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2013 Vol.29, Issue 9 Preview Page
Prediction of Heat Exchange Rate in PHC Energy Piles

PHC 에너지 파일의 열교환율 예측에 관한 연구

Seok Yoon1
,
Seung-Rae Lee2
,
Hyun-Ku Park3
,
Do-Won Park4
,
Gyu-Hyun Go5
윤 석1
,
이 승래2
,
박 현구3
,
박 도원4
,
고 규현5
1Graduate Student, Dept. of Civil and Environmental Eng., KAIST
2Prof., Dept. of Civil and Environmental Eng., KAIST
3Assitant Manager, Civil and Infrastructure Business Unit, Samsung C&T Corporation
4Graduate Student, Dept. of Civil and Environmental Eng., KAIST
5Graduate Student, Dept. of Civil and Environmental Eng., KAIST
1KAIST 건설및환경공학과 박사과정
2KAIST 건설및환경공학과 교수
3삼성물산 건설부분 토목 사업부 대리
4KAIST 건설및환경공학과 석사과정
5KAIST 건설및환경공학과 박사과정
교신저자. Corresponding Author. 
30 September 2013. pp. 31-41
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Abstract

The use of energy pile foundation has increased for economic utilization of geothermal energy. In particular, coil-shaped ground heat exchanger (GHE) is preferred to the conventional U-shaped exchanger to ensure better efficiency of heat exchange rate. This paper presents a numerical and experimental study on the heat transfer behavior of PHC energy piles. Field thermal performance tests (TPTs) were conducted for the PHC energy piles installed in a partially saturated weathered granite soil deposit, in which two types of GHEs were considered: W and coil shaped GHEs. Besides, three-dimensional finite element analyses were also conducted, and the results were compared with the experimental results. According to the results of TPT and numerical analyses, the coil shaped GHE showed 10～15% higher heat exchange rate than the W type GHE in the PHC energy piles.

Keywords
Energy piles
Thermal performance test
Numerical analysis
Heat exchange rate

최근 들어 경제적인 지열에너지 활용을 위하여 에너지 파일의 적용이 확대되고 있다. 특히 더 높은 열 교환 효율을 확보하고자 에너지 파일의 경우 보다 높은 열효율을 얻기 위해 통상적인 U자형 지중 열교환기가 아닌 코일형 지중 열교환기를 매입하는 경우가 늘어나고 있다. 본 논문에서는 PHC 에너지 파일에 의한 지중 열 전달 거동에 대한 수치해석 및 실험적 연구를 수행하였다. 화강풍화토로 이루어진 현장에 PHC 에너지 파일을 설치하고 W자형과 코일형 지중 열교환기를 설치한 후 이에 대한 현장 열성능 실험을 수행하였다. 또한 3차원 유한요소해석을 수행하여 지중 온도 및 지중 열교환기 내 순환수 온도 변화를 예측하였고 이를 실험값과 비교하였다. 냉방 부분 가동 조건 하에서 코일형 열교환기 이용시 W자형을 이용했을 때보다 10～15% 열교환율이 상승되는 것을 알 수 있었다.

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Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 29
  • No :9
  • Pages :31-41
  • Received Date : 2013-01-27
  • Revised Date : 2013-06-23
  • Accepted Date : 2013-09-12
  • DOI :https://doi.org/10.7843/kgs.2013.29.9.31
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