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Development of Numerical Analysis Model for the Calculation of Thermal Conductivity of Thermo-syphon

열 사이펀의 열전도율 산정을 위한 수치해석 모델 개발

  • Park, Dong-Su (Dept. of Convergence Study on the Ocean Science and Technology, Korea Maritime and Ocean Univ.) ;
  • Shin, Mun-Beom (Dept. of Convergence Study on the Ocean Science and Technology, Korea Maritime and Ocean Univ.) ;
  • Seo, Young-Kyo (Dept. of Ocean Engrg., Korea Maritime and Ocean Univ.)
  • 박동수 (한국해양대학교 해양과학기술융합학과) ;
  • 신문범 (한국해양대학교 해양과학기술융합학과) ;
  • 서영교 (한국해양대학교 해양공학과)
  • Received : 2020.09.01
  • Accepted : 2020.11.24
  • Published : 2021.01.31

Abstract

The areas consisting of frost susceptible soils in cold regions, such as the Arctic area, have problems of frost heave and thaw settlement due to the seasonal air temperature changes and internal temperature of installed structures. Ground stabilization methods for preventing frost heave and thaw settlement of frost susceptible soils include trenching, backfilling and thermo-syphon. The thermo-syphon is the method in which refrigerant can control the ground temperature by transferring the ground temperature to atmosphere in the from of two-phase flow through the heat circulation of the internal refrigerant. This numerical study applied the function of these thermo-syphon as the boundary condition through user-subroutine coding inside ABAQUS and compared and analyzed the temperature results of laboratory experiments.

북극권과 같은 한대지역의 동상민감성 지반은 계절적 대기 온도 변화 및 설치된 구조물의 온도에 의해 지반의 융기 및 침하 문제가 존재한다. 이러한 동상민감성 지반의 융기 및 침하 방지를 위한 지반안정화 공법으로는 매립 및 치환공법, 열 사이펀 등이 존재한다. 여기서 열 사이펀이란 내부 냉매의 증발, 응축을 반복하며 열 순환을 통해 이상 유동(two-phase flow)의 형태로 냉매가 지반의 온도를 외부로 전달하여 지반 온도를 조절 할 수 있는 공법이다. 본 연구는 이러한 열 사이펀의 성능을 열전도율로 수치화하기 위하여 ABAQUS 내부의 User-subroutine 코딩을 통해 열 사이펀을 지중의 한 열원으로 간주, 경계조건으로 적용시켜 기존 문헌의 열 사이펀 실내모형실험의 온도분포 결과와 비교하여 산정하였다.

Keywords

References

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