Comparative study of heat transfer enhancement using different fins in semi-circular absorber tube for large-aperture trough solar concentrator

RENEWABLE ENERGY

卷:169

Article

Gong, Jing-hu^1,2  Wang, Jun^1,2  Lund, Peter D.^1,3  Zhao, Dan-dan^1,2  Xu, Jing-wen^1,2  Jin, Yi-hao^1,2 

[1] Southeast Univ, Key Lab Solar Energy Sci & Technol Jiangsu Prov, Nanjing 210096, Peoples R China

[2] Southeast Univ, Sch Energy & Environm, Nanjing 210096, Peoples R China

[3] Aalto Univ, Sch Sci, FI-00076 Aalto, Espoo, Finland

关键词: Large-aperture parabolic trough concentrator;    Semi-circular absorber tube;    Flat-plate radiation shield;    Fin;    Heat transfer;   

DOI  :  10.1016/j.renene.2020.12.054

来源: Elsevier

【 摘 要 】

An improved evacuated absorber tube (AT) design consisting of a semi-circular tube is proposed for large-aperture parabolic trough concentrator. The absorber tube also contains a flat-plate radiation shield in the vacuum part of the tube in the glass cover. To enhance the heat transfer in the AT, different fins geometries added to the bottom of the AT were analyzed here. Compared to an AT without fins, the thermal efficiency of the tube could be increased from 75.7% to 76.9% with a short and thick fin and to 77.3% with a long and thin fin in the flow velocity range of 0.4-1.5 m/s. The long and thin finned AT shows better enhancement of heat transfer, but the heat transfer performance factor also accounting for frictional losses is higher for short and thick fin. Simultaneously, increasing the number of long and thin fins in the AT would not improve much the heat transfer performance. (C) 2020 Elsevier Ltd. All rights reserved.

【 授权许可】

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