Lightweight Passive Vaporizing Heat Sink

This project develops a lightweight passive heat sink that uses a vaporizing coolant for transient thermal control of spacecraft components. Particularly during launch and reentry, there are heat loads in electronics and batteries that require special handling. The Space Shuttle, for example, uses water flash evaporator systems that are, however, complex and unsuited for isolated electronics boxes, batteries, or sample return containers. We propose heat sinks based on innovative wicks and fiber heat exchangers that enable high thermal effectiveness in a lightweight compact package that can be dedicated to individual components. Phase 1 will analyze the concept, survey materials candidates, identify applications requirements, and fabricate test articles to acquire performance data for a range of heat fluxes and total energy. Vaporizing heat sink tests will be performed in vacuum at different gravity orientations. Phase 2 would further develop the concept, designs, and materials, leading to a prototype heat sink for a selected NASA application, such as cooling of a battery or electronics box.