Recently Eco-friendly Energy has been getting interesting more and more with the exhaustion of fossil fuel and the environmental regulation has being increased over the world. Liquefied natural gas (LNG) is a hot issue in such a global trend. Already a little amount of LNG is used as substitute of fossil fuel U.S.A and Other countries in the Europe and the amount is expected to be increased lastingly. And besides, the research and development of the ships is very active which store and carry LNG or use LNG as fuel. Cargo tanks and fuel oil tanks related to them are very active. NO 96 type and Mark III type has structurally the problems on Filling Limit caused by Sloshing and Safety of Cargo tank on impact, and First of all, Safety for Collision, being stranded and Sloshing should be approved for Arctic LNGC, LNG Floater and LNG fuelled vessels. We introduce the IMO type "B" independent LNG tank and evaluate structural stability of the independent tank considering the structure that supports cargo.
Cargo tanks (Membrane type) of existing LNG ship have damage problems by flow and external impact of cryogenic liquefied gas during shipping. Independent LNG cargo tank (IMO Type "B") has the advantage of structural safety for sloshing, internal flow and external impact. This independent LNG cargo has problem for strength of cargo tank support structure between cargo tank and hull structure. In this study, 3D cargo hold analysis for the LNG carrier applied the independent LNG cargo tank of STX (including support structure) was carried out. Material of hull structure is mild or higher tensile steel plate and material of LNG cargo tank is aluminum (Al 5083-O). Support structures are consisted of vertical support, anti-rolling support, anti-pitching support and anti-floating support.