Journal of the Society of Naval Architects of Korea (대한조선학회논문집)

The Society of Naval Architects of Korea (대한조선학회)
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A Study on the Buckling Strength of the Skirt Structure in the Spherical LNG Carriers

구형 LNG운반선의 탱크지지 구조인 스커트의 좌굴강도에 대한 연구

  • Kim, Ul-Nyeon (Hyundai Maritime Research Institute, Hyundai Heavy Industries Co., Ltd.)
  • 김을년 (현대중공업 선박연구소)
  • Received : 2017.01.25
  • Accepted : 2017.09.06
  • Published : 2017.10.20
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Abstract

This paper deals with the buckling strength of the skirt structure in the spherical LNG carriers. The spherical cargo tank systems consist of spherical tank, skirt, tank cover, pump tower, etc. The skirt supports the spherical cargo tank and is connected with ship hull structure. It is designed to act as a thermal brake between the tank and the hull structure by reducing the thermal conduction from the tank to the supporting structure. It is built up of three parts, upper aluminum part, middle stainless steel part and lower carbon steel part. The 150K spherical LNG carrier was designed and carried out the strength verification under Classification Societies Rule. The design loads due to acceleration, thermal distribution, self-weight and cargo weight were estimated considering requirements of the Class Rule and numerical simulation analyses. Based on the obtained design loads and experienced project data, the initial structure scantling was carried out. To verify the structural integrity, theoretical and numerical analyses were carried out and strength was evaluated aspect of buckling capacity. The results by LR and DNV design code are shown and discussed.

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References

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