Numerical Simulation of Rollover Phenomena for FLNG Application

LNG is a clean source of energy; when burnt it has lower associated NOx and SOx emissions than other fossil fuels. Because of environmental issues and price, FLNG projects are developed in many areas. LNG with different density and temperature could stratify in a storage tank. Rollover is one of the major issues concerning the safety and mechanical stability of storage and transportation facilities for LNG. Rollover refers to the rapid mixing of stratified LNG layers due to the equalization of their mass densities over time caused by heat and mass transfer between the layers. For estimation of rollover phenomena by numerical analysis, REFPROP and MATLAB are used as a new simulation link; REFPROP is used to calculate the physical properties of LNG as a function of temperature, pressure and composition, and MATLAB is used to solve the coupled ordinary differential equations describing the material and energy balance relations. We assumed the scenario of rollover cases in FLNG tanks, and the results are described.