In-Situ Heat Rejection to the Martian Atmosphere

R Gregory Schunk

NASA NTRS · 20260007919

In-Situ Heat Rejection to the Martian Atmosphere

Abstract

In order to provide in-situ heat rejection to the thin Martian atmosphere, approaches relying on forced convection and buoyancy flow are conceptualized. A convective radiator concept utilizing a fan to draw local atmosphere through an expanded metal foam heat exchanger panel is developed. To provide a pumped fluid loop interface, flow tubes are embedded in the heat exchanger panel and heat is transferred from the tubes to the foam via conduction and subsequently convectively to the environment. To forgo the use of a specialized high throughput fan, a concept utilizing a buoyant chimney tower to draw atmospheric flow through a low pressure drop heat exchanger is also considered. Both concepts may best align with moderate- to high-temperature heat loads that provide a significant delta temperature relative to the ambient atmosphere temperature. While eliminating dust accumulation on radiator surfaces, some type of serviceable filtration or screening may be required to prevent accumulation of dust inside the expanded metal foam heat exchanger for both concepts.

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Heat Rejection Buoyancy Forced Convection Martian Mars Radiator Thermal Spacecraft

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R Gregory Schunk. In-Situ Heat Rejection to the Martian Atmosphere. https://ntrs.nasa.gov/citations/20260007919

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Buoyancy subject Mars subject Martian subject Radiator subject Spacecraft subject Thermal subject

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