Journal of the Korean Solar Energy Society (한국태양에너지학회 논문집)

The Korean Solar Energy Society (한국태양에너지학회)
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Analysis on the Effect of Local Climate on the Unit-type Ground Heat Exchanger

지역 기후가 유닛형 지중열교환기 성능에 미치는 영향

  • Bae, Sangmu (Department of Architectural Engineering, Pusan National University) ;
  • Kim, Jae-Min (Department of Architectural Engineering, Pusan National University) ;
  • Nam, Yujin (Department of Architectural Engineering, Pusan National University)
  • Received : 2019.01.14
  • Accepted : 2019.02.11
  • Published : 2019.02.28
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Abstract

A ground source heat pump (GSHP) system can stable system operation by using underground heat source and has high reliability for energy production. However, wide-spread of the GSHP system is delayed to high initial investment costs. In previous studies, horizontal and unit-type ground heat exchanger (GHX) have developed to overcome disadvantages such as high initial cost. However, these performances of GHXs are greatly influenced by climate and weather conditions. It is necessary to analyze the performance of GHX according to the ground temperature change in the installation site. In this study, the ground temperature of each installation site confirmed and performance of unit-type GHX quantitatively analyzed by numerical analysis. As the result, the performance of the unit type GHX was 33.9 W/m in Seoul, 34.2 W/m in Daejeon, and 37.2 W/m in Busan.The result showed the difference performance of GHX according to local climate was maximum of 9.7%.

Keywords

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Fig. 1 Schematic diagram of the Unit-type GHX

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Fig. 2 Mechanism of the groundsurface heat flux12)

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Fig. 3 Numerical model of unit-type GHX

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Fig. 4 Underground temperature at depth 1 m and 5 m

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Fig. 5 Daily average HER according to change of EWT

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Fig. 6 Performance of uni-type GHX according to local climate

Table 1 Simulation conditions

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Table 2 Case study condition and average annual outdoor/ground surface temperature

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