Experimental Comparison of Two-Phase Heat Spreaders for Space Modular Electronics

Standardized form factor electronics cards promote inter-operability across various applications on land and in space. However, current cards might be less reliable due to thermal management bottlenecks. Conventional approaches for cooling electronics cards involve using conduction based thermal heat spreaders, which are limited in performance. So, to improve thermal management of these electronics, high thermal performing, two-phase based heat spreaders are gaining attention. Among these two-phase heat spreaders, embedded heat pipe has achieved high maturity, while, pulsating heat pipes (PHPs) are in nascent stages. In an ongoing SBIR Phase II program funded by NASA, Advanced Cooling Technologies, Inc. is developing a PHP heat spreader for standard 3U form factor electronics thermal management. A prototype PHP was fabricated by 3D printing approach with aluminum as the base plate. Performance of the PHP was determined and compared to a HiK� plate, which is a copper-water embedded heat pipe heat spreader of same form factor. The experiments were performed on an assembled platform with one central evaporator and two edge condenser configurations. The evaporator was a 1-inch x 1-inch aluminum block with two cartridge heater inserts. A copper tube pressed aluminum cold plate was used as the condenser. Influence of operating parameters such as operating temperature and orientation were determined.