Structure icebreaking water entry simulation and response evaluation method based on multi-field coupling model

Abstract

The invention discloses a structure icebreaking water entry simulation and response evaluation method based on a multi-field coupling model. According to the method, an Euler finite element method, an immersion boundary method and a near-field dynamics method are used for solving a fluid, a fluid-solid coupling interface and a structure respectively, stable and effective full space-time simulation of the structure icebreaking water entry process is achieved, and a response evaluation method is established based on a numerical simulation database; combining a plurality of dominant numerical algorithms, and integrating the numerical algorithms; a cavitation effect, a turbulence effect, a multi-physics coupling interface, structural damage and the like are fully considered, and an adaptive algorithm and a message passing interface parallel method are introduced to improve the simulation speed; according to the method, the complex multi-physical field fluid-solid coupling action mechanism of ice breaking and water entering of the whole space-time structure is mastered, and the method is suitable for the load reduction and stability augmentation design of a cross-medium structure for polar region environment operation.

Description

Technical Field

[0001] The present invention relates to a structural evaluation method, and more particularly to a method for simulating and evaluating the response of a structure breaking ice and entering water based on a multi-field coupling model. Background Art

[0002] The process of a structure breaking ice and entering water is a typical application scenario faced by polar equipment during operation. This physical problem is a difficult problem involving multiple disciplines. Scientifically, it involves complex multiphase flow phenomena such as large deformations, cavitation, and turbulence of fluids, as well as complex multi-physical field interface coupling effects, and also involves multi-scale damage phenomena such as ice crack generation and propagation. Engineeringly, due to the presence of ice layers, significant changes will occur in key parameters such as the impact load and motion stability of the structure, which are all blank research fields.

[0003] With the development of computer technology, simulating and calculating physical processes and phenomena in the field of multi-physical field coupling mechanics through numerical simulation methods has become the mainstream research method, and methods such as finite element and peridynamics have been rapidly developed and applied. The problem of a structure breaking ice and entering water involves the coupling of multi-physical fields of water-steam-structure-ice. Solving such an extremely nonlinear problem requires the joint use of multiple advantageous numerical algorithms, and existing foreign commercial software has not integrated a solver that can effectively solve the full-time and full-space evolution of this physical problem.

[0004] There is a lack of relevant technologies to systematically reveal the influence of the presence of ice on the full-time and full-space impact load, stability, and cavitation evolution characteristics, and the mechanism of complex fluid-structure coupling is not clear. Furthermore, due to the lack of clear response evaluation indicators, there are no design standards and load reduction and stability enhancement strategies for trans-medium structures operating in polar environments. Summary of the Invention

[0005] Aiming at the research difficulties related to the full-time and full-space evolution of multi-physical fields in the process of a structure breaking ice and entering water, the present invention proposes a method for simulating and evaluating the response of a structure breaking ice and entering water based on a multi-field coupling model, which has high application value.

[0006] The method for simulating and evaluating the response of a structure breaking ice and entering water based on a multi-field coupling model of the present invention includes the following steps: 1) Establish a three-dimensional multi-field coupling calculation model of the structure, flow field, and ice field; the model includes the shape of the structure, the size of the flow field, and the size of the ice field, and divides different gradient regions of the three-dimensional multi-field coupling calculation model into corresponding fluid domain grids and solid domain particles of different calculation models; 2) Use the Euler finite element method to solve the Euler equation involved in the three-dimensional multi-field coupling calculation model of the flow field to obtain the state of each fluid domain grid in the flow field; during the solution process, use the fluid domain grid generated in step 1), and consider the characteristic parameters and compressibility characteristics of water and air; 3) Combine the joint direct force method and the penalty function method to establish the immersed boundary method through local restrictions on velocity and pressure. Transfer the forces of the structure and the ice field to the fluid domain grid through the combined immersed boundary method, so as to realize the coupling effect at the coupling interfaces of the structure-ice field coupling, the structure-fluid coupling, and the ice field-fluid coupling; 4) Solve the ice field and the structure by the peridynamics method to obtain the states of each solid domain particle of the structure and the ice field; 5) Couple the Euler finite element method, the immersed boundary method, and the peridynamics method in the time marching scheme to obtain the unified time step required for the joint calculation of the three algorithms, and use the unified time step to solve these three algorithms uniformly; 6) For the algorithms obtained in steps 2) - 5), perform simulations using a high-performance computing environment. Introduce the adaptive algorithm and the message passing interface parallel method to improve the simulation speed. Collect relevant data during the entire simulation process to obtain simulation results. The relevant data includes the pressure field, the velocity field, the structural velocity, the ice crack pattern, and the force acting on the structure, i.e., the impact load; 7) Compare the simulation results with the experimental data to verify and confirm the accuracy and reliability of the simulation results, and correct the model and the algorithm; 8) Create a numerical simulation database using the simulation results corresponding to different combinations of initial parameters in step 6) for query and analysis; 9) Propose quantitative indicators for the structural response, evaluate the structural response, so as to optimize the structure, and define specific criteria for evaluating the ice-breaking water-entry response of the structure according to the quantitative indicators.

[0007] Among them, in step 1), the sizes of the flow field and the ice field include the length, width, and height of the flow field and the ice field. The structure and the ice field are solids, and solid domain particles are used in the multi-field coupling three-dimensional calculation model; the flow field is the space occupied by fluid motion, and fluid domain grids are used in the multi-field coupling three-dimensional calculation model. The fluid includes water and air, and the air includes the air above the water and the bubbles in the water.

[0008] Generate the fluid domain grids and solid domain particles of the corresponding different calculation models for different gradient regions of the multi-field coupling three-dimensional calculation model: use finer fluid domain grids and particle resolutions in the high-gradient regions; conversely, use coarser fluid domain grids and particle resolutions in the low-gradient regions.

[0009] In step 2), when solving the Euler equations, turbulent effects and cavitation effects are taken into account, corresponding to implanting a large eddy simulation turbulence model and a Reynolds-averaged cavitation model. The state of the fluid domain grid includes: the density, mass, velocity, acceleration, momentum, and energy of water and air. The core technical means of the Euler finite element method is operator splitting, which divides the solution of the Euler equations into Lagrangian calculation steps and Eulerian calculation steps. Among them, the large eddy simulation turbulence model provides more accurate turbulence simulation in extreme flow problems. This method directly simulates large-scale vortices in turbulence and reduces the computational effort by filtering and modeling small-scale turbulence. The Reynolds-averaged cavitation model simulates cavitation phenomena by tracking the interface between bubbles and the fluid, and takes into account the morphological changes and motions of bubbles to solve the complex cavitation problems brought about by multiple interfaces.

[0010] In step 3), when adopting the combined immersed boundary method, appropriate interpolation shape functions and local constraint conditions need to be selected.

[0011] In step 4), the bond-based peridynamics model is used to model the structure and the ice field. The state of the solid domain particles includes: mass, velocity, acceleration, and damage degree.

[0012] In step 5), each algorithm solution requires a time step, and the smallest one is taken to obtain a unified time step.

[0013] The time step of the fluid is solved by the convergence condition judgment number (i.e., the CFL) condition. The CFL condition is an important parameter related to the stability and convergence of numerical calculations. The CFL condition is named after Courant, Friedrichs, and Lewy.

[0014] In step 6), a computing cluster is composed of multiple high-performance servers with multiple central processing unit cores and a large amount of memory. These nodes run the simulation in parallel, thus significantly shortening the calculation time. The adaptive algorithm dynamically adjusts the strategy according to the characteristics of the problem to improve efficiency; the message passing interface parallel method MPI algorithm uses multi-processor parallel computing to accelerate large-scale calculations. The combination of the two can effectively solve complex problems and improve the calculation speed and accuracy.

[0015] In step 7), based on high-speed photography, data acquisition sensing technology, and particle image velocimetry for fine flow field measurement technology, a structural ice-breaking entry mechanism experiment is carried out to obtain qualitative and quantitative experimental results. Based on sufficient experimental data, the numerical model is verified and optimized.

[0016] The experimental device includes: a light source, an image acquisition device, a transparent water tank, a mirror, and a discharge device; wherein, water is contained in the water tank, and ice is placed on the water surface; the discharge device is connected to the inside of the water tank through two wires, there is a distance between the ends of the two wires, and the discharge device energizes the two wires so that high-pressure bubbles are generated at the ends of the wires; the light source is located above the water tank and emits illumination light to irradiate into the water tank; the image acquisition device collects images of the process of the structure breaking through the ice and entering the water through the mirror. The ice floating on the water is fixed in position by a fixing wire, one end of the fixing wire is fixed on the side wall of the water tank, and the other end is fixed on the ice.

[0017] The correction of the model and algorithm includes: the correction of the multi-field coupling three-dimensional calculation model and the division of the fluid domain grid and solid domain particles in step 1), the interpolation shape function and local constraint conditions adopted by the immersed boundary method in step 3), and the unified time step in step 5).

[0018] In step 8), the initial parameters include the shape of the structure, the moving speed and angle of the structure, and the characteristic parameters of the ice field; the typical working conditions under different initial parameters such as the shape of different structures, the moving speed and angle of different structures, and the characteristic parameters of different ice fields are studied, the corresponding impact loads and stabilities are analyzed, and a numerical simulation database suitable for the actual engineering requirements is established based on this. The characteristic parameters of the ice field are the length, width, and height of the ice field.

[0019] In step 9), the quantitative indicators of the structural response include calculating the peak value of the impact load, the pulse width of the impact load, and the velocity decay index; the response of the structure under the impact load is mainly evaluated, the data of the quantitative indicators are extracted from the simulation results, the comprehensive evaluation score is calculated, and the optimal structural design is obtained based on the comprehensive evaluation score.

[0020] Advantages of the present invention: The present invention uses the Euler finite element method, the immersed boundary method, and the peridynamic method to solve the fluid, the fluid-structure coupling interface, and the structure respectively, realizes the stable and effective full-time and space simulation of the process of the structure breaking through the ice and entering the water, and establishes a response evaluation method based on the numerical simulation database; combines three dominant numerical algorithms of the Euler finite element method, the immersed boundary method, and the peridynamic method, and develops a solver for efficiently and stably solving the full-time and space evolution of this physical problem through numerical algorithm integration; fully considers the cavitation effect, the turbulence effect, the multi-physical field coupling interface, and the structural response, etc., and introduces the adaptive algorithm and the message passing interface parallel method to improve the simulation speed; the present invention masters the complex multi-physical field fluid-structure coupling action mechanisms such as the multi-stage impact load and the structural failure effect in the full-time and space structure breaking through the ice and entering the water, and provides a reference for the design of load reduction and stability enhancement of the trans-medium structure for polar environment operations. Description of the Drawings

[0021] Figure 1Flowchart of the structural ice-breaking and water-entry simulation and response evaluation method based on the multi-field coupling model of the present invention; Figure 2 Typical structural ice-breaking and water-entry result diagram simulated by the structural ice-breaking and water-entry simulation and response evaluation method based on the multi-field coupling model of the present invention; Figure 3 Schematic diagram of the experimental device of an embodiment of the structural ice-breaking and water-entry simulation and response evaluation method based on the multi-field coupling model of the present invention; Figure 4 Experimental and numerical simulation comparison diagram of an embodiment of the structural ice-breaking and water-entry simulation and response evaluation method based on the multi-field coupling model of the present invention; Figure 5 Experimental and numerical simulation quantitative comparison diagram of an embodiment of the structural ice-breaking and water-entry simulation and response evaluation method based on the multi-field coupling model of the present invention; Figure 6 Schematic diagram of a typical evaluation method of an embodiment of the structural ice-breaking and water-entry simulation and response evaluation method based on the multi-field coupling model of the present invention. Detailed implementation manners

[0022] The present invention will be further described below with reference to the accompanying drawings through specific embodiments.

[0023] The structural ice-breaking and water-entry simulation and response evaluation method based on the multi-field coupling model in this embodiment, as Figure 1 shown, includes the following steps: 1) Use the Abaqus / CAE module to create three-dimensional calculation models of the structure, flow field, and ice field; the three-dimensional calculation models include the shape of the structure, the size of the flow field, and the size of the ice field, and divide the different gradient regions of the three-dimensional calculation models into the fluid domain grids and solid domain particles of the corresponding different calculation models; The structural geometry is input according to the actual situation, and the built-in geometric modeling tool of Abaqus or the CAD model is imported; among them, the flow field area needs to be defined according to the structure and ice layer geometry to ensure full coverage of the calculation area; use the Abaqus / CAE module for mesh division; considering the high-gradient regions such as the interfaces between the structure and the flow field, and the flow field and the ice layer, finer meshes need to be used in these regions; use structured or hybrid meshes, and use smaller mesh sizes in the high-gradient regions; the mesh quality needs to be strictly checked to ensure good mesh shapes and avoid the appearance of distorted meshes; 2) Use the Euler finite element method to solve the Euler equations involved in the three-dimensional calculation model of the flow field to obtain the state of each fluid domain grid in the flow field. The state of the fluid domain grid includes: the density, mass, velocity, acceleration, momentum, and energy of water and air; during the solution process, use the fluid domain grids generated in step 1), and consider the characteristic parameters and compressibility characteristics of water and air; In solving the Euler equations, a large eddy simulation turbulence model is implanted to account for the turbulence effect, and a cavitation model based on Reynolds averaging is implanted to account for the cavitation effect; the core technical means of the Euler finite element method is operator splitting, which divides the solution of the Euler equations into Lagrangian calculation steps and Eulerian calculation steps; during the calculation of the Eulerian calculation step, the calculation results of the Lagrangian step are first loaded, and then the transport process of the Eulerian calculation step is carried out. The transport volume is obtained by determining the fluid motion direction, and physical quantities such as momentum, density, and energy are updated based on the solution of the transport volume; after the transport of the Eulerian calculation step is completed, the new pressure is obtained from the new density and the Lagrangian step calculation of the next time step is restarted, and so on, continuously cycling, and finally the solution of the fluid motion process over the entire time period is realized; 3) Combine the combined direct force method and the penalty function method to establish an immersed boundary method through local constraints on velocity and pressure, and transfer the forces of the structure and the ice field to the fluid domain grid through the combined immersed boundary method, so as to realize the coupling effects at the interfaces of structure-ice field coupling, structure-fluid coupling, and ice field-fluid coupling; When using the direct force method to deal with the fluid-structure interaction problem, there is no use of the stiffness coefficient, so this algorithm can avoid certain numerical oscillations when dealing with strong transient problems, but the corresponding calculation efficiency is insufficient; for the penalty function immersed boundary method, it is a numerical method commonly used in current commercial software, with relatively higher calculation efficiency and stability, but the introduction of the stiffness coefficient will lead to some numerical drawbacks; the present invention combines the combined direct force method and the penalty function method to establish a combined immersed boundary method through local constraints on velocity and pressure, that is, the direct force method is adopted when the relative velocity between the fluid grid and the solid boundary node is large or the fluid grid pressure is high, and the penalty function immersed boundary method is adopted in other cases, so as to establish a relatively high-precision, stable and efficient fluid-structure interaction algorithm, where the discriminant condition can be appropriately adjusted according to specific problems, and the formula expression is as follows; Among them, is the fluid-structure interaction interface force, is the interface force calculated by the penalty function, is the interface force calculated by the direct force method, v is the relative motion velocity of the fluid and the solid, P is the pressure, μ is the limiting function; 4) Solve the ice field and the structure by the peridynamics method to obtain the states of each solid domain particle of the structure and the ice field; The non-local meshless idea of the peridynamics method is its typical feature. When solving the model, the entire solid computational domain is discretized into many material points, and physical parameters such as the density, velocity, force, and mass of these material points exist. Based on this, the integral form of the basic equation is discretized and solved through non-local processing means. 5) Couple the Euler finite element method, the immersed boundary method, and the peridynamics method in the time marching scheme to obtain the unified time step required for the joint calculation of the three algorithms, and use the unified time step to solve these three algorithms uniformly. To ensure numerical stability, the time step is obtained through the following formula, corresponding to the fluid stable time step and the structure stable time step respectively: where, min represents taking the minimum value, t is time, L e is the grid length, c is the grid sound speed, u is the grid velocity, ρ is the density, N is the number of particles, H j is the discrete domain volume parameter of the j-th grid, f is the constitutive force, and η is the state; 6) For the algorithms obtained in steps 2) - 5), use a high-performance computing environment to perform the simulation, introduce the adaptive algorithm and the message passing interface parallel technology to improve the simulation speed, and collect relevant data during the entire simulation process, including the pressure field, velocity field, structural velocity, ice crack pattern, and the force acting on the structure, i.e., the impact load; Submit the operation for the target working condition, and it is necessary to specify the required number of central processing unit cores, memory size, and other resource requirements; during the output process of the algorithm results, embed a data collection module; this module regularly writes key data into files during the simulation process, and these data include: recording the pressure and velocity values of each node or grid within the computational domain; the output frequency needs to be weighed according to the simulation accuracy and storage space; recording the displacement and stress of the structural nodes for analyzing the structural velocity and stress distribution; recording information such as the starting position, propagation direction, and length of the crack; recording the resultant force acting on the structure and its distribution; obtaining the simulation results; After the simulation is completed, transfer the simulation results from the high-performance computing cluster to the local machine; use the appropriate visualization tool Tecplot to perform visual analysis on the result data, visually display the pressure field, velocity field, structural velocity, and ice crack pattern, and perform quantitative analysis on the results; it is necessary to write custom scripts for data processing and analysis; typical numerical simulation results are as Figure 2 shown, Figure 2 the left figure in the middle is the side view, and the right figure is the three-dimensional view; 7) Verify and confirm the accuracy and reliability of the simulation results by comparing the simulation results with the experimental data, and correct the model and algorithm; The experimental device includes: a light source, an image acquisition device, a transparent water tank, a mirror, and a discharge device; among them, water is filled in the water tank, and ice is placed on the water surface; the discharge device is connected to the inside of the water tank through two wires, and there is a distance between the ends of the two wires. The discharge device energizes the two wires so that high-pressure bubbles are generated at the ends of the wires; the light source is located above the water tank and emits illumination light into the water tank; the image acquisition device collects images of the ice-breaking and water-entry process of the structure through the mirror; the ice floating on the water is fixed in position by a fixing wire. One end of the fixing wire is fixed on the side wall of the water tank, and the other end is fixed on the ice, as Figure 3 shown; in the comparative verification example, the length and width of the ice are both 10 cm, the thickness is 0.5 cm, the initial distance of the bubble from the lower surface of the ice is 1.5 cm, and the maximum radius of the bubble is 1.5 cm; among them, the initial distance and the ice layer thickness are both dimensionless processed by the maximum radius of the bubble, that is, the initial distance parameter is 1.00 and the thickness parameter is 0.33; Figure 4 is the top view of the typical physical process in the experiment (left figure) and numerical simulation (right figure), Figure 4 The left and right figures in Figure 5 show the typical physical characteristics of the ice crack state by comparison. The numerical simulation results are in good agreement with the experiment, For the quantitative verification effect, the effectiveness of the algorithm is verified; 8) Create a database using the simulation results corresponding to the different initial parameters in step 6) for effective query and analysis: The initial parameters include the shape of the structure, the movement speed and angle of the structure, and the characteristic parameters of the ice field; import the simulation result files generated in step 6) into the database, study the typical working conditions under different initial parameters such as the shape of different structures, the movement speed and angle of different structures, and the characteristic parameters of different ice fields, analyze the corresponding impact loads and stabilities, and based on this, establish a numerical simulation database suitable for the actual engineering requirements; it needs to be implemented using the import tool provided by the database or a programming language combined with a database connection library; the script needs to process simulation result files in different formats and convert them into a format acceptable to the database; the data import process should include a data verification and error handling mechanism to ensure the integrity and accuracy of the data; use the query language provided by the database for data query and analysis; write complex query statements using the query language to extract the required data, and perform statistical analysis and data visualization; use the functions and aggregation operations provided by the database to simplify data processing; use the database connection library to write programs in a programming language to access and process the data in the database; 9) Propose quantitative indicators for structural response, evaluate the structural response, and thus optimize the structure. Define specific criteria for evaluating the ice-breaking water-entry response of the structure according to the quantitative indicators: Preprocess the data of the simulation results, including cleaning the data, removing outliers and noise, and ensuring the consistency of data units; according to the data format of the simulation results, scripts need to be written for data conversion and formatting for subsequent analysis; Analyze the impact load on the structure and calculate its peak value; achieve this by finding the maximum value of the force or pressure curve in the simulation data; the calculation area and direction of the impact load need to be clearly defined; if the impact load is distributed on the surface of the structure, the overall load or local maximum load needs to be considered; determine the action time of the impact load, that is, the pulse width of the impact load; calculate it by measuring the time length when the load curve exceeds a certain threshold (2 times the acceleration of gravity); analyze the velocity change of the structure during the ice-breaking water-entry process and calculate the velocity decay rate; achieve this by calculating the change rate of the structure velocity over time; the velocity decay reflects the energy absorption capacity and impact damping characteristics of the structure; Based on the above calculation results, define specific evaluation criteria, combine multiple indicators such as the peak value of the impact load, the pulse width of the impact load, and the velocity decay rate, and construct a multi-dimensional evaluation system; use the weighted average method or other methods to comprehensively consider multiple indicators, and finally obtain a comprehensive evaluation score. The calculation formula is shown as follows: Among them, K is the comprehensive evaluation score, F max is the peak value of the impact load, F width is the pulse width of the impact load, v attention is the velocity decay rate, σ is the weighting function; change the shape of the structure, and obtain the corresponding comprehensive evaluation scores for different structural shapes. The higher the comprehensive evaluation score, the more reliable the structural design; according to the actual engineering requirements, adjust the quantitative weights of each indicator. Typical evaluation methods are as Figure 6 shown.

[0024] Finally, it should be noted that the purpose of publishing the embodiments is to help further understand the present invention. However, those skilled in the art can understand that various substitutions and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the present invention should not be limited to the content disclosed in the embodiments, and the scope claimed by the present invention is defined by the scope of the claims.

Claims

1. A method for simulating the ice-breaking entry of a structure and evaluating its response based on a multi-field coupling model, characterized in that, The structural ice-breaking water-entry simulation and response evaluation method includes the following steps: 1) Establish a multi-field coupled three-dimensional calculation model of the structure, flow field, and ice field; and divide different gradient regions into corresponding different fluid domain grids and solid domain particles; 2) Use the Euler finite element method to solve the Euler equations involved in the multi-field coupled three-dimensional calculation model of the flow field to obtain the state of each fluid domain grid in the flow field; use the fluid domain grid generated in step 1) during the solution process; 3) Combine the combined direct force method and the penalty function method to establish the immersed boundary method through local restrictions on velocity and pressure, and transfer the forces of the structure and ice field to the fluid domain grid through the combined immersed boundary method, so as to realize the coupling effect at the coupling interfaces of the structure and ice field, structure and fluid, and ice field and fluid; 4) Solve the ice field and structure by the peridynamics method to obtain the state of each solid domain particle of the structure and ice field; 5) Couple the Euler finite element method, the immersed boundary method, and the peridynamics method in the time marching scheme to obtain the unified time step required for the three algorithms to calculate together, and use the unified time step to solve these three algorithms uniformly; 6) Execute the simulation on the algorithms obtained in steps 2) to 5), introduce the adaptive algorithm and the message passing interface parallel method to improve the simulation speed, and collect data during the whole simulation process to obtain the simulation results; 7) Compare the simulation results with the experimental data, and correct the model and algorithm; 8) Create a numerical simulation database using the simulation results corresponding to different combinations of initial parameters in step 6); 9) Propose a quantitative index for the structural response, evaluate the structural response, so as to optimize the structure, and define specific criteria for evaluating the ice-breaking water-entry response of the structure according to the quantitative index.

2. The method for simulating the ice-breaking entry of a structure and evaluating its response according to claim 1, characterized in that, In step 1), the model includes the shape of the structure, the size of the flow field, and the size of the ice field; the size of the flow field and the ice field includes the length, width, and height of the flow field and the ice field.

3. The method for simulating the ice-breaking entry of a structure and evaluating its response according to claim 1, characterized in that, In step 2), the turbulent effect and cavitation effect are taken into account when solving the Euler equations, and the large eddy simulation turbulence model and the Reynolds-averaged cavitation model are implanted correspondingly.

4. The method for simulating the ice-breaking entry of a structure and evaluating its response according to claim 1, characterized in that, In step 3), when using the combined immersed boundary method, set the interpolation shape function and local restriction conditions.

5. The method for simulating the ice-breaking entry of a structure and evaluating its response according to claim 1, characterized in that, In step 4), use the bond-based peridynamics model to model the structure and ice field.

6. The method for simulating the ice-breaking entry of a structure and evaluating its response according to claim 1, characterized in that, In step 5), set a time step for each algorithm solution, and take the smallest time step as the unified time step.

7. The method for simulating the ice-breaking entry of a structure and evaluating its response according to claim 1, characterized in that, In step 7), the experimental device includes: a light source, an image acquisition device, a transparent water tank, a mirror, and a discharge device; among them, water is filled in the water tank, and ice is placed on the water surface; the discharge device is connected to the inside of the water tank through two wires, there is a distance between the ends of the two wires, and the discharge device energizes the two wires so that high-pressure bubbles are generated at the ends of the wires; the light source is located on the water tank and emits illumination light to irradiate the inside of the water tank; the image acquisition device collects images of the process of the structure breaking into the water through the mirror.

8. The method for simulating the ice-breaking entry of a structure and evaluating its response according to claim 1, characterized in that, In step 7), the correction of the model and algorithm includes: the correction of the multi-field coupling three-dimensional calculation model in step 1), the division of the fluid domain grid and the solid domain particles, the interpolation shape function and local constraint conditions adopted by the immersed boundary method in step 3), and the unified time step in step 5).

9. The method for simulating the ice-breaking entry of a structure and evaluating its response according to claim 1, characterized in that, In step 8), the initial parameters include the shape of the structure, the velocity of the structure, and the characteristic parameters of the ice field; a numerical simulation database is established under the initial parameters of different structural shapes, different structural velocities, and different ice layer characteristic parameters.

10. The method for simulating the ice-breaking entry of a structure and evaluating its response according to claim 1, characterized in that, In step 9), the quantitative indicators of the structural response include the calculated peak impact load, the pulse width of the impact load, and the velocity decay index; the response of the structure under the impact load is evaluated, the data of the quantitative indicators are extracted from the simulation results, the comprehensive evaluation score is calculated, and the optimal structural design is obtained based on the comprehensive evaluation score.

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