Evaluation on in-situ Heat Exchange Efficiency of Energy Slab According to Pipe Materials and Configurations

파이프 재질 및 형태에 따른 에너지 슬래브의 현장 열교환 성능 평가

  • Lee, Seokjae (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Oh, Kwanggeun (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Han, Shin-in (R&D Center, Seoyoung Engineering) ;
  • Park, Sangwoo (Department of Civil Engineering and Environment, Korea military academy) ;
  • Choi, Hangseok (School of Civil, Environmental and Architectural Engineering, Korea University)
  • 이석재 (고려대학교 건축사회환경공학부) ;
  • 오광근 (고려대학교 건축사회환경공학부) ;
  • 한신인 ((주)서영엔지니어링) ;
  • 박상우 (육군사관학교 토목환경과) ;
  • 최항석 (고려대학교 건축사회환경공학부)
  • Received : 2017.08.14
  • Accepted : 2017.10.31
  • Published : 2017.12.01


The energy slab is a ground coupled heat exchanger equipped in building slab structures, which represents a layout similar to the horizontal ground heat exchanger (GHEX). The energy slab is installed as one component of the floor slab layers in order to utilize the underground structure as a hybrid energy structure. However, as the energy slab is horizontally arranged, its thermal performance is inevitably less than the conventional vertical GHEXs. Therefore, stainless steel (STS) pipes are alternatively considered as a heat exchanger instead of high density polyethylene (HDPE) pipes in order to enhance thermal performance of GHEXs. Moreover, not only a floor slab but also a wall slab can be utilized as a heat-exchangeable energy slab in order to maximize the use of underground space effectively. In this paper, four field-scale energy slabs were constructed in a test bed, which consist of the STS and HDPE pipe, and a series of thermal response tests (TRTs) was conducted to evaluate relative heat exchange efficiency per unit pipe length according to the pipe material and the configuration of energy slabs. The energy slab equipped with the STS pipe shows higher thermal performance than the energy slab with the HDPE pipe. In addition, thermal performance of the wall-type energy slab is almost equivalent to the floor-type energy slab.



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