Abstract
Conventional liquefied natural gas (LNG) vessels with membrane cargo containment systems have tank filling restrictions from 0.10 to 0.70 H (with H the internal tank height). The main reason for such restrictions is high sloshing loads around these filling depths. The new designs of prismatic LNG cargo tanks are proposed by increasing the lower chamfer length. Numerical sloshing analysis was used to optimize tank shape out of the several candidates. To validate the effectiveness of the modified tank, 1/50 scaled model tests were conducted. In these tests, 24 different irregular seaways were tested for both the conventional and the optimized tank and their statistical pressures were compared. Modified tank design was quite effective in reducing sloshing loads for a 0.30 H filling depth, and it did not significantly increase sloshing loads at other filling conditions. This study demonstrated the possibility of all filling operations for an LNG cargo containment system.
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References
American Bureau of Shipping (2009) Guidance Notes on Strength Assessment of Membrane-Type LNG Containment Systems under Sloshing Loads. Guidance note, Houston, USA
Lloyd’s Register (2009) Sloshing Assessment Guidance Document for Membrane Tank LNG Operations. Guidance note, London, UK
Lee H, Kim JW, Hwang C (2004) Study on coupling effects of ship motion and sloshing. J Ocean Eng 34:2176–2187
Macdonald AJ (2008) Lloyd’s Resister’s guidance on the operation of membrane LNG ships to avoid the risk of sloshing damage. In: Proceedings of GASTECH, Bangkok, Thailand
Pastoor W, Tveitnes T, Valsgard S, Sele HO (2004) Sloshing in partially filled LNG tanks: an experimental survey. In: Proceedings of the 5th offshore technology conference, OTC, Houston, USA
Zhao R, Rognebakke O, Zheng X (2004) Wave and Impact Loads in Design of Large and Conventional LNG Ships. In: Proceedings of RINA conference of design and operation of gas carriers, London, UK
Anai Y, Ando T, Watanabe N, Murakami C, Tanaka Y (2010) Development of a New Reduction Device of Sloshing Load in Tank. In: Proceedings of the 20th international offshore and polar engineering conference, ISOPE, Beijing, China
Kim Y, Kim SY, Ahn Y, Kim KH, Jeon SE, Shu YS, Park JJ, Hwangbo SM (2013) Model-scale sloshing tests for and anti-sloshing blanket system. Int J Offshore Polar Eng 23(4):252–254
Ha MK, Kim MS, Paik BK, Park CH (2002) Motion and sloshing analysis for new concept of offshore storage unit. Int J Ocean Eng Tech 16(1):1–7
Park JJ, Kim MS, Kim YB, Ha MK (2006) Practical Application of Numerical Sloshing Analysis for Development of Large LNG Carriers. In: Proceedings of the 16th international offshore and polar engineering conference, ISOPE San Francisco, USA
Lloyd’s Register (2012) Guidance on the Operation of Membrane LNG Ships to Reduce the Risk of Damage due to Sloshing, Guidance note, London, UK
Nichols BD, Hirt CW (1971) Improved free surface boundary conditions for numerical incompressible-flow calculations. J Comp Phys 8:434–448
Lloyd ARJM (1989) Seakeeping : Ship behavior in rough weather. Ellis Horwood Ltd, UK
Maillard S, Brosset L (2009) Influence of Density Ratio between Liquid and Gas on Sloshing Model Test Results In: Proceedings of the 19th international offshore and polar engineering conference, ISOPE, Osaka, Japan
Ahn Y, Kim SY, Kim KH, Lee SW, Kim Y, Park JJ (2012) Study on the Effect of density Ratio of Liquid and Gas in Sloshing Experiment. In: Proceedings of the 22nd international offshore and polar engineering conference, ISOPE, Rhodes, Greece
Kim, SY, Kim Y, Kim, KH (2013) Statistical Analysis of Sloshing-Induced Random Impact Pressures. J Eng Mari Env [Online] Available: http://pim.sagepub.com
Chun SE, Hwang JO, Chun MS, Lee JM, Suh YS, Hwangbo, SM (2011) Direct Assessment of Structural Capacity against Sloshing Loads using Nonlinear Dynamic FE analysis including Hull Structural Interactions. In: Proceedings of the 21st international offshore and polar engineering conference, ISOPE, Hawaii, USA
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Park, JJ., Kim, SY., Kim, Y. et al. Study on tank shape for sloshing assessment of LNG vessels under unrestricted filling operation. J Mar Sci Technol 20, 640–651 (2015). https://doi.org/10.1007/s00773-015-0318-1
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DOI: https://doi.org/10.1007/s00773-015-0318-1