Development of a Thermal Radiator Optimization Tool with Alternate Coolants

Greg Schunk

NASA NTRS · 20260007746

Development of a Thermal Radiator Optimization Tool with Alternate Coolants

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Abstract

The development of a modeling tool to optimize the design of a thermal radiator based on capacity, rejection temperature, geometry, type and coolant is presented. The radiator size is determined from the desired capacity, environmental conditions and rejection temperature. Flow through the radiator is derived from the overall heat load and prescribed inlet to outlet delta temperature for a given coolant. The tool considers radiator geometry (i.e., tube spacing and diameter, face-sheet thickness, overall size, etc.) and general type (i.e., parallel/manifold versus serpentine) in the optimization. Selection from a handful of potential coolants is also available in the tool which primarily affects necessary tube diameter to maintain turbulent flow and minimize pressure drop. An Equivalent System Mass (ESM) approach is utilized to include pump power in the optimization. Results from the tool and potential future enhancements are also discussed.

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Coolant Radiator Thermal Spacecraft

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Greg Schunk. Development of a Thermal Radiator Optimization Tool with Alternate Coolants. https://ntrs.nasa.gov/citations/20260007746

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