文献类型：期刊文献

英文题名：Thermo-Hydraulic Performance of U-Tube Borehole Heat Exchanger with Different Cross-Sections

作者：Zhou, Aizhao[1];Huang, Xianwen[1,2];Wang, Wei[3];Jiang, Pengming[1];Li, Xinwei[1,2]

机构：[1]Jiangsu Univ Sci & Technol, Sch Civil & Architecture Engn, Zhenjiang 212003, Jiangsu, Peoples R China;[2]Anhui Univ Sci & Technol, Sch Architecture & Civil Engn, Huainan 232000, Peoples R China;[3]Shaoxing Univ, Sch Civil Engn, Shaoxing 312000, Peoples R China

年份：2021

卷号：13

期号：6

外文期刊名：SUSTAINABILITY

收录：SSCI(收录号：WOS:000645768500001)、SCI-EXPANDED(收录号：WOS:000645768500001)、、Scopus(收录号：2-s2.0-85103384954)、WOS

基金：This research was funded by the National Natural Science Foundation of China grant numbers 51579119 and 41772311. The APC was funded by A.Z.

语种：英文

外文关键词：ground source heat pump; borehole heat exchange; single U-shape; tube shape; heat resistance

外文摘要：For reducing the initial GSHP investment, the heat transfer efficiency of the borehole heat exchange (BHE) system can be enhanced to reduce the number or depth of drilling. This paper proposes a novel and simple BHE design by changing the cross-sectional shape of the U-tube to increase the heat transfer efficiency of BHEs. Specifically, in this study, we (1) verified the reliability of the three-dimensional numerical model based on the thermal response test (TRT) and (2) compared the inlet and outlet temperatures of the different U-tubes at 48 h under the premise of constant leg distance and fluid area. Referent to the circular tube, the increases in the heat exchange efficiencies of the curved oval tube, flat oval tube, semicircle tube, and sector tube were 13.0%, 19.1%, 9.4%, and 14.8%, respectively. (3) The heat flux heterogeneity of the tubes on the inlet and outlet sides of the BHE, in decreasing order, is flat oval, semicircle, curved oval, sector, and circle shapes. (4) The temperature heterogeneity of the borehole wall in the BHE in decreasing order is circle, sector, curved oval, flat oval, and semicircle shapes. (5) Under the premise of maximum leg distance, referent to the heat resistance of the tube with a circle shape at 48 h, the heat exchange efficiency of the curved oval, flat oval, semicircle, and sector tubes increased 12.6%, 17.7%, 10.3%, and 7.8%, respectively. (6) We found that the adjustments of the leg distance and the tube shape affect the heat resistance by about 25% and 12%, respectively. (7) The flat-oval-shaped tube at the maximum leg distance was found to be the best tube design for BHEs.