This paper describes the evolution of stratified liquid natural gas(LNG) from its formation to its breakdown (rollover). We simulated the density field and heat transfer process of stratified LNG in a storage tank in salt water modeling experiments, according to the similarity law. The goal of this paper is to develop and validate tools that can be used to make predictions about the conditions under which stratification and rollover could happen. In our modeling experiments, we studied the formation of swatification, the evolution from stratification to rollover, and found that evolution consisted of two principle phases: a quiescent phase in which the interface between the two layers was basically stationary; and an unstable phase characterized by a migrating interface that culminated in rollover. Our data showed that= (1) When density differences were greater than 0.63kg/m3, stratification occurred; and (2) As the density difference increased, the interface height increased. A higher interface height meant that a more serious rollover occurred. Furthermore, greater injection speed can increase the interface height. (3)In our study the occurrence of rollover was related.to the density difference of stratified LNG, the lower liquid height, and heat flux leakage through the shell of the tank during storage. A greater heat flux, smaller density difference, and smaller interface height could advance the time to rollover.
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