Journal of the Computational Structural Engineering Institute of Korea (한국전산구조공학회논문집)

Computational Structural Engineering Institute of Korea (한국전산구조공학회)
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Study on Structural Strength of Mark III type LNG Cargo Containment System by Idealized Triangular Impulse Load

MarkIII LNG 방열 시스템의 강도평가를 위한 삼각형 충격 하중에 대한 구조응답에 대한 연구

  • Hwang, Se Yun (Department of Naval Architecture and Ocean Engineering, Inha Univ.) ;
  • Kim, Sung Chan (Department of Naval Architecture and Ocean Engineering, Inha Tech. Col.) ;
  • Lee, Jang Hyun (Department of Naval Architecture and Ocean Engineering, Inha Univ.) ;
  • Nho, In Sik (Department of Naval Architecture and Ocean Engineering, Chungnam Univ.)
  • 황세윤 (인하대학교 조선해양공학과) ;
  • 김성찬 (인하공업전문대학 조선해양과) ;
  • 이장현 (인하대학교 조선해양공학과) ;
  • 노인식 (충남대학교 선박해양공학과)
  • Received : 2014.10.30
  • Accepted : 2014.11.21
  • Published : 2014.12.31
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Abstract

It has been well known the sloshing pressure has complex shape and various patterns. The pattern of sloshing pressure is variously characterized by the pressure amplitude, duration time and skewness. The structural response induced by the sloshing pressure is also affected by the pattern of sloshing pressure and the type of structural members. In order to understand the structural response by the perspective view of categorized pattern, it is more efficient to make simple sloshing pressure pattern than to reflect the complex pressure history. In this study, the sloshing pressures obtained by the small scale model test are simplified with respect to their duration and skewness. Dynamic analyses of Mark-III LNG CCS are then parametrically performed with the consideration of various types of sloshing impact. Meanwhile, the failure pressures given the duration and skewness are investigated after parametric calculations are conducted to investigate the effect of pressure parameters on the structural response.

LNG 방열 시스템의 선형 동적해석 모델을 사용하여 슬로싱 충격 압력을 구조해석에 적용 시 사용되는 이상화된 삼각파 압력에 대해서 검토하였다. 삼각파 압력의 최대값, 지속시간, 비대칭성의 충격파에 대한 구조 안전성 평가를 위해서 멤브레인 구조의 허용기준과 슬로싱 압력에 관련된 간략화된 파괴압력에 대해 검토하고, 슬로싱 충격 압력의 지속시간과 비대칭성으로 특징 지워진 이상화된 삼각파 형상의 압력을 고려한 일련의 선형 동적해석을 수행하여 설계기준으로 사용할 파괴압력을 도출하였다. 본 논문에서 제시한 방법을 통해서 방열시스템 구조 요소의 안전성을 평가하기 위한 파괴 압력을 선정할 수 있고 모형실험을 통한 슬로싱 압력과의 비교를 통하여 방열시스템의 구조안전성을 평가할 수 있을 것이라 판단된다. 또한 해석결과를 통해 방열시스템에서의 최대 응력은 매우 짧은 순간의 충격하중 하에서는 압력의 비대칭성 보다는 하중 지속시간에 많은 영향을 받고 있음을 검토하였다.

Keywords

References

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