Liquid sloshing inside a partially filled tank has a great impact on the fragile internal tank coating and also on the stability of oil-carrier ships. A series of experiments have been carried out in a hydraulic shaker to estimate the pressure developed on the tank walls with the liquid tank rolling. Pressure studies are done on the basis of changing excitation frequency of the shaker. In addition, numerical method was constructed and validated against experimental results showing good agreement. The main focus is to measure the impact caused by liquid tank sloshing on the wall with the excitation changing. It has been found that the liquid tank rolls violently when the frequency of the external excitation is close to the natural frequency of the liquid sloshing.
The cargoes carrying liquid including VLCC, LNG, LPG will have a sloshing effect in the tanks during navigating. Liquid sloshing inside a partially filled tank has a great impact on the fragile internal tank coating and also on the stability of carrier ships. Physically, sloshing refers to the flow of fluid in a limited space following the movement of a limited space. Due to the arbitrariness of fluid flow and the randomness of motion in limited space, the flow of free liquid surface often exhibits greater randomness and nonlinearity, so it is of great scientific significance to study it to reveal complex motion laws. In addition, methods for studying sloshing problems: experimental research, mathematical analysis and numerical simulation.
There are many researchers investigating on the issue about liquid sloshing in recent years. Abramson (1996) who researches liquid sloshing early adopted potential flow theory to investigate sloshing in spherical and cylindrical tanks. Faltisen (2000) developed a discrete multi-modal system based on the nonlinear potential flow theory and the Bateman-Luke variational principle, by which the system explored the nonlinear sloshing problem in a three-dimensional tank. Many authors present experimental researches to record the change of liquid free surface. Such as Bagnold et al. (1939) who simulated the movement of the liquid tank through experiments observed the phenomenon of liquid hitting the bulkhead caused by sloshing and collected the slamming pressure. At last, they also analyzed the relationship between the slamming pressure and the shape of the wave surface. Delorme (2009) applied roll excitation to the rectangular tank and then analyzed the slamming pressure caused by liquid tank sloshing. It is finally found that the frequency when the maximum value of slamming pressure appeared was lower than the first-order natural frequency of tank sloshing. Xue (2017) and Yu (2020) conducted experiments to investigate effective suppression methods for sloshing pressure. Later, numerical methods have been adopted widely in advance of its low cost and convenience. Milkeliset al. (1984) and Arai et al. (1984) simulated the two-dimensional sloshing problem based on the MAC method of finite difference. Oger (2009) described a numerical algorithm based on the SPH method to solve the fluid-structure interaction problem. Lee et al. (2007) studied the fluid-solid coupling problem of structural large-deformation in elastic tanks. Dsa et al. (2020) estimated the capability of using U-shaped containers as dampers via some experiments. And then they applied 2D and 3D numerical models to simulated sloshing with the results being in good agreement with those of the experiments. Liu et al. (2021) developed a multi-layered VOF method to simulate two-layered liquid sloshing in a rectangular tank subjected to horizontal excitations. Jung et al. (2020) examined the effects of the vertical baffle heights on the liquid sloshing in 3D tanks.