Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Thermo-hydraulic Numerical Analysis for the Leakage of Buried District Heating Pipe

열수송관의 누수에 대한 열-수리적 수치해석

  • Shin, Hosung (Dept. of Civil & Environmental Engrg., Univ. of Ulsan) ;
  • Hong, Seung-Seo (Dept. of Geotechnical Engrg. Research, Korea Institute of Civil Engrg. and Building Technology)
  • 신호성 (울산대학교 건설환경공학부) ;
  • 홍승서 (한국건설기술연구원 지반연구본부)
  • Received : 2022.02.21
  • Accepted : 2022.02.27
  • Published : 2022.03.31
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Abstract

Domestic district heating system needs safety management guidelines using the change of surface temperature to detect damages to buried heat pipes. This paper performed numerical analyses on the temperature change of ground surface due to the burial and leakage of heat pipes. Temperature difference between the ground surface above the buried heat pipes and the surrounding surface rises to a crescendo between 3 am and 8 am. It is more significant in winter rather than in summer. Low groundwater level magnifies the temperature increase of the ground surface by the heat pipe, which is smaller in the asphalt pavement than in the bare soil. Without leakage of the buried heat pipe, the temperature increment on the ground surface by the heat pipe is within 3.0℃ in the bare soil and 3.5℃ in the asphalt pavement. Leakage of the supply heat pipe in the bare soil increases the temperature on the ground surface gradually in the summer but rapidly in the winter. Asphalt pavement shows a lower increment and increasing rate of the temperature on the ground surface due to pipe leakage than bare soil surface. And leakage on both sides of the supply pipe takes 1-2 days for the temperature difference from the surrounding soil surface to reach 10℃.

국내의 지역난방을 위해 지중에 매설된 열수송관은 노후화로 인한 손상을 감지하기 위하여 지표면 온도변화에 기반한 안전관리 기준이 필요하다. 본 논문은 열수송관의 매설과 누수로 인한 지표면 온도 변화에 대하여 수치해석을 수행하였다. 열수송관이 매설된 지면과 주변지면의 온도차는 오전3시~오전8시에 가장 크게 나타났으며, 하절기 보다는 동절기에 온도차가 크게 발생하였다. 지하수위의 하강은 열수송관에 의한 지표면의 온도 증가를 크게 하고, 아스팔트 지면조건은 토사 지면조건에 비하여 지하수위 변화의 영향이 작게 나타났다. 열수송관의 누수가 없는 경우, 열수송관에 의한 지표면 온도 상승은 토사지반에서 3.0℃, 아스팔트 포장에서는 3.5℃이내로 나타났다. 토사 지면조건에서 열수송관의 누수에 의한 지면온도 변화는 하절기에는 완만하게, 동절기에는 급격하게 상승하였다. 아스팔트 포장조건은 토사 지면조건보다 누수에 의한 지표면의 온도 상승폭과 상승률이 작게 나타났다. 그리고 공급관의 양측 누수에 의하여 수송관 상부 지면과 주변지면의 온도차이가 10℃에 도달하는데 1~2일 정도 소요되었다.

Keywords

Acknowledgement

본 연구는 한국연구재단 개인연구지원사업(NRF-2019R1A2C200441913)과 한국건설기술연구원의 "지하매설 압력관의 실시간 건전성 진단 및 관리 기술 개발" 연구의 지원으로 수행되었으며, 이에 깊은 감사를 드립니다.

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