Condensing Heat Exchanger for Space Systems: Laser Processed [CHESS-LP]

Goal: To repurpose an existing plate-fin heat exchanger for proof-of-concept integration of a capillary-driven test section made from microbial-resistant surface etching. Capability Need/Knowledge Gap: The objective of this work is to repurpose an existing heat exchanger with a new test section to demonstrate improved resistance against biofouling of the system, leading to extended life of system components with less required maintenance. Heat exchangers suffer from continual microbial growth issues and a dependence on surface film coatings. Constructing the test section from laser-processed silver sheets based on established research will further improve the reliability and resistance to contaminants. State-of-the-Art/Knowledge: Condensing Heat Exchangers are an integral part of air conditioning and humidity/environmental control on Earth and in space. On ISS, the existing ECLSS heat exchanger’s continued chemical degradation has reduced system performance. Key Technical Challenges: Identifying components of the existing heat exchanger in lab for reutilization; manufacturing system components based on new laser processing methods; and, integrating a capillary-based flow path with the new system. Approach/Research Plan: (1) Determine original CHESS hardware usage; (2) Manufacture laser-processed components; (3) Integrate and test; and, (4) Baseline data assessment and proof of concept analysis. An existing heat exchanger unit will be used as the foundation for new research. Next Step: Further research in this field could involve the impact of siloxanes that are produced by the water recovery unit. Siloxanes can become trapped inside the ISS heat exchanger and precipitate out from the water, causing blockage and leading to microbial growth in some areas, in addition to corrosion of the hardware.

With continued presence in low Earth orbit (LEO) and eventual plans to reach the Moon and Mars, there is a critical need for microgravity-compatible life support systems that can last beyond current system lifetimes. NASA requires long-term, reliable, environmental control and life support systems (ECLSS) with minimal astronaut intervention. Knowledge of fluid behavior in microgravity and low-g environments is essential to using capillary forces and surface tension to replace the role of gravity. Using interior corners for liquid control and surface etching for wetting behavior adds in several methods of passive fluid containment. Recent advances in microgravity fluids have shown the “cross-pollination” potential for applications of these designs. Although they are developed though fluid physic research, they have applications in plant growth, water reclamation, and heat exchangers, to name a few.

This is a mature technology (TRL 7+) — the realistic path in is usually NASA's Technology Transfer Program: licensing an existing NASA patent, or a Space Act Agreement to use NASA facilities/expertise directly. NASA also runs a startup licensing program with no upfront fee for companies formed to commercialize a specific NASA technology.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.