ADVANCED COOLING TECHNOLOGIES INC — National Aeronautics and Space Administration SBIR Phase I: Z2

Description

<p style="margin-left:0in; margin-right:0in">NASA&rsquo;s Space Technology Mission Directorate (STMD) is investigating technologies for thermal control systems (TCS) in human spaceflight vehicles, such as variable geometry spacecraft radiator. The TCS in crewed vehicles must maintain a relatively constant environment temperature for a wide range of external thermal environments (low earth orbit, trans-planetary coast, and planetary surface operations). The sink temperature may vary from approximately 70 K to 230 K.</p><p style="margin-left:0in; margin-right:0in">Recent researches investigated and presented potential of heat rejection capability from the morphing composite / shape memory alloys (SMA) radiator. The SMA radiator employs such temperature dependent SMA materials to passively morph the radiator shape and thus adjust the rate of heat rejection to a wide range of vehicle requirements. Nonetheless, utilizing SMA materials faces many disadvantages, including low actuation frequency, sensitivity of material properties in fabrication, residual stress&rsquo;s developed in thin films, and nonlinearity of actuation force.</p><p style="margin-left:0in; margin-right:0in">Advanced Cooling Technologies, Inc. (ACT) proposes to develop a novel vapor-pressure-driven variable view factor radiator as a thermal control system component for spacecraft. Similar to SMA radiator mechanism, the radiator folds into a tear drop shape to minimize the view factor when cold, and opens up to maximize the view factor when heated. However, the proposed device instead utilizes vapor pressure inside a hollow curved panel to change the shape of the radiator. In Phase I, a proof-of-concept two-phase vapor pressure driven morphing radiator prototype will be fabricated and tested. Test results will be used to validate a thermo-structural model, which will be employed to design the full-scale prototype.</p>