Turbulence analysis for vertical baffle configurations on prismatic tanks by the MPS method

Abstract

A series of conceptual baffles have been proposed to attenuate pressure effects provoked by sloshing on the walls of Liquefied Natural Gas (LNG) tanks. However, these structures provoke turbulent behavior that need to be analyzed to avoid non-desired fluid effects. In this work, numerical sloshing analyses are developed by a two dimensional Moving Particle Semi-implicit (MPS) method applying the Sub-Particle-Scale Large Eddy Simulation (SPS-LES) turbulent model to identify the turbulent effects due to global motions on a prismatic LNG tank for two filling fractions. The impact pressure, total force, and total moment on tank walls are compared to a prismatic tank without baffles, one configuration with one baffle and two configurations with two baffles. The results illustrate the turbulence effects generated by the three baffle configurations on partially filled tanks (25% and 50% of filling fraction) showing that the effect of the baffles to reduce sloshing effects is more significant for low filling levels (25% of filling fraction), and also, there is a small difference on the sloshing reduced effects between one baffle or two baffles at different separations. However, important turbulent effects appear for high filling levels (50% of filling fraction) specially at roll motion.