Advanced Two-Phase Cooling System for Modular Power Electronics

NASA envisions building future space power system architectures with many standardized, interchangeable, and reusable modular electronics to improve system adaptability and minimize the cost of development, operation, and maintenance. As the size of the electronics becomes smaller, future high-performance electronic modules will generate higher waste heat fluxes, which will be unmanageable by the current state-of-art cooling systems. More effective heat transfer devices and integrated cooling systems that can significantly reduce the overall thermal resistance from the semiconductors to the heat sink are highly desired. Under an SBIR program, Advanced Cooling Technologies, Inc. (ACT) developed a lightweight and effective cooling system for 3U modular electronics in a common enclosure. The system consists of multiple advanced thermal management components, including two-phase heat spreaders to move the heat from card center to edges and enhanced card locks to minimize card-to-chassis thermal resistance. Two types of two-phase solutions were identified and investigated. The first one is heat pipe embedded card (i.e. Hi-KTM plate) and the second is pulsating heat pipe (PHP) plate. ACT designed, fabricated, and thermally tested on a lab-scale mock modular electronics system. A comprehensive trade study and the overall improvement in heat transfer by these two heat spreaders in comparison to an aluminum plate were discussed.