Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering Conference
Shanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Experimental and numerical investigations on liquid sloshing under the external excitation
Zhen Zhang, Gaoli Wang, Qiaorui Wu, Yonghe Xie and Huimin Yu
College of Naval Architecture and Maritime, Zhejiang Ocean University.
Zhoushan, Zhejiang, China

movement of the liquid tank through experiments observed thephenomenon of liquid hitting the bulkhead caused by sloshing andcollected the slamming pressure. At last, they also analyzed therelationship between the slamming pressure and the shape of the wave
surface. Delorme (2009) applied roll excitation to the rectangular tankand then analyzed the slamming pressure caused by liquid tank sloshing.
It is finally found that the frequency when the maximum value ofslamming 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 sloshingpressure. Later, numerical methods have been adopted widely inadvance of its low cost and convenience. Milkeliset al. (1984) and Araiet 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 fluidstructure interaction problem. Lee et al. (2007) studied the fluid-solid
coupling problem of structural large-deformation in elastic tanks. Dsaet al. (2020) estimated the capability of using U-shaped containers asdampers 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 amulti-layered VOF method to simulate two-layered liquid sloshing in arectangular tank subjected to horizontal excitations. Jung et al. (2020)
examined the effects of the vertical baffle heights on the liquid sloshingin 3D tanks.
Many authors have investigated liquid sloshing by numerical methods.
Although numerical methods are suitable to investigate the liquidsloshing, its accuracy should be verified by experiments. As such, thispaper designed experiment to study the effect of the external excitation
on liquid sloshing. The liquid tank filled in 25% liquid is forced byrolling and the changes of free surface are captured by camera. Thenthe strain caused by the impact of liquid sloshing on the wall iscaptured by strain gauges. The pressure acting on the bulkhead isobtained by the relationship of the stress-strain. At last, 3D model isadopted to simulate in numerical method. The results achieved bynumerical method are compared to that of the experiments. It is foundthat liquid sloshing in the tank which rolls is violent when thefrequency of the excitation is close to the natural frequency.

ABSTRACT
Liquid sloshing inside a partially filled tank has a great impact on thefragile internal tank coating and also on the stability of oil-carrier ships.
A series of experiments have been carried out in a hydraulic shaker toestimate the pressure developed on the tank walls with the liquid tankrolling. 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 sloshingon the wall with the excitation changing. It has been found that theliquid tank rolls violently when the frequency of the external excitation
is close to the natural frequency of the liquid sloshing.

KEY WORDS: liquid tank sloshing; natural frequency; experimental
study; VOFINTRODUCTION
The cargoes carrying liquid including VLCC, LNG, LPG will have asloshing effect in the tanks during navigating. Liquid sloshing inside apartially filled tank has a great impact on the fragile internal tankcoating and also on the stability of carrier ships. Physically, sloshingrefers to the flow of fluid in a limited space following the movement ofa limited space. Due to the arbitrariness of fluid flow and therandomness of motion in limited space, the flow of free liquid surface
often exhibits greater randomness and nonlinearity, so it is of greatscientific 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 liquidsloshing in recent years. Abramson (1996) who researches liquidsloshing early adopted potential flow theory to investigate sloshing inspherical and cylindrical tanks. Faltisen (2000) developed a discrete
multi-modal system based on the nonlinear potential flow theory andthe Bateman-Luke variational principle, by which the system exploredthe 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 the2451