and/or DI layer in response to a second environmental condition.
10. The aircraft ice resistant structure of claim 9 wherein the first environmental condition is a temperature at or below about 0° C. and the second environmental condition is a temperature above about 0° C.
11. The aircraft ice resistant structure of claim 9 wherein the AI and/or DI agent is substantially preserved after being delivered onto the surface and returned to the subsurface AI and/or DI layer.
12. The aircraft ice resistant structure of claim 1 wherein the retaining, protective layer has AI and/or DI characteristics.
13. The aircraft ice resistant structure of claim 12 wherein the AI and/or DI characteristics are imparted by a chemical nature of agents contained in the retaining, protective layer.
14. The aircraft ice resistant structure of claim 12 wherein the AI and/or DI characteristics are imparted by a structural nature of the retaining, protective layer.
15. The aircraft ice resistant structure of claim 14 wherein the retaining, protective layer has a microstructure or nanostructure.
16. The aircraft ice resistant structure of claim 1 wherein the DI agent is selected from the group consisting of a hydrophobic oil, gel, and a fluorinated material.
17. The aircraft ice resistant structure of claim 1 wherein the subsurface AI and/or DI layer includes a slippery liquid-infused porous surface (SLIPS) material.
18. The aircraft ice resistant structure of claim 1 wherein the retaining, protective layer includes a fluorine-based polymer.
19. The aircraft ice resistant structure of claim 18 wherein the fluorine-based polymer includes Ethylene Tetrafluoroethylene (ETFE).
20. The aircraft ice resistant structure of claim 1 wherein the subsurface AI and/or DI layer includes polydimethylsiloxane (PDMS) and the AI and/or DI agent includes an alkyl molecule.
21. The aircraft ice resistant structure of claim 1 wherein the AI and/or DI agent in the subsurface anti-icing (AI) and/or de-icing (DI) layer is replenishable.
22. The aircraft ice resistant structure of claim 21 , wherein the anti-icing (AI) and/or de-icing (DI) layer is replenishable by migration of AI or DI chemical agents from outside of outer layers of the ice resistant structure through intermediate layers to chemical agent retaining sub-surface layers.
23. The aircraft ice resistant structure of claim 1 , wherein at least some of the layers are substantially transparent to selected wavelengths of electromagnetic radiation.
24. The aircraft ice resistant structure of claim 23 , wherein, the at least some of the layers are substantially transparent to sunlight.
25. The aircraft ice resistant structure of claim 24 further comprising semiconductor photovoltaic cells located within, between and/or below one or more of the layers such that the photovoltaic cells receive sufficient sunlight to produce electrical carriers therein.
26. The aircraft ice resistant structure of claim 23 , wherein at least some of the layers are substantially transparent to radio frequency (RF) radiation.
27. The aircraft ice resistant structure of claim 26 further comprising one or more antenna structures secured to the structural platform to function as part of RF receiving and/or transmitting devices.
28. The aircraft ice resistant structure of claim 23 , wherein at least some of the layers are substantially permeable to chemical, radiative, or analogous agents, indicators or signals which are to be detectable for sensors.
29. The aircraft ice resistant structure of claim 28 further comprising one or more sensory devices or structures for chemical, radiative or analogous agents for performing sensory or informational detection and/or analysis.