Most studies in the field of rollover in stratified Liquefied Natural Gas(LNG) have only focused on onshore storage tanks. The objective of thisstudy was to investigate the effect of the forced convection caused by thecargo tank motions from sea waves on the heat and mass transferbetween LNG layers. The effect of rolling motion on the pattern ofrollover was researched by means of simulation. By comparing the LNGrollover process under static conditions, the results show that the mixingbetween the upper and lower layers is mainly influenced by the dynamicliquid motion. Liquid motion enhances the heat and mass transfer ratebetween layers in the cargo tank, and the evolution time of the rolloveris greatly reduced. Moreover, shortening of the rolling period enhancesthe dynamic effect of liquid motion, accelerates the mixing of layers. Todeeply understand the hazard of rollover under offshore conditions,applying a rolling excitation (at ğœƒ= 6°and ğ‘“= 0.08 Hz) to two staticcargo tanks that have stored a large amount of energy by heat ingress.The results show the peak of boil-off rate caused by rolling mainlydepends on the amount of energy that the stratification has already stored.These results can provide a corresponding basis for preventing rolloverin the LNG cargo tank under rolling motion.
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