First Place: Space Technology on Earth Claire Bielski (CEE), Karma Bridgman (ECE), Chengyi Cai (HNZ), and Katherine Piper (CEE)

The CK Innovation Team was awarded first place for their project Space Technology on Earth. Drawing inspiration from NASA-developed cooling systems currently used on satellites and space stations, the team proposed retrofitting existing data centers with two-phase liquid cooling technology that dramatically reduces water and electricity use. Their approach could cut cooling energy consumption by up to 75% and reduce water use by 90%, all within a near-silent operation that offers a scalable, space-grade solution to one of the world’s most pressing sustainability challenges.

The team was awarded top prize, the Sustainable Impact Award, which came with a cash prize sponsored by the Center for Engineering Resilience and Climate Adaptation, a research center at CMU focused on strengthening our infrastructure and communities in the face of climate change.

Background: As JPL tackles ever increasingly complex and difficult missions, thermal management is consistently viewed as a possible bottleneck in mission success. From a probe accessing the interior oceans of Europa or Enceladus, robotic assets surviving extended durations in the permanently shadowed regions of the moon, Venus lander and sub-orbital science, or even Earth science missions seeking smaller and more powerful instruments, the ability to efficiently take in and route heat will be crucial to future mission success. Loop Heat Pipes (LHPs) represent the premier passive thermal transport system for spacecraft, are currently flying on hundreds of missions, including SWOT and TES on EOS/AURA (both JPL integrations), as well as GOES weather satellites and Boeing/Hughes 702 satellites. However, recent very high impact flight hardware failures, significantly high implementation costs and excessively long vendor lead times due to extended hardware procurement cycles involving complex integration of a half dozen precision engineered components (relying on highly sensitive, craftsman-dependent fabrication processes) have led to LHPs being seen as a high-risk component and are now viewed unfavorably by the flight community.

Approach and Results: In Year 1, we built a dedicated testbed for straightforward swapping of loop heat pipe evaporators. It enables keeping a single adiabatic and condenser length, as well as simplifying calculations for fill factors and performing charging. Acetone was chosen as our test working fluid due to its low operational pressure, low risk of health and safety implications, and relatively high latent heat. An overall design optimized for simplicity of printing, and not thermal performance, has been created and fabricated. Testing has been performed with startup, operation, and repeatability having been demonstrated by the end of fiscal year with a single-piece aluminum evaporator. In Year 2 we fabricated & tested a number of test geometries. Much of this work was performed by Katherine Piper, an exceptional undergraduate from Caltech. Starting in the summer of 2024, Takeshi Yokouchi, a graduate student from Tohoku University also joined the project team for six months. During the year, we performed a series of thermal tests across a handful of aluminum and titanium evaporator models and porous geometries. These were all performed in a gravity-favorable orientation, similar to how they would be integrated on a planetary science lander such as a distributed lunar seismological network or CLPS lander. Performance was found to exceed state of the art for published systems from both academia & industry, with cost-per-evaporator being less than $5k each compared to $500k for state of the practice systems. Lead time was decreased to a month from a year, and repeatability of performance across multiple builds was demonstrated within experimental uncertainty. Aluminum evaporators were found to suffer significantly from heat leaks across the wick, so a modified geometry was developed. Titanium had less heat leak, and showed superb operation. Inconel 625 variants were received at the end of the FY and will begin testing soon. A design integrating a secondary wick for microgravity (or counter-gravity) operation has also been developed. This FY’s work has led to two NTRs in preparation, as well as two papers.