## 2 Literature Review
Advancements in the computational performance of numerical algorithms have led to numerical methods, such as the boundary element method (BEM), the finite element method (FEM), and the finite volume method (FVM), becoming popular in this field. For example, [PERSON] and [PERSON] [9] developed a BEM-based theoretical model of damping for horizontal and vertical baffles. They validated the theoretical model and investigated the effectiveness of various baffle configurations by experimentally measuring hydrodynamic damping in terms of total energy and the average rate of energy dissipation. This revealed that the characteristics of hydrodynamic damping were affected by the baffle configuration, such as relative depth, baffle elevation, baffle length, and fluid surface elevation. Specifically, they found that relative baffle length and its variation with relative depth could be adjusted to maximise the baffle damping coefficient, and that baffles close to the free surface were more damping than those at other locations. In addition, they noted that horizontal baffles were most effective for tall tanks, whereas vertical baffles were most effective for shallow tanks. [PERSON] and [PERSON] [10] developed a variational BEM and used it to investigate the effect of a rigid baffle on the natural frequencies of the liquid in a cylindrical rigid container. They validated the applicability of the variational BEM to liquid sloshing problems and found that a baffle could decrease the natural frequencies of liquids. [PERSON] et al. [11] developed a mode superposition method based on modal analysis and applied this method to the sloshing response of a liquid in a rigid cylindrical container with multiple rigid annular baffles under both harmonic- and seismic-lateral excitation. This revealed that optimisation of the inner radius ratio and position minimised the resultant hydrodynamic force and moment under harmonic excitation. [PERSON] et al. [12] proposed an equivalent mass-spring mechanical model to replace continuous fluid analysis in a rigid cylindrical tank with a rigid annular baffle under horizontal excitation. They found that a baffle in a high position and/or with a small inner radius effectively reduced the convective shear force but increased the impulsive shear force. In addition, they identified that as a baffle's inner radius increased, the convective overturning moment monotonically decreased but the impulsive overturning moment increased. Studies have also developed FVM-based flow analysis methods. [PERSON] and [PERSON] [13] developed two 3D FVM modelling methods based on the large eddy simulation approach and the volume of fluid (VOF) method for a tank with baffles, and conducted a validation study for a two-dimensional (2D) liquid sloshing in a tank with and without baffles. They found that a vertical baffle was more effective than a horizontal baffle in reducing the sloshing amplitude. [PERSON] et al. [14] used 3D FVM modelling methods with the VOF scheme to investigate the effect of vertical baffle height on sloshing in a laterally moving 3D rectangular tank. They identified that as the baffle height increased, sloshing was more suppressed, due to augmentation of the blockage effect of the baffle. This resulted in additional viscosity and energy dissipation, i.e., hydrodynamic damping. [PERSON] et al. [15] developed numerical modelling methods based on the FVM approach with the VOF method and experimentally investigated the effect of floating plates on sloshing in a membrane-type liquefied natural gas at three different filling ratios under purely harmonic roll excitation. They found that when the excitation frequency approached the lowest natural frequency, the U-tube mode, which played a significant role in decreasing sloshing, was operative in a tank with two floating plates. They concluded that the floating plates not only reduced wave run-up along the longitudinal bulkhead but also decreased impact loads on the bulkhead at low excitation amplitudes at a 70% filling ratio. [PERSON] et al.