Shock and Vibration Tolerant Capillary Two-Phase Loops

Advanced Cooling Technologies, Inc. (ACT), supported by Hamilton Sundstrand, proposes to develop a shock and vibration tolerant Capillary Two-Phase Loop (CTPL) for military vehicle applications. The proposed CTPL differs from the traditional loop heat pipes and capillary pumped loops in the evaporator design, which provides inherent tolerance to shock and vibration. Two additional features are added to further improve the shock and vibration tolerance: (1) graded wicks are used in the evaporator to mitigate the shock and vibration impact on the liquid-vapor interface (meniscus); and (2) check valves are used in the liquid transport line to mitigate the macro-scale liquid churning motion. The Phase I project successfully verified the basic concept of the shock/vibration tolerant CTPL technology through proof-of-concept CTPL design, fabrication and testing. The Phase II project will design, fabricate and test full scale CTPLs under representative Mil-Spec shock and vibration conditions. The follow on Phase III project will integrate the technology in actual vehicles and conduct qualification tests in simulated operational environments.