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DOE OSTI · 3007982

Low-cost and high-performance heat exchangers for CSP

Zhao, Ji-Cheng [Univ. of Maryland, College Park, MD (United States)] (ORCID:0000000244261080)·Shooshtari, Amir H. [Univ. of Maryland, College Park, MD (United States)]·Young, Nathan Jay [Univ. of Maryland, College Park, MD (United States)]·Garnett, Jessica Annabel [Univ. of Maryland, College Park, MD (United States)]
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Abstract

This project aimed to design and manufacture a low-cost and high-performance, particle–to–sCO 2 heat exchanger (HX) for Concentrated Solar Power (CSP) using additive manufacturing (AM). Three enabling technologies will be integrated to achieve the targeted cost and performance. The first technology is the extreme high‐speed laser materials deposition (LMD) AM process known by its German acronym EHLA that was invented at the Fraunhofer Institute for Laser Technology. The EHLA process utilizes a specially designed powder-feeding nozzle that enables a laser to melt the powder particles above the melt pool, in contrast to the conventional LMD process where the powders are melted inside the melt pool. EHLA enables much faster deposition rate than conventional LMD without the need to wait for the powders to melt. The second technology is an innovative double-helical HX geometry that can be easily fabricated using the EHLA process by rotating a rod at a high-speed to take advantage of the high EHLA deposition rate. The double-helical fins separate the hot region (the hot particle side) and the cold region (the sCO 2 side) and provide large heat transfer surface area without a large pressure drop on the sCO 2 side. The particle side will have a larger gap to facilitate the particle flow. The outer rims of the double helixes can be sealed off using the same AM process. After sealing-off, additional double helixes can be built radially on top of the first set to improve HX performance. The HX can be installed vertically for gravity-driven flow of the hot particles if necessary. The third technology is a low-cost high-temperature alumina-forming austenitic (AFA) steel TMA-6350 that has creep and oxidation resistance up to 1100 °C. These technologies together will enable high-performance and low-cost HXs for particle–to–sCO 2 for CSP.

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14 SOLAR ENERGY36 MATERIALS SCIENCE42 ENGINEERINGadditive manufacturingconcentrated solar powerheat exchangersparticle-to-supercritical CO2 heat transfersupercritical carbon dioxide

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Zhao, Ji-Cheng [Univ. of Maryland, College Park, MD (United States)] (ORCID:0000000244261080), Shooshtari, Amir H. [Univ. of Maryland, College Park, MD (United States)], Young, Nathan Jay [Univ. of Maryland, College Park, MD (United States)], Garnett, Jessica Annabel [Univ. of Maryland, College Park, MD (United States)]. 2025-06-12. Low-cost and high-performance heat exchangers for CSP. https://doi.org/10.2172/3007982

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