## 6 Conclusions  
The purpose of this paper was to study the green-water loads and structural responses of ship bow structures induced by freak waves. To achieve this, a three-dimensional  
Figure 22: Comparison of nonlinear dynamic analysis and linear dynamic analysis methods: (**a**) The Mises stress at the deck D111, (**b**) the displacement at the deck D111, (**c**) the Mises stress at B101 of the stiffener, and (**d**) the displacement at B101 of the stiffener. numerical wave tank was established to generate freak waves and to obtain the wave-ship interaction and green-water loads. A finite element model of the ship bow was built, on which the green-water loads were applied to obtain the displacement and stress of the deck and breakwater structures. The main conclusions are as follows:  
1. It can be concluded from numerical simulation results that freak waves have a crucial impact on ship motion response. It should be noted that wave crests and troughs can cause significant heave and pitch motion. Therefore, it is necessary to consider the influence of extreme sea conditions on ship stability in the design and verification of ships. 2. Freak waves have significant impacts on green-water loads. The green-water event caused by freak waves generates a huge impact force on the deck and breakwater of the ship bow, with a greater slamming load on the breakwater than on the deck. The tremendous impact loads may pose a threat to the safety of personnel on the deck and cause damage to the equipment on deck. Therefore, in engineering applications, it is necessary to pay attention to checking the local strength of the bow deck and the breakwater to ensure the safety of the ship and personnel. 3. Freak waves are able to cause severe structural responses in the deck and breakwater structures of the ship bow. Under the impact of green water caused by the freak wave, the breakwater and breakwater stiffener suffered relatively severe damage. Therefore, in the design of ships, it is necessary to strengthen the structure of the breakwater to prevent damage to the breakwater caused by green-water events resulting from freak waves. Increasing the thickness of the breakwater and the number of breakwater stiffeners is recommended to guarantee local strength and avoid structural damage. 4. Equivalent static analysis methods are computationally efficient and widely applicable in engineering, but tend to produce conservative results, which may result in material waste. As such, they are best suited for the preliminary design stage of ship hulls. However, this study focuses on the high-speed water impact caused by freak waves, which is a transient dynamic problem. The equivalent static analysis methods cannot reflect the temporal and spatial differences in the green water impact phenomenon. Therefore, the dynamic analysis methods are more suitable for the analysis of such problems. 5. The linear dynamic analysis method can capture the spatial and temporal characteristics of slamming loads, but fails to account for geometric and material nonlinearity. It is best suited for scenarios where the slamming load is small and does not result in material failure. However, these methods cannot accurately reflect the state of structural damage or accurately describe the areas of the structure that have been damaged. The damaged areas determined by these methods are often overestimated. Therefore, if the stress response of the linear analysis methods exceeds the yield limit of the material, nonlinear dynamic analysis methods should be used. Nonlinear dynamic analysis methods can not only more accurately display the damaged areas and states of the structure, but also obtain more precise stress responses and displacement results of the structure. This study may contribute to the better understanding of ship safety design under freak-wave conditions. The green-water loads and corresponding structural analysis may be of reference value from an engineering point of view.