Heat Transfer Mechanism of Heat–Cold Alternate Extraction in a Shallow Geothermal Buried Pipe System under Multiple Heat Exchanger Groups

Jianlong Shi, Wei Zhang (), Mingjian Wang, Chunguang Wang, Zhengnan Wei, Dong Wang and Peng Zheng
Additional contact information
Jianlong Shi: College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Wei Zhang: College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Mingjian Wang: College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Chunguang Wang: College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Zhengnan Wei: New-Energy Development Center, Shengli Oilfield of Sinopec, Dongying 257001, China
Dong Wang: New-Energy Development Center, Shengli Oilfield of Sinopec, Dongying 257001, China
Peng Zheng: Qingdao Wofu New Energy Technology Co., Ltd., Qingdao 266100, China

Energies, 2023, vol. 16, issue 24, 1-23

Abstract: Shallow geothermal energy usually uses underground buried pipes to achieve the purpose of extracting heat while storing cold in winter and extracting cold while storing heat in summer. However, the heat transfer mechanism under the alternate operation of heat–cold extraction in winter and summer under multiple heat exchanger groups is still worth studying. Based on the constructed flow and heat transfer model in pipelines and reservoirs, this study first analyzes the temperature field evolution of a shallow buried pipe system (SBPS) under the alternate operation of heat–cold extraction, and then discusses the heat transfer performance under different pipeline flow rates, pipeline wall thermal conductivity, heat injection durations, numbers of heat exchanger groups, and flows of underground fluid. The results show that the continuous alternating process of heat–cold extraction has a promoting effect on the temperature increase or decrease in the next operating cycle due to the low- or high-temperature zone produced in the previous operating cycle. As the number of multiple heat exchanger groups increases, the heat transfer efficiency of the SBPS significantly improves. With a rise in the groundwater flow velocity, the heat transfer efficiency first decreases and then increases.

Keywords: shallow buried pipe system; shallow geothermal system; heat transfer mechanism; heat–cold alternate extraction; multiple heat exchanger groups (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2023
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/16/24/8067/pdf (application/pdf)
https://www.mdpi.com/1996-1073/16/24/8067/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:16:y:2023:i:24:p:8067-:d:1300244

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().