Method for predicting hydroelastic response of high-speed large monohull ship considering outboard slamming

Abstract

This invention discloses a method for predicting the hydroelastic response of high-speed large monohull vessels considering outward slamming. The method includes: constructing multiple coordinate systems adapted to the vessel's navigation state and profile analysis; obtaining core structural parameters and hydrodynamic coefficients by combining dry modal analysis and time-domain hydroelasticity theory; and obtaining a two-dimensional profile by cutting key areas of the hull. z The wave-making effect of the bow in still water at high speeds is determined by the shaft angle gauge; the relative motion parameters of the cross-section and the incident wave and the generalized slamming force are calculated; the time-domain hydroelasticity equations containing the slamming force are solved using an asynchronous coupling method and numerical solution technology to obtain the hydroelastic response results. This invention overcomes the limitations of low-speed applications, balances prediction accuracy and computational efficiency, does not rely on operator experience, has strong solution stability, and can be directly used for overall strength verification at different design stages of ships, providing reliable support for the safety assessment of structures related to slamming at high-speed ships.

Description

Technical Field

[0001] This invention relates to the field of ship design technology, and in particular to a method for predicting the hydroelastic response of high-speed large monohull ships that takes into account overhanging impacts. It is applicable to the assessment of structural loads caused by overhanging impacts on ships in medium sea states and can be applied to the overall strength verification of ship structures at different design stages. Background Technology

[0002] With the development of the shipbuilding industry, ships are trending towards larger sizes and lighter structures. This trend significantly increases the overall structural flexibility of ships, posing a severe challenge to the design and assessment of the overall structural strength of ships in harsh sea conditions. Among these challenges, the structural strength and safety of ships caused by slamming in the marine environment has always been a key research focus in the field of ship design. For large monohull vessels, the powerful impact pressure generated during a slamming event primarily acts on the bow and stern outward-flaring areas and the bottom, resulting in two forms: outward-flaring slamming and bottom slamming. Both can cause damage to localized hull structures. Outward-flaring slamming, in particular, can significantly increase the midship section load level, greatly increasing the risk of hull fracture. Therefore, accurate prediction of the load and structural response to outward-flaring slamming is crucial.

[0003] The methods for predicting ship slamming loads have undergone a gradual development process in the industry: In the 1980s and 1990s, the industry mostly used standard methods or empirical formulas to estimate slamming pressure; after entering the 21st century, with the improvement of computer computing power, the method of combining two-dimensional slamming theory with three-dimensional hydroelasticity theory was gradually applied, and this method has become the widely used method for predicting single-ship slamming loads in engineering; in recent years, the ship fluid-structure interaction assessment method based on the coupling of CFD software and finite element software has developed rapidly and has become a new direction for ship slamming load prediction, but this method is still in the exploratory stage and has not yet been maturely applied. Overall, current mainstream methods for predicting slamming loads on single-ship vessels are limited to low-speed conditions. While this aligns with the reality that ships are prone to slamming in severe sea states and typically reduce speed, it cannot address the high-speed conditions in moderate sea states. Ships traveling at high speeds in moderate sea states (generally considered to be in a high-speed condition when the Froude number is greater than 0.3) will also experience slamming effects, and their wave load levels will significantly increase. Existing methods are no longer applicable for predicting and assessing slamming loads under such conditions.

[0004] Meanwhile, the prediction of flutter response of large ships caused by slamming needs to take into account both the hydroelastic effect of the hull and the effect of slamming load. Existing prediction methods still have obvious shortcomings: on the one hand, prediction methods based on potential flow theory are only applicable to low-speed conditions and do not consider the influence of three-dimensional flow effects such as bow wave-making on slamming, so they cannot be used to evaluate the flutter response of the hull structure caused by slamming at high speeds; on the other hand, fluid-structure interaction methods based on viscous flow theory and structural dynamics theory require one-way or two-way coupling calculations using CFD and finite element software, which not only involves huge computational loads, but also makes the calculation accuracy overly dependent on the operating experience of the software users, making it difficult to widely apply to the evaluation of flutter response of ship structures in actual engineering.

[0005] Compared to the still-exploratory fluid-structure interaction method, the analysis method based on two-dimensional slamming theory combined with three-dimensional hydroelasticity has the advantages of high computational efficiency and stable results, making it more suitable for practical engineering design needs. Therefore, it is urgent to improve and optimize this method so that it can be effectively applied to the prediction of slamming loads and hydroelastic responses of large monohull ships at high speeds, while also considering the convenience of engineering applications and computational accuracy, and solving the aforementioned problems in existing technologies. Summary of the Invention

[0006] To address the aforementioned problems and technical requirements, the inventors have proposed a method for predicting the hydroelastic response of high-speed large monohull vessels that takes into account overhanging impacts. This method can effectively predict the structural flutter response of vessels under moderate sea states caused by high speeds and overhanging impacts. Furthermore, the method is simple, computationally efficient, and suitable for practical engineering applications. The technical solution of this invention is as follows:

[0007] A method for predicting the hydroelastic response of a high-speed large monohull vessel taking into account outward slamming impact includes the following steps: Construct a geodetic coordinate system, a balance coordinate system that travels with the ship, and a sectional coordinate system fixed to the ship's cross-section. Dry modal analysis was performed on the finite element model of the target hull structure in the equilibrium coordinate system to obtain the core structural parameters, including the deformation displacement vectors of the hull surface under each elastic mode. Based on the theory of time-domain hydroelasticity, the hydrodynamic coefficients of the structure are determined in the equilibrium coordinate system; By cutting through the key areas at the bow and stern of the target hull structure, two-dimensional hull sections are obtained, where the section coordinate system of the two-dimensional hull section at the bow is specified. z Axis and equilibrium coordinate system z The included angle of the shaft is determined taking into account the wave-making effect of the bow in still water at high speeds; Calculate the vertical relative displacement and relative entry velocity between the two-dimensional hull profile and the incident wave in the profile coordinate system, and use this to calculate the generalized slamming force in the equilibrium coordinate system. Based on the core structural parameters and hydrodynamic coefficients, a time-domain hydroelasticity equation containing generalized impact force is established. The equation is solved using an asynchronous coupling method and a numerical solution method to obtain the hydroelastic response prediction results of the target ship hull structure.

[0008] A further technical solution is that the method also includes: The deformation displacement vectors of the hull surface under each elastic mode are distributed to each node of the two-dimensional hull section according to the mesh correspondence, so as to obtain the deformation displacement at each node of the two-dimensional hull section. The rigid body motion displacements at each node of the two-dimensional hull section are derived based on the three-dimensional seakeeping theory. Together with the elastic deformation displacement, they constitute the complete displacement field of the two-dimensional hull section, which is used to calculate the position vector of each point of the two-dimensional hull section in the geodetic coordinate system and the generalized slamming force in the equilibrium coordinate system.

[0009] A further technical solution is that the included angle is determined taking into account the wave-making effect of the bow in still water at high speeds, including: The included angle is taken as the average wave surface inclination angle of the bow calm water wave generated by the target hull structure when it sails at high speed, and it increases with the increase of ship speed. The two-dimensional hull section at the stern is perpendicular to the still water wave surface, and its coordinate system is... z Axis and equilibrium coordinate system z The included angle of the axes is zero.

[0010] The beneficial technical effects of this invention are: 1. Adaptable to high-speed operating conditions: The slamming profile segmentation method proposed in this application requires the profile to be aligned with the calm water wave surface of the bow. z The axis has a certain angle (the value is taken to consider the average inclination angle of the wave surface of the bow in still water at high speed), which is perpendicular to the wave surface of the bow in still water at high speed. This is more in line with the two-dimensional slamming theory model, making the slamming force calculation results reasonable and effective. It breaks through the limitation of existing methods that are only applicable to low speeds, and realizes accurate prediction of the hydroelastic response related to the slamming of large monohull ships at high speeds in medium sea states.

[0011] 2. Improved Calculation Accuracy: By relying on multiple adapted coordinate systems, calculation of ship wave relative motion parameters, generalized impact force conversion, and asynchronous coupling, the error in load and response prediction is effectively reduced, and it does not rely on operator experience, thus solving the problem of insufficient accuracy and stability of existing fluid-structure interaction methods. The proposed method for calculating the relative ship wave entry velocity takes into account the bow wave-making effect caused by high speed, and also considers the contribution of high ship speed to the relative ship wave entry velocity.

[0012] 3. Balancing computational efficiency: By adopting time-domain hydroelasticity theory combined with numerical solution techniques, the massive computations required by traditional fluid-structure interaction methods are avoided. At the same time, through simplification strategies such as impulse equivalence, the computational efficiency of impact force and hydroelastic response is improved while ensuring accuracy, making it suitable for practical application needs in engineering design.

[0013] 4. Enhanced engineering practicality: The overall method and steps are clear, and key parameters can be flexibly determined through numerical calculation, experimental measurement or engineering experience. The section cutting and displacement mapping logic is adapted to the characteristics of ship structure and can be directly used for the overall strength verification of ships at different design stages. It has a wide range of applications and is easy to operate. Attached Figure Description

[0014] Figure 1 This is a flowchart of the method for predicting the hydroelastic response of high-speed large monohull ships that takes into account outward slamming, provided in this application. Figure 2 This is a schematic diagram of the geodetic coordinate system, equilibrium coordinate system, and profile coordinate system provided in this application; Figure 3 This is a schematic diagram of the included angle of a two-dimensional hull section located at the bow, provided in this application. Figure 4 This is a schematic diagram of a two-dimensional hull cross-section provided in this application; Figure 5 This is a schematic diagram of the deformation mapping of the two-dimensional hull cross-section structure provided in this application; Figure 6 This is a schematic diagram of bidirectional asynchronous coupling for impact calculation provided in this application. Detailed Implementation

[0015] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0016] Please refer to Figure 1 As shown, one embodiment of this application provides a method for predicting the hydroelastic response of a high-speed large monohull vessel considering outward slamming, specifically including the following steps: Step (0): Construct multiple coordinate systems adapted to the ship's navigation state and profile analysis. In this embodiment, the following three coordinate systems are required: 1) Geodetic coordinate system The geodetic coordinate system is fixed to the earth, with the origin at... Located on still water, The axis is perpendicular to the still water surface and points upwards, such as Figure 2 As shown.

[0017] 2) The equilibrium coordinate system that travels with the ship Origin of coordinates Located at the center of gravity of the target ship, x The axis points from the stern to the bow. The axis is perpendicular to the free plane and points upwards; this coordinate system moves with the target ship at a constant speed. along x Positive direction (i.e.) (Direction) navigation, and at the initial moment of the ship's motion, it coincides with the Earth's coordinate system, such as Figure 2 As shown.

[0018] 3) Section coordinate system : Fixed to the hull section and moving with the section, obtained from the equilibrium coordinate system through Euler coordinate transformation (Euler angle rotation and translation transformation). The axis aligns with the normal direction of the section and points towards the bow. Axis and equilibrium coordinate system y The axis is consistent; when the hull has no six degrees of freedom of motion and no deformation, its origin is... Located in the cross-section and equilibrium coordinate system x The intersection of the axes, such as Figure 2 As shown.

[0019] Step (1): Perform dry modal analysis on the finite element model of the target hull structure in the equilibrium coordinate system to obtain the core structural parameters. In this embodiment, the dry modal analysis selects several overall elastic modes after removing the six-degree-of-freedom rigid body modes. The core structural parameters include the generalized mass matrix of the structure. Generalized stiffness matrix And the deformation displacement vectors of the hull surface under each elastic mode. The dry modal analysis of the finite element model is a well-known technique in this field and will not be elaborated here.

[0020] Step (2): Using time-domain hydroelasticity theory, determine the hydrodynamic coefficients of the structure in the equilibrium coordinate system. In this embodiment, during the determination of the hydrodynamic coefficients, the first six generalized modes correspond to the six degrees of freedom rigid body motion of the ship: sway, roll, heave, pitch, pitch, and bow. The remaining... The first mode is an elastic mode. m This represents the total number of modes to be solved. The hydrodynamic coefficients include the additional mass matrix at infinite frequencies. Damping array caused by speed The restoring force caused by speed and the impulse response function of radiation wave force The impulse response function of the diffracted wave force under the top wave The process of determining the hydrodynamic coefficients is a well-known technique in this field and will not be elaborated here.

[0021] Step (3): Cut the key areas at the bow and stern of the target hull structure to obtain a two-dimensional hull profile.

[0022] The key areas of the hull are the hydrodynamic hull regions at the bow and stern, each representing one-quarter of the ship's length. The waterline sections are considered simultaneously during cutting. The section coordinate system for the two-dimensional hull section located at the bow is shown. Axis and equilibrium coordinate system z The included angle of the shaft is determined taking into account the wave-making effect of the bow in still water at high speeds. In this embodiment, the speed is taken into account. The contribution to the relative velocity of the ship waves is taken as the mean inclination angle of the bow wave generated by the target ship structure when it is sailing at high speed. β And it increases with the increase of ship speed, such as Figure 3 As shown; since there is no significant wave-making at the stern, the two-dimensional hull section at the stern is set perpendicular to the calm water wave surface, i.e., its section coordinate system is... Axis and equilibrium coordinate system z The included angle between the axes is zero, that is... .

[0023] Optionally, the average wave face in still water at the bow. β Values ​​can be obtained through numerical calculations, experimental measurements, or engineering experience (e.g.) The number of two-dimensional hull sections for each key area is set to approximately 20, such as... Figure 4 As shown.

[0024] Step (4): Obtain the mapped structural deformation and rigid body motion displacement of the two-dimensional hull section.

[0025] Specifically, the deformation displacement vectors of the hull surface under each elastic mode are... The deformation displacements at each node of the 2D hull section are obtained by assigning them to the corresponding nodes according to the mesh correspondence, such as... Figure 5 As shown in the figure, the T value represents the magnitude of the deformation displacement vector. The six-degree-of-freedom rigid body motion displacements at each node of the two-dimensional hull section can be derived based on the three-dimensional seakeeping theory. Together with the elastic deformation displacement, they constitute the complete displacement field of the two-dimensional hull section, which is used in subsequent steps to calculate the position vector of each point of the two-dimensional hull section in the geodetic coordinate system and the generalized slamming force in the equilibrium coordinate system.

[0026] Step (5): In the section coordinate system, calculate the two-dimensional hull section along the... Infinite frequency added mass at different immersion depths in the negative axis direction .calculate The method can be implemented by referring to existing calculation methods, and will not be elaborated here.

[0027] Step (6): Calculate the relative motion parameters between the two-dimensional hull profile and the incident wave in the profile coordinate system, and use these parameters to calculate the generalized slamming force in the equilibrium coordinate system. The relative motion parameters include the vertical relative displacement and the relative entry velocity. The specific calculation process is as follows: 1) The vertical relative displacement is obtained by modal superposition method to obtain the position vectors of each point on the two-dimensional hull profile and the water particle on the incident wave surface in the geodetic coordinate system. After vector subtraction, the position vectors are obtained along the profile coordinate system. Obtained by axis projection. Specifically, the points of the two-dimensional hull section are obtained through modal superposition. Position vector in geodetic coordinate system Simultaneously calculate each point of the two-dimensional hull section. Projection point on the incident wave surface (i.e., water particles incident on the wave surface), and Position vector in geodetic coordinate system , respectively represented as:

[0028]

[0029] in, The coordinates of the origin of the equilibrium coordinate system in the geodetic coordinate system; On the cross section The first point First-order modal displacement vector; For the first First modal principal coordinates; for The coordinates of the point in the equilibrium coordinate system, and for The incident wavefront rises at that point.

[0030] The relative displacement vector is determined by and Subtracting the values ​​yields the result, which is then plotted along the cross-sectional coordinate system. Projecting along the axis, we obtain the lowest point of the profile and the incident wave in the profile coordinate system. Vertical relative displacement on the axis :

[0031] in, For the section coordinate system The axis is the unit direction vector in the geodetic coordinate system.

[0032] 2) Relative entry velocity is based on vertical relative displacement. The calculation of the mass derivative, while taking into account the ship's speed. The effect on the relative motion of the ship waves is expressed as:

[0033] in, This is the matter derivative.

[0034] 3) The specific process for calculating the generalized slamming force in the equilibrium coordinate system includes: determining the occurrence of a slamming event based on the relative entry velocity condition determined by the Ochi formula and the distance condition where the lowest point of the two-dimensional hull profile is below the incident wave surface. The two conditions are as follows:

[0035] in, This is the length between the ship's perpendiculars; This is the acceleration due to gravity.

[0036] If the relative velocity condition or the distance condition does not hold, let the first... The impact force of a cross section Conversely, if both the relative velocity and distance conditions are met, then the relative entry velocity and the added mass at infinite frequency will be considered. The momentum slamming theory is used to calculate the coordinate system along the two-dimensional hull section. The axial section impact force is then transformed into a generalized impact force in the equilibrium coordinate system.

[0037] Among them, the second hull section A section along the section coordinate system The axial section impact force is:

[0038] The 1st digit in the equilibrium coordinate system is further obtained using the following formula. The generalized impact force of the first mode is:

[0039] in, For the first The first section The first modal displacement vector is obtained by using the least squares method from the modal displacement vectors of each node in the section submerged below the incident wave surface; For the first The thickness of each section.

[0040] Step (7): Based on the core structural parameters and hydrodynamic coefficients, establish the time-domain hydroelasticity equations containing the generalized impact force. Solve the equations using an asynchronous coupling method and numerical solution method to obtain the predicted hydroelastic response of the target hull structure. Combined with Figure 6 As shown, this step specifically includes the following: ① First, establish the time-domain hydroelasticity equations considering the impact force:

[0041] in, These are the principal modal coordinates, also known as generalized displacements. and These are generalized velocity and generalized acceleration, respectively. and These are the generalized incident wave force and the hydrostatic restoring force, respectively, obtained by pressure integration on the instantaneous surface below the incident wave plane; For generalized gravity, For generalized impact force; To balance the rise of the incident wavefront at the origin of the coordinate system, For integration variables characterizing time; It is an artificial damping array. It is an artificial spring stiffness matrix.

[0042] ② Generalized incident wave force of the right-hand side of the equation and still water resilience Only at the initial moment of each computation time step Please provide a solution.

[0043] ③ When calculating the generalized impact force, it is necessary to adjust the time step of the equation calculation. Divide into several sub-steps (e.g., into several sub-steps) N (segment), and assume the entire computation time step. If the internal generalized acceleration remains constant, then Within a time period (i.e., one Generalized displacement and generalized velocity can be written as:

[0044] From that moment on, the generalized impact force is calculated sequentially in each sub-step using the calculation method provided in step (6). until reached The moment is determined by summing the impulses within each sub-time step using the impulse equivalence method, resulting in the equivalent impact force for the entire time step:

[0045] ④ The fourth-order Runge-Kutta method is used to numerically solve the time-domain hydroelasticity equations, with each calculation time step... The set sub-time point, that is, at each sub-time point , , and Solving for the modal principal coordinate response at each time step, and then performing weighted calculations to obtain the endpoint time of each calculation time step (i.e., generalized displacement With generalized speed Continue until the calculation is complete.

[0046] The above descriptions are merely preferred embodiments of this application, and the present invention is not limited to the above embodiments. It is understood that other improvements and variations directly derived or conceived by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included within the protection scope of the present invention.

Claims

1. A method for predicting the hydroelastic response of a high-speed large monohull vessel considering outward slamming impact, characterized in that, The method includes: Construct a geodetic coordinate system, a balance coordinate system that travels with the ship, and a sectional coordinate system fixed to the ship's cross-section. Dry modal analysis was performed on the finite element model of the target hull structure in the equilibrium coordinate system to obtain the core structural parameters, including the deformation displacement vectors of the hull surface under each elastic mode. Based on the theory of time-domain hydroelasticity, the hydrodynamic coefficients of the structure are determined in the equilibrium coordinate system. By cutting through the key areas at the bow and stern of the target hull structure, two-dimensional hull sections are obtained, where the section coordinate system of the two-dimensional hull section at the bow is specified. z Axis and equilibrium coordinate system z The included angle of the shaft is determined taking into account the wave-making effect of the bow in still water at high speeds; Calculate the vertical relative displacement and relative entry velocity between the two-dimensional hull profile and the incident wave in the profile coordinate system, and use this to calculate the generalized slamming force in the equilibrium coordinate system. Based on the core structural parameters and hydrodynamic coefficients, a time-domain hydroelasticity equation containing generalized impact force is established. The equation is solved using an asynchronous coupling method and a numerical solution method to obtain the hydroelastic response prediction results of the target ship structure.

2. The method for predicting the hydroelastic response of high-speed large monohull ships considering outward slamming impact as described in claim 1, characterized in that, The calculation of the vertical relative displacement and relative entry velocity between the two-dimensional hull profile and the incident wave in the aforementioned profile coordinate system includes: The vertical relative displacement is obtained by modal superposition method to obtain the position vectors of each point on the two-dimensional hull profile and the water quality point on the incident wave surface in the geodetic coordinate system, and then obtained by subtracting the vectors and projecting them along the z-axis of the profile coordinate system. The relative entry velocity is calculated based on the vertical relative displacement and the mass derivative, while also taking into account the influence of the ship's speed on the relative motion of the ship waves.

3. The method for predicting the hydroelastic response of high-speed large monohull ships taking into account outward slamming impact as described in claim 1, characterized in that, Calculating the generalized impact force in the equilibrium coordinate system includes: The occurrence of a slam is determined based on the relative entry velocity condition determined by the Ochi formula and the distance condition that the lowest point of the two-dimensional hull profile is located below the incident wave surface. When both conditions are met, the section impact force of the two-dimensional hull section along the z-axis of the section coordinate system is calculated by combining the relative entry velocity and the infinite frequency added mass of the two-dimensional hull section at different immersion depths, and then transformed into the generalized impact force in the equilibrium coordinate system.

4. The method for predicting the hydroelastic response of high-speed large monohull ships considering outward slamming impact as described in claim 2, characterized in that, Points of a two-dimensional hull section Position vector in the geodetic coordinate system Represented as: The incident wave surface water quality points are each point on the two-dimensional hull profile. Projection point on the incident wave surface , Position vector in the geodetic coordinate system Represented as: in, The coordinates of the origin of the equilibrium coordinate system in the geodetic coordinate system; On the cross section The first point First-order modal displacement vector, m To determine the total number of modes; For the first First modal principal coordinates; for The coordinates of the point in the equilibrium coordinate system, and for The incident wavefront rises at that point.

5. The method for predicting the hydroelastic response of high-speed large monohull ships taking into account outward slamming impact as described in claim 3, characterized in that, The first in the equilibrium coordinate system The generalized impact force of the first mode is: in, For the first The first section First-order modal displacement vector, For the section coordinate system z The axis is the unit direction vector in the geodetic coordinate system. For the calculated two-dimensional hull section, the first A section along the section coordinate system z Axial sectional impact force. For the first The thickness of each section, m To determine the total number of modes.

6. The method for predicting the hydroelastic response of high-speed large monohull ships taking into account outward slamming as described in any one of claims 1-3, characterized in that, The method further includes: The deformation displacement vectors of the hull surface under each elastic mode are distributed to each node of the two-dimensional hull section according to the mesh correspondence, so as to obtain the deformation displacement at each node of the two-dimensional hull section. The rigid body motion displacements at each node of the two-dimensional hull profile are derived based on the three-dimensional seakeeping theory. Together with the elastic deformation displacement, they constitute the complete displacement field of the two-dimensional hull profile, which is used to calculate the position vector of each point of the two-dimensional hull profile in the geodetic coordinate system and the generalized slamming force in the equilibrium coordinate system.

7. The method for predicting the hydroelastic response of high-speed large monohull ships considering outward slamming impact as described in claim 1, characterized in that, The included angle is determined taking into account the wave-making effect of the bow in still water at high speeds, including: The included angle is taken as the average wave surface inclination angle of the bow calm water wave generated by the target hull structure when it sails at high speed, and it increases with the increase of ship speed. The two-dimensional hull section at the stern is perpendicular to the still water wave surface, and its coordinate system is... z Axis and equilibrium coordinate system z The included angle of the axes is zero.

8. The method for predicting the hydroelastic response of high-speed large monohull ships considering outward slamming impact as described in claim 1, characterized in that, The time-domain hydroelastic equation containing the generalized impact force is expressed as follows: in, For the generalized mass matrix, is the generalized stiffness matrix, which belongs to the core parameters of the structure; These are the principal modal coordinates, also known as generalized displacements. and These are generalized velocity and generalized acceleration, respectively. Add a mass array at infinite frequencies. The damping array is caused by the speed of the ship. The restoring force caused by speed, Let be the impulse response function of the radiation wave force. The impulse response function of the diffracted wave force under the top wave is a function of the hydrodynamic coefficients. and These are the generalized incident wave force and the hydrostatic restoring force, respectively, obtained by pressure integration on the instantaneous surface below the incident wave plane; For generalized gravity, For generalized impact force; The incident wavefront at the origin of the equilibrium coordinate system is raised. For integration variables characterizing time; It is an artificial damping array. It is an artificial spring stiffness matrix.

9. The method for predicting the hydroelastic response of high-speed large monohull ships considering outward slamming impact as described in claim 8, characterized in that, The method of solving the equations using asynchronous coupling and numerical solution yields the predicted hydroelastic response of the target ship structure, including: The calculation time step of the equation is divided into several sub-steps, and it is assumed that the generalized acceleration remains constant throughout the entire calculation time step. The generalized incident wave force and hydrostatic restoring force are solved only at the initial moment of each computation time step; The method of calculating the generalized slamming force in the equilibrium coordinate system is adopted by calculating the vertical relative displacement and relative water entry velocity of the two-dimensional hull profile and the incident wave in the cross-sectional coordinate system. The generalized slamming force is calculated in each sub-step, and the equivalent slamming force of the entire time step is obtained by accumulating the impulse of the sub-step through the impulse equivalence method. The numerical solution method adopts the fourth-order Runge-Kutta method, which solves the modal principal coordinate response at a set sub-time point of each calculation time step, and obtains the generalized displacement and generalized velocity at the end time of each calculation time step through weighted calculation.

10. The method for predicting the hydroelastic response of a high-speed large monohull vessel considering outward slamming impact as described in claim 1, characterized in that, The geodetic coordinate system is fixed to the earth, with its origin located on the still water surface and z The axis is perpendicular to the still water surface and faces upwards; The origin of the equilibrium coordinate system is located at the center of gravity of the target ship. x The axis points from the stern to the bow, and the equilibrium coordinate system moves along the target hull at a constant speed. x The ship is sailing in the positive direction and coincides with the Earth's coordinate system at the initial moment of its motion; The profile coordinate system is obtained from the equilibrium coordinate system through Euler angle rotation and translation transformation. x The axis aligns with the normal direction of the section and points towards the bow. y Axis and the equilibrium coordinate system y When the hull has no six degrees of freedom motion and no deformation, its origin is located at the intersection of the cross-section and the equilibrium coordinate system. x The intersection of the axes.

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