Effects Of Sloshing Loads On Fatigue Strength Of Independent Type B Lng Tank

The objective of the present study is to investigate the load effects due to sloshing impact on the fatigue assessment of an independent type B LNG tank. The selection of the cargo containment system type for an FLNG (Floating LNG) is mainly related to the sloshing problem. FLNG are considered to be operating at an intermediate loading condition prone to sloshing inside the containment system. One of the most popular LNG containment systems for the FLNG is an independent prismatic tank categorized as IMO (International Maritime Organization) type B tank, in which the ship hull supports the LNG tanks. It is recognized that the independent type B tank is free from possible liquid sloshing inside the tank from the standpoint of its strength due to its stiffened panel structure. However, from the standpoint of fatigue assessment of the cargo tank, it needs careful verification. In the present study, the sloshing impact pressures on the internal structures of an independent type B tank are predicted based on scaled sloshing model tests using a 2D rectangular tank with internal structures. Finally, a fatigue assessment based on the sloshing model results is carried out to quantify the effects of sloshing loads on the fatigue strength of an independent type B tank.