Minimising the sloshing impact in membrane LNG tank using a baffle

Wang, Wei and Xiong, Ye Ping (2014) Minimising the sloshing impact in membrane LNG tank using a baffle. In Proceedings of the 9th International Conference on Structural Dynamics (EURODYN 2014). European Association for Structural Dynamics. pp. 3171-3177 .

Abstract

Liquidised Natural Gas (LNG) is transported by LNG ships and it will slosh in partially filled tanks. This will
cause damage to tank structures, e.g. cracks and fatigue, and affect ship’s stability. This paper presents numerical studies of LNG sloshing in partially filed membrane tank with a baffle on the bottom using Finite Volume Method to minimise impact pressure. The software Gambit and Fluent are used to generate the mesh and simulate the LNG sloshing motion. The LNG sloshing behaviour is analysed considering a two-dimensional membrane tank which moved in one direction only for each case studies. Two cases of the tank motions are considered, i.e., sway and roll. The LNG tank is excited by a regular sinusoidal wave and the excitation frequency is set as the natural frequency. Liquid filling levels considered are 25%, 50% and 75% of the tank depth,respectively. Moreover, the numerical results of the impact pressure are compared with the published experimental results and show good agreement. Furthermore, a vertical baffle is inserted on the bottom of the tank to control the maximum impact pressure and results are compared with non-baffle cases. The key findings are: the effect of liquid depth on the maximum impact pressure for rotational motion is more significant comparing with the horizontal motion and offer solutions for reducing impact pressure effectively. The maximum impact pressure for the tank with baffle is reduced nearly 50% comparing with the cases without baffle on the bottom of the tank.

This record has no associated files available for download.

Contributors

Author: Ye Ping Xiong

Download statistics