Underwater dynamic simulation method for navigation body and related equipment

Abstract

The embodiment of the invention discloses a navigation body effluent dynamics simulation method and related equipment, which can accurately simulate the complex interaction between fluid and solid when a navigation body exits water by establishing a physical model and a coupling strategy; and a proper control equation and solver are arranged, so that the dynamic change of the fluid domain can be accurately processed. The fluid domain is subjected to grid division and data exchange interface definition, and fluid details can be carefully captured; boundary conditions, initial conditions and motion modes are defined, and various actual working conditions can be comprehensively simulated. Simulation is carried out based on the conditions, rich and accurate data can be obtained, the dynamic performance of the navigation body when the navigation body is out of water can be accurately predicted, and the performance and safety of the navigation body are improved.

Description

Technical Field

[0001] This invention relates to the field of water exit simulation technology, and in particular to a method and related equipment for simulating the dynamics of a vehicle exiting water. Background Technology

[0002] Vertical emergence of a vehicle from the water is a typical cross-medium, highly transient, and highly nonlinear fluid-structure interaction (FSI) dynamic process. This process involves two fluids, water and air, with vastly different densities and viscosities, resulting in dramatic free surface deformation, cavitation evolution, fluid phase transitions, and the structural dynamic response of the vehicle itself. The strong interaction between the fluid and the structure (FSI) is crucial in determining the vehicle's emergence attitude, load, stability, and structural safety.

[0003] Traditional methods for studying the emergence of aircraft carriers rely heavily on theoretical derivations or small-scale experiments. Theoretical derivations often simplify real-world problems, making it difficult to accurately reflect real-world conditions under complex circumstances. Small-scale experiments, limited by experimental conditions and costs, cannot comprehensively simulate various real-world scenarios and yield limited data. This makes it difficult to accurately predict the dynamic performance of an aircraft carrier during the design phase, potentially leading to instability and structural damage during actual emergence, thus affecting its performance and safety. Summary of the Invention

[0004] In view of this, the present invention provides a method and related equipment for simulating the dynamics of a vehicle emerging from the water.

[0005] The specific technical solution of the first embodiment of the present invention is as follows: a method for simulating the dynamics of a vehicle emerging from the water, the method comprising: establishing a physical model and coupling strategy for simulating the dynamics of a vehicle emerging from the water; setting the control equations and solver for simulating the dynamics of a vehicle emerging from the water; dividing the fluid domain for simulating the dynamics of a vehicle emerging from the water and defining the data exchange interface; defining the boundary conditions, initial conditions and motion modes for simulating the dynamics of a vehicle emerging from the water; and performing dynamics simulation of the vehicle emerging from the water based on the physical model, the coupling strategy, the control equations, the solver, the divided mesh, the data exchange interface, the boundary conditions, the initial conditions and the motion modes.

[0006] Preferably, the coupling strategy adopts a bidirectional tight coupling algorithm. In each co-simulation time step, the fluid pressure and shear force are transmitted to the preset structural analysis software as external loads to calculate the structural deformation of the vehicle during the water exit process. After calculating the structural deformation, the displacement and velocity of the vehicle are fed back to the fluid to update the mesh and boundary of the fluid domain.

[0007] Preferably, the physical model includes a multiphase flow model, a turbulence model, a cavitation model, and a vehicle structure model.

[0008] Preferably, the cavitation model is obtained using the following formula:

[0009]

[0010] in, Evaporation rate For condensation rate, The density of the vapor phase is... The density of the liquid, This represents the volume fraction of steam. Cavitation radius, It is the saturated vapor pressure. Local pressure.

[0011] Preferably, the governing equations include fluid domain governing equations and structural domain governing equations; the fluid domain governing equations include mixed phase mass conservation equations, momentum conservation equations, and VOF phase fractional transport equations; the structural domain governing equations include equilibrium equations.

[0012] Preferably, the mass conservation equation for the mixed phase is obtained using the following formula: The momentum conservation equation is obtained using the following formula: The VOF phase fractional transport equation is obtained using the following formula: ;in, For fluid density, For time, Let i be the component of the velocity vector in the i-direction. Let be the component of the velocity vector in the j-direction. Let i be the spatial coordinate in the direction of i. Let j be the spatial coordinate in the j-direction. For fluid pressure, The dynamic viscosity of the fluid. For turbulent viscosity, This represents the component of the gravitational acceleration vector in the i-direction; The volume fraction of phase q within the control unit, 0 ≤ ≤1, when When =0, the control unit is full of water. When =1, the control unit is filled with air; when 0 < When <1, the control unit is located at the interface between the two phases. Let be the component of the velocity vector in the j-direction. For interphase quality transmission rate, Let q be the density of phase q.

[0013] Preferably, the equilibrium equation is obtained using the following formula:

[0014] in, For Cauchy stress tensor, Let be the divergence of the stress tensor. The volume force acting on the ship. For the density of the carrier, Let be the component of the acceleration vector in the i-direction.

[0015] The specific technical solution of the second embodiment of the present invention is as follows: a simulation system for the dynamics of a vehicle emerging from the water, the system comprising: a model and strategy construction module, a control and solution module, a first definition module, a second definition module, and a simulation module; the model and strategy construction module is used to establish the physical model and coupling strategy for the dynamics simulation of the vehicle emerging from the water; the control and solution module is used to set the control equations and solver for the dynamics simulation of the vehicle emerging from the water; the first definition module is used to perform mesh generation and data exchange interface definition for the fluid domain in the dynamics simulation of the vehicle emerging from the water; the second definition module is used to define the boundary conditions, initial conditions, and motion modes in the dynamics simulation of the vehicle emerging from the water; the simulation module is used to perform dynamics simulation of the vehicle emerging from the water based on the physical model, the coupling strategy, the control equations, the solver, the mesh, the data exchange interface, the boundary conditions, the initial conditions, and the motion modes.

[0016] The specific technical solution of the third embodiment of the present invention is as follows: a simulation device for the dynamics of a vehicle emerging from the water, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method as described in any one of the first embodiments of this application.

[0017] The specific technical solution of the fourth embodiment of the present invention is as follows: a computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor performs the steps of the method as described in any one of the first embodiments of this application.

[0018] Implementing the embodiments of the present invention will have the following beneficial effects: This invention, through the establishment of a physical model and coupling strategy, can accurately simulate the complex interactions between fluid and solid components when a vehicle emerges from the water. By setting appropriate governing equations and solvers, it can accurately handle the dynamic changes in the fluid domain. Mesh generation and data exchange interface definition of the fluid domain can meticulously capture fluid details; defining boundary conditions, initial conditions, and motion modes allows for comprehensive simulation of various real-world operating conditions. Simulations based on these conditions can obtain rich and accurate data, precisely predicting the dynamic performance of the vehicle upon emergence from the water, thus improving the vehicle's performance and safety. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 Flowchart of the steps in the simulation method for the dynamics of a vehicle emerging from the water; Figure 2 Schematic diagram of the vertical water exit grid of the aircraft carrier; Figure 3a Phase cloud diagram of the vertical emergence of the vehicle from the water; Figure 3b Pressure cloud diagram of the vertical exit process of the aircraft body; Figure 3c Diagram of cavitation morphology during the vertical exit of the vehicle from the water; Figure 4a : Cloud map of stress distribution when the aircraft leaves the water vertically; Figure 4b : Elastic strain distribution cloud map of the vertical exit of the water of the aircraft body; Figure 5 : Time-varying curve of vertical water exit stress of the aircraft body; Figure 6 Schematic diagram of the structure of the water exit dynamics simulation system for a vehicle; Figure 7 Internal structure diagram of computer equipment; The module consists of: 201. Model and strategy construction module; 202. Control and solution module; 203. First definition module; 204. Second definition module; and 205. Simulation module. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0022] The terms "first," "second," etc., used in the specification, claims, and drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or modules is not limited to the listed steps or modules, but may optionally include steps or modules not listed, or may optionally include other steps or modules inherent to such processes, methods, products, or apparatus.

[0023] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0024] Please see Figure 1 The above is a flowchart of the steps of the simulation method for the water-emerging dynamics of a vehicle in the first embodiment of this application, which aims to improve the performance and safety of the vehicle. The method includes: Step 101: Establish the physical model and coupling strategy for the dynamic simulation of the vehicle emerging from the water; Step 102: Set the control equations and solver for the dynamic simulation of the vehicle's exit from the water; Step 103: Mesh the fluid domain and define the data exchange interface for the dynamic simulation of the vehicle's exit from the water. Step 104: Define the boundary conditions, initial conditions, and motion modes for the dynamic simulation of the vehicle emerging from the water; Step 105: Perform water exit dynamics simulation of the vehicle based on the physical model, the coupling strategy, the control equations, the solver, the divided mesh, the data exchange interface, the boundary conditions, the initial conditions, and the motion mode.

[0025] Specifically, considering the structural characteristics of the aircraft and its exit environment, a physical model is established that includes the solid structure of the aircraft and the surrounding fluid field. A two-way fluid-structure interaction (FSI) strategy is adopted, where fluid pressure acts on the aircraft structure, causing it to deform, and the deformation of the aircraft structure, in turn, affects the fluid flow, thus accurately simulating the interaction between the two. An implicit unsteady solver is used in the fluid domain, and a dynamic implicit solver is used in the solid domain. The two are synchronized in time step through a co-simulation engine to achieve coupled solution of the governing equations. The fluid domain uses a cut-volume mesh, with local refinement in the free surface region, the aircraft's trajectory, and the near-wall region. Prismatic mesh layers are set on the aircraft wall to ensure that the y+ value is between 30 and 300. The structural domain is discretized using S4R shell elements. The wetted surface of the aircraft is defined as the FSI interface, ensuring a one-to-one correspondence between the nodes of the fluid and structural meshes at the interface. Linear interpolation is used for flow field data exchange between the overlapping mesh region and the background domain. The outer boundary of the fluid domain is set as a pressure outlet, and the bottom can be set as the wall or a pressure outlet. The flow field is initialized, and the hydrostatic pressure gradient and water phase distribution are defined using piecewise linear functions. The initial launch depth and velocity of the vehicle are defined. Its motion is achieved in two ways: 1) For vehicles requiring fluid-structure interaction analysis, the motion is calculated by a solid-state solver based on fluid loads and self-constraints; 2) For vehicles with a rigid body assumption, their six-degree-of-freedom motion is defined using a fluid DFBI model and applied force functions. Co-simulation is initiated. The motion parameters, hydrodynamic loads, cavitation morphology, free surface changes, and structural stress-strain distribution of the vehicle are monitored and recorded in real time. After the calculation is completed, the peak load, structural dynamic response, and cavitation evolution during the water exit process are analyzed.

[0026] The method in this embodiment, through the establishment of a physical model and coupling strategy, can accurately simulate the complex interactions between fluid and solid during the emergence of a vehicle from the water. By setting appropriate governing equations and solvers, it can accurately handle the dynamic changes in the fluid domain. Mesh generation and data exchange interface definition of the fluid domain can meticulously capture fluid details; defining boundary conditions, initial conditions, and motion modes can comprehensively simulate various actual operating conditions. Simulations based on these conditions can obtain rich and accurate data, accurately predict the dynamic performance of the vehicle during emergence, and improve the vehicle's performance and safety.

[0027] Specifically, the coupling strategy employs a bidirectional tightly coupled algorithm. Within each co-simulation time step, fluid pressure and shear force are transmitted to a pre-defined structural analysis software as external loads to calculate the structural deformation of the vehicle during its emergence from the water. After calculating the structural deformation, the displacement and velocity of the vehicle are fed back to the fluid to update the mesh and boundaries of the fluid domain. This bidirectional tightly coupled algorithm accurately transmits data between the fluid and solid within each co-simulation time step, ensuring that fluid pressure and shear force act on the vehicle structure promptly and accurately, and that structural deformation is quickly fed back to the fluid domain. This avoids the data transmission delays and errors inherent in traditional coupling methods, thereby significantly improving the accuracy of the simulation results.

[0028] In a specific embodiment, the physical model includes a multiphase flow model, a turbulence model, a cavitation model, and a vehicle structure model.

[0029] In a specific embodiment, the multiphase flow model employs the fluid volume method to accurately capture the dynamic evolution of the water-gas-steam three-phase interface.

[0030] In a specific embodiment, the Realizable k-ε model is selected as the turbulence model, in which the turbulent viscosity coefficient Cμ is a function of the strain tensor and the vorticity tensor, in order to avoid negative Reynolds stress and to more accurately simulate the complex shear flow during the water exit process of the vehicle.

[0031] The material constitutive model of the aircraft can be defined as a linear elastic model or an elastoplastic model according to the actual structural characteristics. When the aircraft is a rigid body, a rigid body motion model is adopted.

[0032] Both the background area and the overlapping mesh area use cut volume meshes or polyhedral meshes to improve mesh quality and computational efficiency.

[0033] In a specific embodiment, the cavitation model is obtained using the following formula:

[0034]

[0035] in, Evaporation rate For condensation rate, The density of the vapor phase is... The density of the liquid, This represents the volume fraction of steam. Cavitation radius, It is the saturated vapor pressure. Local pressure.

[0036] Overlapping mesh technique: This technique is enabled to set the aircraft as overlapping regions to handle its large six-degree-of-freedom vertical displacement motion. A structural model of the aircraft is established within the structure, and a Johnson-Cook plastic dynamic constitutive model is defined for it, with the following constitutive relations:

[0037] in, For flow stress, For equivalent plastic strain, The strain rate is dimensionless. The temperature is dimensionless. It is a material constant to accurately reflect the dynamic response of the material under high-pressure pulse load during cavitation collapse.

[0038] In a specific embodiment, the governing equations include fluid domain governing equations and structural domain governing equations; the fluid domain governing equations include mixed phase mass conservation equations, momentum conservation equations, and VOF phase fractional transport equations; the structural domain governing equations include equilibrium equations.

[0039] In a specific embodiment, the mass conservation equation for the mixed phase is obtained using the following formula: ; The momentum conservation equation is obtained using the following formula: ; The fractional transport equation for the VOF phase is obtained using the following formula: ; in, For fluid density, For time, Let i be the component of the velocity vector in the i-direction. This is the component of the velocity vector in the j-direction (in multiphase flow, this may refer to the velocity of the mixture or the phase velocity). Let i be the spatial coordinate in the direction of i. Let j be the spatial coordinate in the j-direction. For fluid pressure, The dynamic viscosity of the fluid. For turbulent viscosity, This represents the component of the gravitational acceleration vector in the i-direction; The volume fraction of phase q within the control unit, 0 ≤ ≤1, when When =0, the control unit is full of water. When =1, the control unit is filled with air; when 0 < When <1, the control unit is located at the interface between the two phases. Let be the component of the velocity vector in the j-direction. The interphase mass transfer rate (the mass per unit volume that is transferred from one phase to another phase q per unit time). Let q be the density of phase q.

[0040] In a specific embodiment, the equilibrium equation is obtained using the following formula:

[0041] in, Cauchy stress tensor describes the internal force (stress) per unit area inside a solid. Let be the divergence of the stress tensor, and let represent the net stress (i.e., the resultant force). The volume force is the force acting on a unit volume of a solid. The density of the solid. Let be the component of the acceleration vector in the i-direction.

[0042] The method in this embodiment achieves a balance between the accuracy of fluid-structure interaction simulation and its practicality in engineering: by using software co-simulation, it not only ensures the high fidelity of the physical model, but also encapsulates the complex coupling theory into an operable engineering process, greatly reducing the threshold for using high-precision simulation technology.

[0043] Breakthrough in the technical bottleneck of cross-medium transient dynamics simulation: Through the combination of "VOF + cavitation + overlapping grid + two-way tight coupling", a series of problems such as multiphase flow interface capture, phase change simulation, large motion grid processing and nonlinear coupling are systematically solved, which can accurately reproduce the complete physical process of the vehicle emerging from the water.

[0044] The flow field domain employs volume mesh generation and overlapping mesh calculation methods, while the structural domain uses surface mesh generation and shell element solution strategies. For example... Figure 2As shown, the background and overlapping domains of the flow field were generated using STAR-CCM+ software, with sparser and more precise cut-body elements respectively. To ensure stable mesh interpolation between the dynamic and static domains and good capture of free surface dynamics, local refinement was applied to the background and water surface. The refinement areas for the background and water surface were 4D×4D×5L and 20D×20D×0.25L cuboids, respectively, with a mesh size of 12.5%D for both. To simulate boundary layer flow, a prismatic layer mesh with a total thickness of 5%D, 25 layers, and an elongation of 1.25 was set near the vehicle wall. The mean y+ value of its surface was within 40~100, which met the calculation requirements of the selected turbulence model. Simultaneously, local refinement was applied around the vehicle to ensure a uniform transition between the boundary layer and overlapping domain meshes. The refinement mesh size was 2.5%D, meaning the mesh size on the vehicle surface was 0.02m. Here, x, y, and z are the directions of the three axes, corresponding to the positive directions of horizontal to the right, vertical upward, and downward, respectively. In the ijk coordinate system, i, j, and k correspond to the polar axis, radius, and height, respectively, with the same meaning as in the xyz coordinate system. The ijk coordinate system is derived from the polar coordinate transformation corresponding to the xoy plane, and can be converted to and from the Cartesian coordinate system through a certain function transformation.

[0045] like Figure 3a , Figure 3b and 3c The diagram shows the liquid phase, vapor phase, and pressure distribution cloud map, as well as the three-dimensional morphology and velocity vector distribution of the cavitation bubble during the water exit process when the launch velocity is 35 m / s (σ=0.24, Fr=5.1). The red arrows indicate the movement position of the return jet at the end of the cavitation bubble.

[0046] As can be seen from the pressure cloud map, during underwater movement, significant high-pressure peaks appear at the center of the head and tail, while localized low-pressure areas appear in the transition zone between the shoulder and tail contours. Comparing this to the phase distribution cloud map, it can be observed that significant cavitation occurs at these locations, with the cavitation bubbles filled entirely with water vapor. The outer edges of the bubbles, due to contact with the water, are in a vapor-liquid two-phase mixed state. From 40 to 160 ms, the shoulder cavitation bubbles gradually grow from the shoulder towards the tail, while the jet stream from the bubble tips travels in the opposite direction along the surface of the vehicle. At T=160 ms, the head of the vehicle reaches the free surface, causing a slight bulge and forming a "water mound" phenomenon. Simultaneously, the tips of the shoulder and tail cavitation bubbles detach and collapse, transitioning from a vapor phase to a vapor-liquid mixed state. From 160 to 185 ms, the fluid near the water surface abruptly changes from liquid to gas, thus reducing the medium density and consequently the environmental pressure. This causes the cavitation bubble tips to expand and collapse, gradually forming a propulsive collapse towards the tail under the force of the water surface. At T=195ms, the cavitation bubble collapses entirely under the pressure of the water surface and the back jet.

[0047] like Figure 4a and Figure 4bThis figure reflects the distribution of stress and elastic strain of the aircraft during the cavitation collapse phase. The figure shows that the stress and strain in the cavitation collapse zone are distributed in a ring-like pattern, with stress-strain circles radiating outward from each extreme point and spreading and merging into larger areas. This is because stress concentration occurs at the deformation points on the surface of the aircraft during cavitation collapse, forming multiple collapse points. As the elastic deformation recovers, the stress wave energy gradually neutralizes within the material. The peak values ​​of stress and elastic strain are 61.32 MPa and 0.5522 × 10⁻³, respectively. The collapse time is 198 ms, and the collapse axial position is 1.563 m, which basically coincides with the location of the cavitation collapse end.

[0048] Figure 5 For the monitoring point on the left side of the vehicle body where the stress peak is the largest, the stress-strain curves as a function of time during the cavitation development stage were plotted. As the pressure peak at each monitoring point gradually increases, the stress-strain peaks also rise accordingly. At T = 42.5 ms, 60 ms, 72.5 ms, and 90 ms, the pressure, stress, and elastic strain on the surface of the vehicle body are all at their peaks, showing consistency. At T = 50 ms, 80 ms, and 95 ms, the stress and strain are all at their troughs. The elastic strain at monitoring points 17 and 21 is approximately -0.025 × 10⁻³, and the stress is approximately 2 MPa. Observation of the graph reveals a secondary large peak in elastic strain. This is because under the impact of the pressure peak, the surface of the vehicle body deforms along the direction of the force. Due to the elasticity of the structure, as the pressure decreases, the deformation gradually recovers and produces deformation in the opposite direction of the force. Therefore, during the next pressure peak impact, the reverse deformation plays a certain role in buffering and absorbing energy, weakening the elastic strain peak.

[0049] In a specific embodiment, please refer to Figure 6 This is a schematic diagram of the structure of the vehicle emergence dynamics simulation system in the second embodiment of this application. The system includes: a model and strategy construction module 201, a control and solver module 202, a first definition module 203, a second definition module 204, and a simulation module 205. The model and strategy construction module 201 is used to establish the physical model and coupling strategy for the vehicle emergence dynamics simulation. The control and solver module 202 is used to set the control equations and solver for the vehicle emergence dynamics simulation. The first definition module 203 is used to perform mesh generation and define the data exchange interface for the fluid domain in the vehicle emergence dynamics simulation. The second definition module 204 is used to define the boundary conditions, initial conditions, and motion modes for the vehicle emergence dynamics simulation. The simulation module 205 is used to perform vehicle emergence dynamics simulation based on the physical model, the coupling strategy, the control equations, the solver, the mesh, the data exchange interface, the boundary conditions, the initial conditions, and the motion modes.

[0050] The system in this embodiment, through the establishment of a physical model and coupling strategy, can accurately simulate the complex interactions between fluid and solid during the emergence of a vehicle from the water. By setting appropriate governing equations and solvers, it can accurately handle the dynamic changes in the fluid domain. Mesh generation and data exchange interface definition of the fluid domain can meticulously capture fluid details; defining boundary conditions, initial conditions, and motion modes allows for comprehensive simulation of various real-world operating conditions. Simulations based on these conditions can obtain rich and accurate data, precisely predicting the dynamic performance of the vehicle during emergence, thereby improving the vehicle's performance and safety.

[0051] In a specific embodiment, the third embodiment of this application provides a simulation device for the dynamics of a vehicle emerging from the water, including a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method as described in any one of the first embodiments of this application.

[0052] In a specific embodiment, the fourth embodiment of this application provides a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the method as described in any one of the first embodiments of this application.

[0053] Figure 7 An internal structural diagram of a computer device in one embodiment is shown. This computer device can specifically be a terminal or a server. Please refer to... Figure 7 The computer device includes a processor, memory, etc., connected via a system bus. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and may also store a computer program. When executed by the processor, this computer program causes the processor to implement the method described in this embodiment. The internal memory may also store a computer program, which, when executed by the processor, causes the processor to perform the method described in this embodiment. Those skilled in the art will understand that... Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0054] The above embodiments merely illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A simulation method for the dynamics of a ship emerging from the water, characterized in that, The method includes: Establish the physical model and coupling strategy for the dynamic simulation of the water-emerging hull; Set the control equations and solver for the dynamic simulation of the water exit of the aircraft body; Mesh generation and data exchange interface definition are performed for the fluid domain during the dynamic simulation of the water exiting the vessel. Define the boundary conditions, initial conditions, and motion modes for the dynamic simulation of the vehicle emerging from the water; The dynamics simulation of the vehicle emerging from the water is performed based on the physical model, the coupling strategy, the control equations, the solver, the divided mesh, the data exchange interface, the boundary conditions, the initial conditions, and the motion mode.

2. The simulation method for the dynamics of a ship emerging from the water as described in claim 1, characterized in that: The coupling strategy employs a bidirectional tight coupling algorithm. In each co-simulation time step, fluid pressure and shear force are transmitted to a pre-set structural analysis software as external loads to calculate the structural deformation of the vehicle during the water exit process. After calculating the structural deformation, the displacement and velocity of the vehicle are fed back to the fluid to update the mesh and boundary of the fluid domain.

3. The simulation method for the dynamics of a ship emerging from the water as described in claim 1, characterized in that, The physical models include multiphase flow models, turbulence models, cavitation models, and ship structure models.

4. The simulation method for the dynamics of a ship emerging from the water as described in claim 3, characterized in that, The cavitation model is obtained using the following formula: in, Evaporation rate For condensation rate, The density of the vapor phase is... The density of the liquid, This represents the volume fraction of steam. Cavitation radius, It is the saturated vapor pressure. Local pressure.

5. The simulation method for the dynamics of a ship emerging from the water as described in claim 1, characterized in that, The governing equations include fluid domain governing equations and structural domain governing equations; The governing equations of the fluid domain include the mixed-phase mass conservation equation, the momentum conservation equation, and the VOF phase fractional transport equation; The governing equations of the structural domain include equilibrium equations.

6. The simulation method for the water-emerging dynamics of a ship as described in claim 5, characterized in that, The mass conservation equation for the mixed phase is obtained using the following formula: ; The momentum conservation equation is obtained using the following formula: ； The fractional transport equation for the VOF phase is obtained using the following formula: ; in, For fluid density, For time, Let i be the component of the velocity vector in the i-direction. Let be the component of the velocity vector in the j-direction. Let i be the spatial coordinates in the direction of i. Let j be the spatial coordinate in the j-direction. For fluid pressure, The dynamic viscosity of the fluid. For turbulent viscosity, This represents the component of the gravitational acceleration vector in the i-direction; The volume fraction of phase q within the control unit, 0 ≤ ≤1, when When =0, the control unit is full of water. When =1, the control unit is filled with air; when 0 < When <1, the control unit is located at the interface between the two phases. Let be the component of the velocity vector in the j-direction. For interphase quality transmission rate, Let q be the density of phase q.

7. The simulation method for the dynamics of a ship emerging from the water as described in claim 5, characterized in that, The equilibrium equation is obtained using the following formula: in, For Cauchy stress tensor, Let be the divergence of the stress tensor. The volume force acting on the ship. For the density of the carrier, Let be the component of the acceleration vector in the i-direction.

8. A simulation system for the dynamics of a ship emerging from the water, characterized in that, The system includes: a model and strategy construction module, a control and solution module, a first definition module, a second definition module, and a simulation module; The model and strategy building module is used to establish the physical model and coupling strategy for the simulation of the water-emerging dynamics of the aircraft body; The control and solver module is used to set the control equations and solver for the simulation of the water-emerging dynamics of the aircraft body; The first definition module is used to perform mesh generation and define the data exchange interface for the fluid domain during the simulation of the dynamics of the vehicle emerging from the water. The second definition module is used to define the boundary conditions, initial conditions, and motion modes for the dynamic simulation of the vehicle emerging from the water; The simulation module is used to perform water exit dynamics simulation of the vehicle based on the physical model, the coupling strategy, the control equations, the solver, the divided mesh, the data exchange interface, the boundary conditions, the initial conditions, and the motion mode.

9. A simulation device for the dynamics of a ship emerging from the water, comprising a memory and a processor, characterized in that, The memory stores a computer program that, when executed by the processor, causes the processor to perform the steps of the method as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it causes the processor to perform the steps of the method as described in any one of claims 1 to 7.

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