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2020 Vol.14, Issue 2

Research Article

Equivalent Thermal Model for Ground Heat Exchangers Considering Ground Temperature Recovery

지중 복원력을 고려한 지중 열교환기 등가 열해석 모델

Seung Hyo Baek1*
백 승효1*
1Assistant Professor, Division of Architecture, Mokwon University
1목원대학교 건축학부 조교수
* Corresponding Author
30 April 2020. pp. 147-157
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Abstract

Ground temperature recovery has a considerable impact on the performance of ground heat exchangers and ground-coupled heat pump systems. Some studies have found that consideration of ground temperature recovery in the design of ground heat exchangers allows for a reduction in the size thereof. Based on this finding, this study first investigates whether previous design methods and thermal analysis models for ground heat exchangers are appropriate for the design considering ground temperature recovery. We find that assumptions regarding heat extraction made in previous design methods make it difficult to consider ground temperature recovery. Simplified thermal analysis models for ground heat exchangers are also required to support the design. For these purposes, this study proposes an equivalent thermal analysis model for ground heat exchangers. This model is validated against measurement data of a sand-box test, and validation results demonstrate good agreement. We expect that the proposed model contributes to proposing design methods considering ground temperature recovery.

Keywords
Ground-coupled heat pump
Ground heat exchangers
Ground temperature recovery
Design
Transient thermal analysis model

키워드
지열 히트펌프
지중 열교환기
지중 복원력
설계
동적 열해석 모델
References
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Information
  • Publisher :Korean Institute of Architectural Sustainable Environment and Building Systems
  • Publisher(Ko) :한국건축친환경설비학회
  • Journal Title :Journal of Korean Institute of Architectural Sustainable Environment and Building Systems
  • Journal Title(Ko) :한국건축친환경설비학회논문집
  • Volume : 14
  • No :2
  • Pages :147-157
  • Received Date : 2019-05-19
  • Revised Date : 2020-04-17
  • Accepted Date : 2020-04-19
  • DOI :https://doi.org/10.22696/jkiaebs.20200014
Journal Informaiton Journal of Korean Institute of Architectural Sustainable Environment and Building Systems Journal of Korean Institute of Architectural Sustainable Environment and Building Systems
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