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DOE OSTI · 3024577

SHOTEAM: Superalloy Heat exchangers Optimized for Temperature Extremes and Additive Manufacturability (Final Technical Report)

Fisher, Timothy S. [Univ. of California, Los Angeles, CA (United States)] (ORCID:000000028909313X)
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Abstract

UCLA developed an extreme-condition heat exchanger technology targeted to ultra-high efficiency hybrid aviation power cycles. The heat exchanger targeted operation at 50 kW (thermal) at supercritical CO 2 pressures of 80 and 250 bar (1160 and 3626 psi) in hot and cold streams, respectively and at a hot-stream inlet temperature of 800°C (1472°F). A metallic superalloy capable of withstanding high temperature and pressure was used to fabricate a microtube shell-and-tube-based design supplemented with 3D-printed tube augmentations. The optimized design enhanced overall heat transfer while maintaining a small overall form factor and low weight. This class of heat exchanger could dramatically improve efficiency, power density, and cost effectiveness for new hybrid aviation power cycles, thus enabling economically feasible routes to air vehicle propulsion with substantially less CO 2 emissions to the environment.

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32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION42 ENGINEERINGheat exchangerssupercritical carbon dioxide

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Fisher, Timothy S. [Univ. of California, Los Angeles, CA (United States)] (ORCID:000000028909313X). 2025-12-22. SHOTEAM: Superalloy Heat exchangers Optimized for Temperature Extremes and Additive Manufacturability (Final Technical Report). https://doi.org/10.2172/3024577

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