Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Study on Local Buckling of District Heating Pipes Using Limit State Design

한계상태 설계법을 이용한 지역난방 열배관의 국부좌굴 연구

  • Kim, Joo-Yong (Dept. of Mechanical Engineering, Inha Univ.) ;
  • Lee, Sang-Youn (Dept. of Mechanical Engineering, Inha Univ.) ;
  • Ko, Hyun-Il (District Heating Technology Research Institute, Korea District Heating Corp.) ;
  • Cho, Chong-Du (Dept. of Mechanical Engineering, Inha Univ.)
  • Received : 2010.05.10
  • Accepted : 2010.10.12
  • Published : 2010.12.01
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Abstract

The district heating system distributes the heat generated from a cogeneration plant to wider locations. In this process, the district heating pipe (DHP) is subjected to internal and external loadings. The internal loadings are generally caused by the operating conditions such as water temperature and internal pressure. Frictional interactions between the pipes and the soil contribute to the external loadings. Thus, investigation of the mechanisms of failure of DHPs will help to guarantee both mechanical stability and heating efficiency. In this study, we investigate the local buckling of DHPs using limit state design (LSD). Two methods are considered: the use of the limit state for the width-thickness ratio and the use of the limit state for the strain. The results are used to confirm that the DHP is stable under local buckling. Finally, we suggest a minimum preheating temperature for avoiding local buckling.

지역난방은 열병합 발전소에서 생산된 열을 온수의 형태로 열배관 네트워크를 통해 넓은 지역에 일괄적으로 공급하는 난방시스템이다. 일반적으로 지역난방 열배관은 지중에 매설되며 내부를 흐르는 온수의 압력과 온도변화, 매설 토사와의 마찰 및 반력에 의한 하중을 받게 되므로 열공급 효율과 함께 기계적인 안전성에 대한 검토가 반드시 필요하다. 본 논문에서는 강관의 한계상태 설계법을 이용하여 한계판폭두께비와 한계변형률, 두 가지 관점에서 열배관의 국부좌굴 발생여부를 평가하였으며 그 결과 현재 국내에서 사용되고 있는 모든 열배관은 국부좌굴이 발생하지 않음을 확인하였다. 마지막으로 국부좌굴을 피하기 위한 최소 예열온도를 산출함으로써 예열온도에 대한 시공 기준을 제시하였다.

Keywords

References

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