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Comparative Study of the Thermal and Hydraulic Performance of Supercritical CO(2) and Water in Microchannels Based on Entropy Generation

The excellent thermophysical properties of supercritical CO(2) (sCO(2)) close to the pseudocritical point make it possible to replace water as the coolant of microchannels in application of a high heat flux radiator. The computational fluid dynamics (CFD) method verified by experimental data is used...

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Autores principales: Tu, Yi, Zeng, Yu
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9498290/
https://www.ncbi.nlm.nih.gov/pubmed/36141198
http://dx.doi.org/10.3390/e24091312
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author Tu, Yi
Zeng, Yu
author_facet Tu, Yi
Zeng, Yu
author_sort Tu, Yi
collection PubMed
description The excellent thermophysical properties of supercritical CO(2) (sCO(2)) close to the pseudocritical point make it possible to replace water as the coolant of microchannels in application of a high heat flux radiator. The computational fluid dynamics (CFD) method verified by experimental data is used to make a comparison of the thermal hydraulic behavior in CO(2)-cooled and of water-cooled microchannels. The operation conditions of the CO(2)-based cooling cases cover the pseudocritical point (with the inlet temperature range of 306~320 K and the working pressure of 8 MPa), and the water-based cooling case has an inlet temperature of 308 K at the working pressure of 0.1 MPa. The channel types include the straight and zigzag microchannels with 90°, 120°, and 150° bending angles, respectively. The analysis result shows that, only when the state of CO(2) is close to the pseudocritical point, the sCO(2)-cooled microchannel is of a higher average heat convection coefficient and a lower average temperature of the heated surface compared to the water-cooled microchannel. The entropy generation rate of the sCO(2)-cooled microchannel can reach 0.58~0.69 times that of the entropy generation rate for the water-cooled microchannel. Adopting the zigzag structure can enhance the heat transfer, but it does not improve the comprehensive performance represented by the entropy generation rate in the sCO(2)-cooled microchannel.
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spelling pubmed-94982902022-09-23 Comparative Study of the Thermal and Hydraulic Performance of Supercritical CO(2) and Water in Microchannels Based on Entropy Generation Tu, Yi Zeng, Yu Entropy (Basel) Article The excellent thermophysical properties of supercritical CO(2) (sCO(2)) close to the pseudocritical point make it possible to replace water as the coolant of microchannels in application of a high heat flux radiator. The computational fluid dynamics (CFD) method verified by experimental data is used to make a comparison of the thermal hydraulic behavior in CO(2)-cooled and of water-cooled microchannels. The operation conditions of the CO(2)-based cooling cases cover the pseudocritical point (with the inlet temperature range of 306~320 K and the working pressure of 8 MPa), and the water-based cooling case has an inlet temperature of 308 K at the working pressure of 0.1 MPa. The channel types include the straight and zigzag microchannels with 90°, 120°, and 150° bending angles, respectively. The analysis result shows that, only when the state of CO(2) is close to the pseudocritical point, the sCO(2)-cooled microchannel is of a higher average heat convection coefficient and a lower average temperature of the heated surface compared to the water-cooled microchannel. The entropy generation rate of the sCO(2)-cooled microchannel can reach 0.58~0.69 times that of the entropy generation rate for the water-cooled microchannel. Adopting the zigzag structure can enhance the heat transfer, but it does not improve the comprehensive performance represented by the entropy generation rate in the sCO(2)-cooled microchannel. MDPI 2022-09-16 /pmc/articles/PMC9498290/ /pubmed/36141198 http://dx.doi.org/10.3390/e24091312 Text en © 2022 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Tu, Yi
Zeng, Yu
Comparative Study of the Thermal and Hydraulic Performance of Supercritical CO(2) and Water in Microchannels Based on Entropy Generation
title Comparative Study of the Thermal and Hydraulic Performance of Supercritical CO(2) and Water in Microchannels Based on Entropy Generation
title_full Comparative Study of the Thermal and Hydraulic Performance of Supercritical CO(2) and Water in Microchannels Based on Entropy Generation
title_fullStr Comparative Study of the Thermal and Hydraulic Performance of Supercritical CO(2) and Water in Microchannels Based on Entropy Generation
title_full_unstemmed Comparative Study of the Thermal and Hydraulic Performance of Supercritical CO(2) and Water in Microchannels Based on Entropy Generation
title_short Comparative Study of the Thermal and Hydraulic Performance of Supercritical CO(2) and Water in Microchannels Based on Entropy Generation
title_sort comparative study of the thermal and hydraulic performance of supercritical co(2) and water in microchannels based on entropy generation
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9498290/
https://www.ncbi.nlm.nih.gov/pubmed/36141198
http://dx.doi.org/10.3390/e24091312
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