Framework for Design, Modelling, and Qualification of Phase Change Material Heat Sinks for Small Satellites
Session
Frank J. Redd Student Competition
Location
Salt Palace Convention Center, Salt Lake City, UT
Abstract
The increasing use of high-power hardware in small satellites presents a critical thermal management challenge. Phase Change Material (PCM) heat sinks provide passive thermal control for transient heat loads by storing thermal energy as latent heat during melting, maintaining near-constant temperatures. This creates a thermal buffer that lowers peak heat fluxes and reduces the required radiative surface area. A PCM heatsink was required for thermal control of a payload on an upcoming mission at the Space Flight Laboratory (SFL). This motivated the development of in-house PCM capabilities to enable mission-specific designs at lower cost and shorter schedules. This paper presents a framework to design, model, experimentally validate, and qualify PCM heat sinks for small satellites. A simplified thermal modelling approach is presented and experimentally validated, demonstrating that PCM thermal behavior can be accurately captured without reliance on computational fluid dynamics (CFD). Two hardware iterations illustrate this framework: an exploratory prototype using n-octadecane for a 50 W optical terminal with a 35°C temperature limit, and a qualification model (QM) using n-docosane for a 36 W transmitter and 50°C operational limit. A plate-fin geometry with a 30% filler volume fraction was selected through trade studies to optimize peak temperature, mass, and manufacturability. Transient thermal testing in vacuum confirmed that the thermal model pre-dictions are within 0.5°C. Testing in multiple orientations bounded the expected microgravity performance to a variation of 0.6°C, and confirmed the suppression of buoyancy-driven convection in ground testing. The QM was qualified to SpaceX Rideshare pressurized hardware standards which involved helium leak, proof and burst pressure testing (demonstrated burst factor of 7.3). Vibration testing verified structural integrity under an 18.2 grms random vibration profile, and confirmed that the natural frequencies do not couple with the spacecraft structure. This framework establishes a practical and repeatable approach for small satellite teams to develop lower-cost, mission-specific PCM thermal control solutions for high-power hardware.
Document Type
Event
Framework for Design, Modelling, and Qualification of Phase Change Material Heat Sinks for Small Satellites
Salt Palace Convention Center, Salt Lake City, UT
The increasing use of high-power hardware in small satellites presents a critical thermal management challenge. Phase Change Material (PCM) heat sinks provide passive thermal control for transient heat loads by storing thermal energy as latent heat during melting, maintaining near-constant temperatures. This creates a thermal buffer that lowers peak heat fluxes and reduces the required radiative surface area. A PCM heatsink was required for thermal control of a payload on an upcoming mission at the Space Flight Laboratory (SFL). This motivated the development of in-house PCM capabilities to enable mission-specific designs at lower cost and shorter schedules. This paper presents a framework to design, model, experimentally validate, and qualify PCM heat sinks for small satellites. A simplified thermal modelling approach is presented and experimentally validated, demonstrating that PCM thermal behavior can be accurately captured without reliance on computational fluid dynamics (CFD). Two hardware iterations illustrate this framework: an exploratory prototype using n-octadecane for a 50 W optical terminal with a 35°C temperature limit, and a qualification model (QM) using n-docosane for a 36 W transmitter and 50°C operational limit. A plate-fin geometry with a 30% filler volume fraction was selected through trade studies to optimize peak temperature, mass, and manufacturability. Transient thermal testing in vacuum confirmed that the thermal model pre-dictions are within 0.5°C. Testing in multiple orientations bounded the expected microgravity performance to a variation of 0.6°C, and confirmed the suppression of buoyancy-driven convection in ground testing. The QM was qualified to SpaceX Rideshare pressurized hardware standards which involved helium leak, proof and burst pressure testing (demonstrated burst factor of 7.3). Vibration testing verified structural integrity under an 18.2 grms random vibration profile, and confirmed that the natural frequencies do not couple with the spacecraft structure. This framework establishes a practical and repeatable approach for small satellite teams to develop lower-cost, mission-specific PCM thermal control solutions for high-power hardware.
