Hybrid Thermal Control System for Extreme Thermal Environments



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2023 International Conference on Environmental Systems


NASA's return to the moon brings about many challenges, including issues with survival on the Lunar surface. In order to be sustainable, assets such as landers, rovers, and habitats must be usable for more than a single mission duration. One of the key challenges with sustainability is designing adequate thermal control systems that allow for surface systems to survive both during the day and the Lunar Night. Marshall Space Flight Center (MSFC) has been developing a hybrid thermal control system that can be utilized for various surface assets that must survive in extreme lunar environments. This scalable system is targeted for human-rated systems and utilizes a combination of a pumped fluid loop (PFL) and a loop heat pipe (LHP) with thermal control valve (TCV). Pumped fluid loops have a long history of use in human rated systems. They can collect large amounts of waste heat and transport it over long distances in rovers, habitats, and other systems. By utilizing a non-toxic working fluid in the habitable volume the PFL is easily serviceable by the crew and does not pose a risk during any unexpected leaks or failures. The addition of a LHP for the exterior heat transport and rejection adds several benefits to the system for extreme environment survival. The quantity of LHPs can be tailored to optimize heat rejection for different systems and allows for large radiative surfaces. By utilizing a TCV in combination with the LHP, there can be high heat transfer during the daytime with minimal heat transfer during the night. The TCV passively controls the amount of heat transfer through the LHP based on the environmental tempera-ture. A prototype system has been tested in benchtop and thermal vacuum conditions. Results are presented showing the turndown ratio and power consumption compared to a traditional systems.


William Johnson, NASA Marshall Space Flight Center, USA
Kayla Daniel, NASA Marshall Space Flight Center, USA
Kenton Roberts, NASA Marshall Space Flight Center, USA
Greg Schunk, NASA Marshall Space Flight Center, USA
Jeffery Farmer, NASA Marshall Space Flight Center, USA
ICES103: Thermal Control of Commercial and Exploration Spacecraft
The 52nd International Conference on Environmental Systems was held in Calgary, Canada, on 16 July 2023 through 20 July 2023.


extreme thermal environments, habitat thermal control system, loop heat pipe