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Development of Equations for Dynamic Design Loads of Sphere Type LNG Tank with Cylindrical Extension

원통 확장부를 갖는 구형 LNG 탱크의 동적 설계하중 산출식 개발

  • Shin, Sang-Hoon (Department of Aero Mechanical Engineering, Kyungwoon University) ;
  • Ko, Dae-Eun (Department of Naval Architecture and Ocean Engineering, Dong-Eui University)
  • 신상훈 (경운대학교 항공기계공학과) ;
  • 고대은 (동의대학교 조선해양공학과)
  • Received : 2017.01.24
  • Accepted : 2017.05.12
  • Published : 2017.05.31

Abstract

The number of shops needed for the fabrication of a sphere type cargo tank for an LNG carrier is proportional to the size of the tank to be constructed. Due to the limitations of facility investment, it is difficult to fabricate various size tanks with a perfectly spherical shape in the (factory). An efficient method of increasing the capacity of the cargo tank is to extend the conventional sphere type LNG tank vertically by inserting a cylindrical shell structure. In this study, equations for the dynamic pressure distribution due to horizontal acceleration are derived for a sphere type LNG tank with central extension. The derived equations can be easily applied to the design and structural assessment of a sphere type LNG tank with central extension. Furthermore, the results of this study can be combined with the static design loads previously reported by Shin & Ko [9], in order to establish a simplified analysis method which enables a precise initial estimate to be obtained, thereby obviating the need for a time consuming finite element analysis.

Keywords

Cylindrical extension;Dynamic pressure distribution;Initial estimate;Simplified analysis method;Sphere type LNG tank

References

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