• Dr. Sang-Eon Chun
  • Samsung Heavy Industries, Ltd.
  • 118C Surge Building
  • 4:00 p.m.
  • Faculty Host: Dr. Rakesh Kapania

 

Sloshing remains an issue for LNG (Liquefied Natural Gas) industry, particularly for LNG tankers and FPSO/FSRU, etc., with membrane-type LNG CCS (Cargo Containment System), which use the hull structure as the load bearing tank body and have the relatively soft insulation material between the LNG cargo and the hull structure. The insulation material structure is adopted only to maintain the low temperature inside the tank and to protect the hull structure from being exposed to the critically low temperature. If the baffle plates are introduced to reduce the sloshing motion inside the LNG tanks, it is unavoidable to support them onto the load bearing hull structure, which inevitably leads to heat paths and deteriorates the insulation performance of the LNG CCS. Therefore, the sloshing issues in the membrane-type LNG CCS are partially treated by adopting the octagonal shape to reduce the impact load due to sloshing motion and reinforcing the insulating structures of LNG CCS, which is supposed to be constrained by economic and technical limitations. In spite of these design changes, the sloshing concern relating to possible damages on the CCS is still limiting the operating conditions and so the new business chances; LNG tankers are allowed to operate with the LNG cargo filled more than 80% or less than 10% of the tank height.

In this paper, a unique and innovative solution to the sloshing conundrum, named as ABAS (Anti Boil-off gas Anti Slosh) blanket system, is unveiled, which can dampen the motion of LNG inside the LNG cargo vessels in operation in a cheap and effective way and, as a result, the sloshing loads on CCS can be reduced significantly. This design concept has been proved through various sloshing model tests, which show the dramatic reduction of sloshing motion. Finally, the production of prototypes of floating unit structures which are assembled into a floating blanket layer, ABAS blanket system, shows the applicability in real LNG vessels.

And in conclusion, the speaker will share his own experiences to solve the technical issues based on the Seven Da Vincian principles in the book of How to Think like Leonardo Da Vinci written by Michael Gelb.