Jet engine applications are rich areas for applying actuators to both improve engine efficiency on take-off and landing, and also to suppress jet noise. In both drones and small aircraft, wing twist and active flight surface reconfigurations have been well-established as providing the significant aerodynamic benefits. Why these actuators have not become more established in airframes is due to the low transformation temperatures of the SME alloys as compared to the service environment, fatigue and stability issues and slow transformation times. These issues are solved by using this technique. Nacelle actuators are now flat SME plates, and can be modified by this technique to generate the required stroke with a responsive bandwidth by taking advantage of bleed gas from the jet exhaust. Similarly wIng twist actuators can be made as a high fatigue life porous actuator, allowing for rapid actuation. The high transformation temperatures that TiNi-Hf demonstrates allows for application in the hot engine environment. Finally, there is a need for vibration isolation materials that are responsive at low temperatures. Fine porous TiNi weaves can be made o allow for damping applications down on -80C.
Waste heat to power is a challenging area to exploit commercially, especially at temperatures below 170C, due to both thermodynamics and the lack of materials that can exploit these temperatures effectively. Shape memory alloy foams have been shown by Shape Change Technologies to effectively capture most of the waste heat from hot water/steam sources. What is needed is for a more tailored transformation temperature to capture and convert higher temperature steam and a long and reliable fatigue life. This technique, if successful, will provide the enabling fabrication technique to provide long fatigue lifes, with tailorable porosity. The market for converting waste heat from Combined Heat and Power units and geothermal plants is large given the capacity of the plants and the opportunity to sell reclaimed power back to the grid.
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