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수치해석을 통한 에너지 파일의 장기 운용에 따른 지반의 온도변화 분석

Analysis on Temperature Change of Ground by Long-term Performance of Energy Pile

  • 김범준 (강릉원주대학교 토목공학과) ;
  • 윤찬영 (강릉원주대학교 토목공학과)
  • 투고 : 2019.07.04
  • 심사 : 2019.09.09
  • 발행 : 2019.10.31

초록

본 연구에서는 에너지 파일의 장기적인 운용이 지반의 온도변화에 미치는 영향을 확인하기 위해, 에너지 파일이 설치된 지반을 모사하고 유한요소해석을 수행하였다. 해석은 간헐적 냉방조건(8시간 운용, 16시간 정지)에서 에너지 파일 내부에 설치된 열순환 파이프의 외경에서부터 파일 표면까지의 이격거리를 변화시켜가면서 수행하였다. 해석결과, 에너지 파일의 간헐적 냉방운용 조건에서의 장기적인 열교환은 지반 내부의 열적 회복력을 감소시키고, 잔류열에너지를 유발하여 주변지반의 온도를 증가시키는 것으로 나타났다. 또한 주변지반의 온도는 에너지 파일에 가까워질수록 더 높은 온도를 갖는 것으로 나타나며, 열순환 파이프 외측 콘크리트 말뚝의 표면간의 거리가 줄어들수록 온도는 더욱 증가하는 것으로 나타났다.

In this study, to investigate the effect of long-term performance of energy pile on ground temperature, a numerical analysis was conducted by simulating the ground where an energy pile was installed. In the analysis, a changing distance from the outer perimeter of a heat circulation pipe to the surface of concrete pile for an intermittent operation (8-hour operation, 16-hour stop) was considered. Simulation results showed that long-term heat exchange under the intermittent operation of energy pile reduced a thermal recovery in the ground and increased the ground temperature through the residual thermal energy. In addition, the ground temperature became higher as it got closer to the energy pile and increased as the distance from the outer perimeter of heat circulation pipe to the surface of concrete pile decreased.

키워드

참고문헌

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