Method and system for simulating high-speed penetration icebreaking water entry of projectile

Abstract

The invention discloses a projectile high-speed penetration icebreaking water entry simulation method and system. The method mainly comprises the steps that a projectile high-speed water entry calculation model is established based on an Euler-Lagrange coupling method; an ice layer failure fracture model is established according to the failure damage form of the ice layer under the high strain rate; according to the constitutive relation of the metal structure material, a Johnson-Cook constitutive equation and a damage model are adopted to reflect the strain performance of the metal material; the interaction between the projectile and the fluid and the interaction between the ice layer and the fluid are defined through universal contact, and the contact behavior between the projectile and the ice layer is defined through surface-surface contact; a penalty function method is adopted to process the strong coupling process in the high-speed collision of the projectile and the ice layer; based on a projectile high-speed water entry calculation model, an ice layer failure fracture model, the strain performance of a metal material, the interaction between the projectile and fluid, the interaction between the ice layer and the fluid, the contact behavior between the projectile and the ice layer and the strong coupling process, numerical simulation is conducted on projectile penetration icebreaking water entry, and cavitation evolution and trajectory characteristic information is obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of polar ice zone hydrodynamic analysis, and in particular to a method and system for simulating high-speed penetration of a projectile into ice and water. Background Art

[0002] Developed based on the advantages of air-to-sea combat, cross-media projectiles are a powerful deterrent and strike tool. The cavitation bubbles created by the instantaneous flow separation upon water entry significantly reduce navigational resistance and enhance the projectile's ability to maintain underwater velocity. The Arctic region is a long-frozen treasure trove, housing at least 13% of the world's proven oil reserves. With global warming, Arctic development is becoming increasingly accessible. Global players, especially those in northern Europe, are aware of its enormous potential economic benefits and commercial value. Arctic development has become a necessity, profoundly impacting the global economic and geopolitical landscape. Therefore, the development of cross-media weapons and equipment suitable for operations in low-temperature, icy waters is urgently needed. Cross-media projectiles operating in icy waters must first penetrate the ice. This process, accompanied by stress concentration, inevitably negatively impacts the projectile's structural strength and the dynamic evolution of the cavitation bubble upon breaking through the ice and entering the water. This, in turn, disrupts the projectile's hydrodynamic loads and kinematic stability, thereby weakening the cross-media projectile's combat effectiveness. Summary of the Invention

[0003] The present invention aims to address the shortcomings and deficiencies in numerical simulation technology for the high-speed water entry process of a projectile interacting with ice in a polar ice environment. A method for simulating the high-speed penetration of a projectile into water through ice is proposed. The method specifically comprises the following steps:

[0004] A computational model for high-speed projectile entry into water was established based on the Euler-Lagrangian coupling method.

[0005] An ice failure fracture model is established based on the failure damage form of ice under high strain rate;

[0006] According to the constitutive relationship of metal structural materials, the Johnson-Cook constitutive equation and damage model are used to reflect the strain properties of metal materials;

[0007] The interaction between projectile and fluid, ice layer and fluid is defined by general contact, and the contact behavior between projectile and ice layer is defined by surface-to-surface contact.

[0008] The penalty function method is used to deal with the strong coupling process in the high-speed collision between the projectile and the ice layer.

[0009] Based on the calculation model of high-speed projectile entry into water, the ice failure and fracture model, the strain properties of metal materials, the interaction between projectile and fluid, ice and fluid, the contact behavior between projectile and ice, and the strong coupling process, a numerical simulation of projectile penetration through ice and entry into water is carried out to obtain information on cavitation evolution and ballistic characteristics.

[0010] Preferably, a calculation model for high-speed water entry of a projectile is established based on the Euler-Lagrange coupling method, including:

[0011] Based on the first property of Euler algorithm, the continuity equation, momentum conservation equation and energy conservation equation are obtained;

[0012] Based on the second property of Lagrangian algorithm, the governing equation is obtained;

[0013] Based on the continuity equation, momentum conservation equation, energy conservation equation, and control equation, the central difference algorithm is used to solve the dynamic equations to obtain acceleration and velocity representations;

[0014] Based on the acceleration and velocity representation, the motion equation, water state, and air state of the projectile entering the water at high speed are obtained as the calculation model for the projectile entering the water at high speed.

[0015] Preferably, the first property includes: the Euler algorithm allows materials to flow through unit boundaries in a rigid grid, and different substances can exist in the rigid grid; the second property includes: the Lagrangian algorithm performs numerical solution through discretization, and the deformation of the material and the grid node corresponds one to one and remains consistent.

[0016] Preferably, the speed is expressed as

[0017] Acceleration is expressed as S represents the displacement, its subscript represents the corresponding moment, and Δt is the time step;

[0018] The equation of motion is:

[0019] Ma t +Cv t +KS t =Q t

[0020]

[0021] Where M is the mass matrix, C is the damping matrix, K is the stiffness matrix, Q t is the load vector;

[0022] The state of water is defined by the linear Us-Up state equation, and the motion of water is simulated by the NS equation;

[0023] The state of air adopts the ideal gas state equation.

[0024] Preferably, an ice layer failure fracture model is established for the failure damage form of ice layers under high strain rates, including:

[0025] At the beginning of the collision, the ice material first experiences an elastic stage, and the stress-strain relationship satisfies Hooke's law;

[0026] The projectile-ice collision is a transient dynamic process. The ice layer continues to be compressed and instantly enters the plastic stage. Here, the Tsai-Wu criterion is used as the yield criterion for the ice material:

[0027] The damage and cracks in the sea ice during the collision process are reflected through the accumulation of plastic deformation. When the damage accumulates to a critical value, the sea ice no longer has the bearing capacity and fails. At this time, the empirical failure criterion is adopted.

[0028] The yield criterion and the empirical failure criterion constitute the ice layer failure fracture model.

[0029] Preferably, the empirical failure criterion is:

[0030]

[0031] p<p c

[0032]

[0033] in, is the equivalent plastic strain, ε f is the failure strain, ε0 is the initial failure strain; ε0 is the initial failure strain, p is the hydrostatic pressure, p c For the cut-off pressure.

[0034] When sea ice is under compressive stress, When , the ice unit fails;

[0035] Sea ice is in a tensile stress state when p<p c The ice unit fails.

[0036] Preferably, based on the constitutive relationship of the metal structural material, the Johnson-Cook constitutive equation and the damage model are used to reflect the strain properties of the metal material, including:

[0037]

[0038] Wherein, σ is the equivalent stress; A, B, C, n, and m are the relevant parameters of the material, A is the quasi-static yield stress, B is the strain hardening constant, C is the strain rate hardening coefficient, m is the temperature correlation coefficient, and n is the strain hardening exponent; ε is the equivalent plastic strain; T is the instantaneous absolute temperature of the material; T m is the melting temperature; T t is the conversion temperature.

[0039] Preferably, a penalty function method is used to process the strong coupling process in the high-speed collision between the projectile and the ice layer, including:

[0040] f n =kn g n

[0041] f t =-sgn(g t )μ d (k n g n )

[0042] Among them, f n and f t represent normal force and tangential force respectively; g n and g t represent the normal and tangential penetration distances respectively; k n represents the normal penalty stiffness; μ d is the friction factor.

[0043] Preferably, the cavitation evolution and ballistic characteristics information includes: cavitation evolution and ballistic characteristics information, including ice layer fragmentation, crack propagation, ice fragment splashing, cavitation morphology evolution under the interaction with the ice layer and ice fragments during entry into water, velocity flow field, pressure flow field information and projectile structure response characteristics.

[0044] In addition, a second aspect of the present invention further provides a system for simulating high-speed penetration of a projectile into ice and water, comprising:

[0045] Water entry model module: establishes a high-speed water entry calculation model for projectiles based on the Euler-Lagrange coupling method;

[0046] Failure and fracture module: establishes an ice failure and fracture model based on the failure damage form of ice under high strain rate;

[0047] Strain module: Based on the constitutive relationship of metal structural materials, the Johnson-Cook constitutive equation and damage model are used to reflect the strain properties of metal materials;

[0048] Contact module: uses general contact to define the interaction between projectile and fluid, ice layer and fluid, and uses surface-to-surface contact to define the contact behavior between projectile and ice layer;

[0049] Coupling module: uses penalty function method to deal with the strong coupling process in the high-speed collision between projectile and ice layer;

[0050] Simulation Module: Based on the calculation model of high-speed projectile entry into water, ice failure and fracture model, strain properties of metal materials, interaction between projectile and fluid, ice and fluid, contact behavior between projectile and ice, and strong coupling process, the module numerically simulates the projectile penetrating ice and entering water to obtain information on cavitation evolution and ballistic characteristics.

[0051] Beneficial effects:

[0052] The present invention can reveal the evolution of cavitation morphology, velocity flow field, pressure flow field information, projectile structure response characteristics and ballistic characteristics under the interaction with ice layer and ice fragments during ice layer fragmentation, crack expansion, ice fragment splashing and water entry. It helps to deeply explore the flow field characteristics and load action mechanism during the high-speed water entry process of the projectile interacting with the ice layer, and provide a direct reference for the development of new cross-media projectile weapons suitable for ice areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0054] Figure 1 The present invention is a flow chart of a method for simulating high-speed penetration of a projectile through ice and water.

[0055] Figure 2 This is a verification diagram of the cavitation morphology evolution comparing this computational model with related experiments.

[0056] Figure 3 This is a verification diagram of sea ice breakup and crack propagation comparing this computational model with relevant experiments.

[0057] Figure 4 It is a diagram simulating the ice failure, damage and crack propagation process when a projectile penetrates the ice at high speed and enters the water.

[0058] Figure 5 This is a comparison chart of the projectile structure response characteristics when simulating a projectile entering water at high speed in an ice-free environment and an ice-covered environment.

[0059] Figure 6 This is a diagram simulating the evolution of cavitation morphology during the process of a projectile penetrating ice and entering water at high speed.

[0060] Figure 7 It is a diagram simulating the change of velocity flow field during the process of a projectile penetrating through ice and entering water at high speed.

[0061] Figure 8 This is a diagram simulating the changes in the pressure flow field during the process of a projectile penetrating through ice and entering the water at high speed. DETAILED DESCRIPTION

[0062] In order to make the technical solutions and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention:

[0063] like Figure 1A method for simulating high-speed penetration of a projectile through ice and water is shown, and the specific implementation process of the method includes the following steps:

[0064] Step 1: Establish a high-speed water entry calculation model for a projectile based on the Euler-Lagrange coupling method;

[0065] Step 2: Establish an ice failure fracture model based on the failure damage form of the ice layer under high strain rate;

[0066] Step 3: Based on the constitutive relationship of metal structural materials, the Johnson-Cook constitutive equation and damage model are used to reflect the strain properties of metal materials;

[0067] Step 4: Use general contact to define the interaction between the projectile and the fluid, and between the ice layer and the fluid, and use surface-to-surface contact to define the contact behavior between the projectile and the ice layer;

[0068] Step 5: Use the penalty function method to deal with the strong coupling process in the high-speed collision between the projectile and the ice layer;

[0069] Step 6: Based on the calculation model of high-speed projectile entry into water, the ice failure and fracture model, the strain properties of metal materials, the interaction between projectile and fluid, the ice layer and fluid, the contact behavior between projectile and ice layer, and the strong coupling process, a numerical simulation of the projectile penetrating ice and entering water is performed to obtain cavitation evolution and ballistic characteristics information.

[0070] It should be noted that the order of steps 1 to 5 is not limited to a single order, and in other embodiments, they can be arranged in any order.

[0071] like Figure 2 As shown in the figure, a computational model of high-speed projectile entering water is established based on the Euler-Lagrange coupling method for the process of flow separation in the interaction between projectile and fluid. Specifically: Figure 2 The cavitation size of the experimental and numerical simulation results at different depths with a projectile diameter of D is shown (based on the projectile diameter). The following steps can be used to establish a computational model for high-speed projectile entry into water:

[0072] S1.1, the Euler algorithm allows materials to flow across cell boundaries in a rigid grid. Different materials can exist in the Euler grid. Its continuity equation, momentum conservation equation, and energy conservation equation are:

[0073]

[0074] where ρ, U, σ, e, and f represent the density, velocity, specific internal energy, stress, and mass force of the fluid medium, respectively.

[0075] S1.2, the Lagrangian algorithm performs numerical solutions through discretization, and the deformation of the material and the grid nodes correspond one to one and remain consistent. Its governing equation is:

[0076]

[0077]

[0078] where ρ', U', σ', and e' are the density, velocity, stress, and specific internal energy of the Lagrangian medium, respectively.

[0079] S1.3, based on the equations in S1.1 and S1.2, when the central difference algorithm is used to solve the dynamic equations, the acceleration and velocity are expressed as follows:

[0080]

[0081] where v t and a t are the velocity and acceleration at time t, S represents the displacement, and Δt is the time step.

[0082] S1.4. Based on the velocity and acceleration obtained in S1.3, the equation of motion for the projectile entering the water at high speed is:

[0083] Ma t +Cv t +KS t =Q t

[0084]

[0085] Where M is the mass matrix, C is the damping matrix, K is the stiffness matrix, Q t is the load vector.

[0086] S1.5, uses the linear Us-Up state equation to define water, and accurately simulates the movement of water through the NS equation. The state equation of water is:

[0087]

[0088] where Γ0 is the material constant and η represents the nominal volume compressive strain.

[0089] η can be decomposed into:

[0090] η=1-ρ0 / ρ.

[0091] S1.6, the ideal gas state equation for air is:

[0092] P=(γ-1)ρE m -P a

[0093] Where γ is the adiabatic index, E m is the internal energy per unit mass; Pa Indicates the external atmospheric pressure.

[0094] The computational model for high-speed projectile entry into water focuses primarily on the interaction between the projectile and the fluid, as well as the simulation of flow separation. This model, using precise mathematical equations and physical principles, details the complex dynamic interactions between a projectile and the surrounding fluid medium during high-speed water entry. It not only accounts for the pressure waves and fluid dynamics generated by the projectile's motion through water, but also incorporates flow separation caused by factors such as the projectile's shape, velocity, and the physical properties of water. This model enables researchers to better understand the physical mechanisms of projectile motion underwater, enabling them to optimize their designs and improve their performance and accuracy.

[0095] The study of high-speed icebreaking and water entry is a cutting-edge topic in the field of hydrodynamics, but it is not easy to implement in terms of experiments and simulations. Specifically, in terms of experiments: the cross-medium experimental conditions in the low-temperature environment of the ice zone are very harsh, and the equipment is relatively complex. In terms of simulation: the numerical simulation method of ice layer failure and fracture is difficult to implement. In addition, the numerical calculation model of ice layer crack expansion needs to take into account many complex physical factors, including the constitutive relationship of ice, boundary conditions, etc. The complexity of these factors makes the numerical simulation of icebreaking very challenging. In a preferred embodiment of the present invention, Figure 3 and Figure 4 As shown in the figure, an ice failure fracture model is established according to the failure damage form of sea ice under high strain rate to simulate the failure damage and crack propagation of ice under the impact of projectiles.

[0096] When the mechanical loading speed on ice is greater than 0.1 m / s, the strain rate of ice exceeds 10 -3 s -1 , showing brittle characteristics.

[0097] First, at the beginning of the collision, the ice material first experiences an elastic stage, and the stress-strain relationship satisfies Hooke's law:

[0098] σ ij =λδ ij e+2με ij

[0099] Among them, σ ij is the stress tensor, λ and μ are the Lame constants, δ ij is the Kronecker symbol, e is the volume strain, ε ij is the strain tensor.

[0100] Then, since the projectile-ice collision is a transient dynamic process, the ice layer continues to be compressed and instantly enters the plastic stage. The Tsai-Wu criterion is used as the yield criterion for ice materials:

[0101] f(p,J2)=J2-(a0+a1p+a2p 2 )=0

[0102] Where p is the hydrostatic pressure, is the second deviatoric stress invariant, and a0, a1, and a2 are constants.

[0103] Finally, the damage and cracks in the sea ice during the collision process are manifested through the accumulation of plastic deformation. When the damage accumulates to a critical value, the sea ice no longer has the bearing capacity and fails. The empirical failure criteria are as follows:

[0104]

[0105] p<p c

[0106]

[0107] in, is the equivalent plastic strain, ε f is the failure strain, ε0 is the initial failure strain, ε0 is the initial failure strain, p is the hydrostatic pressure, p c is the cut-off pressure. When sea ice is in a compressive stress state, When p<p c The ice unit fails.

[0108] The above ideal elastic-plastic model ("impact initialization" and "Tsai-Wu criterion") and the failure failure criterion constitute the failure fracture model. The research focus of the ice failure fracture model is to deeply explore and analyze the failure behavior and mechanism of ice when impacted by projectiles.

[0109] In the aforementioned embodiment, by analyzing the macroscopic mechanical interactions among the projectile, the ice layer, and the fluid, the fracture pattern of the ice layer, the crack propagation path, and the load-over-time curve can be accurately depicted, thereby effectively simulating the process of the projectile penetrating the ice layer at high speed and entering the water.

[0110] like Figure 5 As shown in the figure, the Johnson-Cook constitutive equation and damage model are used to reflect the strain properties of metal materials based on the constitutive relationship of metal structural materials, thereby reflecting the stress, strain and structural response of the projectile during high-speed penetration, breaking through ice and entering water. The main expression of the constitutive relationship is:

[0111]

[0112] Wherein, σ is the equivalent stress; A, B, C, n, and m are the relevant parameters of the material, A is the quasi-static yield stress, B is the strain hardening constant, C is the strain rate hardening coefficient, m is the temperature correlation coefficient, and n is the strain hardening exponent; ε is the equivalent plastic strain; T is the instantaneous absolute temperature of the material; T m is the melting temperature; T t is the conversion temperature.

[0113] like Figure 6-Figure 8 As shown in Figure 2, the strong coupling process in the high-speed collision between the projectile and the ice layer is handled by defining a general contact and penalty function method, which is specifically expressed as follows:

[0114] General contact is used to define the contact behavior between the Eulerian material surface and the Lagrangian structure surface;

[0115] Surface-to-surface contact is used to define the contact behavior between the projectile and the ice layer;

[0116] The penalty function method and finite sliding approach are used to simulate the tangential and normal behaviors during the strong coupling process of high-speed collision between the projectile and the ice layer, thereby dealing with the strong nonlinear problem of large deformation in the calculation process.

[0117] The penalty function method adds a penalty term directly related to the contact constraint to the objective function. When a node penetrates the contact surface, the penalty term increases the value of the objective function, thereby forcing the node to move on the contact surface and adjust the node position to avoid further penetration. The basic equation satisfied is as follows:

[0118] f n =k n g n

[0119] f t =-sgn(g t )μ d (k n g n )

[0120] Among them, f n and f t represent normal force and tangential force respectively; g n and g t represent the normal and tangential penetration distances respectively; k n represents the normal penalty stiffness; μ d is the friction factor.

[0121] In a preferred embodiment, a method for simulating high-speed projectile penetration through ice and water is established. Initial conditions are set based on a specific simulation environment, including the computational domain size, water and air medium states (e.g., density and viscosity), projectile and ice material (e.g., density, Young's modulus, Poisson's ratio), projectile velocity, Eulerian domain and Lagrangian cell meshing, and time step. Numerical simulations are then performed on the high-speed projectile impact with ice and water, obtaining information on flow field characteristics.

[0122] like Figures 4 to 8 As shown, the acquired flow field characteristics cover ice breakup, crack propagation, ice splash, and cavitation morphology evolution during interaction with the ice and ice during water entry, as well as velocity and pressure flow field information and projectile structural response characteristics. This data supports a variety of applications, such as projectile design optimization. By analyzing the stress and structural response of the projectile during high-speed ice penetration and water entry, it can guide improvements in projectile shape, material, and structure to enhance its penetration capability and impact resistance. Ice characteristics research: Flow field characteristics reveal ice breakup mechanisms and crack propagation patterns under high-speed impact, providing a deeper understanding of ice mechanical behavior and failure mechanisms. For ship navigation safety assessments, understanding the ice splash and cavitation morphology generated by projectile-ice interaction is crucial for assessing potential risks and formulating safety measures. Environmental protection strategy formulation: High-speed ice penetration can cause the spread of ice debris and ice fragments, impacting marine ecosystems. Analyzing flow field characteristics can assess these impacts and formulate appropriate environmental protection strategies.

[0123] Based on the same inventive concept, another embodiment of the present invention further provides a system for simulating high-speed penetration of a projectile into ice and water, comprising:

[0124] Water entry model module: establishes a high-speed water entry calculation model for projectiles based on the Euler-Lagrange coupling method;

[0125] Failure and fracture module: establishes an ice failure and fracture model based on the failure damage form of ice under high strain rate;

[0126] Strain module: Based on the constitutive relationship of metal structural materials, the Johnson-Cook constitutive equation and damage model are used to reflect the strain properties of metal materials;

[0127] Contact module: uses general contact to define the interaction between projectile and fluid, ice layer and fluid, and uses surface-to-surface contact to define the contact behavior between projectile and ice layer;

[0128] Coupling module: uses penalty function method to deal with the strong coupling process in the high-speed collision between projectile and ice layer;

[0129] Simulation Module: Based on the calculation model of high-speed projectile entry into water, ice failure and fracture model, strain properties of metal materials, interaction between projectile and fluid, ice and fluid, contact behavior between projectile and ice, and strong coupling process, the module numerically simulates the projectile penetrating ice and entering water to obtain information on cavitation evolution and ballistic characteristics.

[0130] The technical solutions of the above modules can refer to the technical solutions adopted in the various steps of the simulation method in the above embodiments, and will not be repeated here.

[0131] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with their meanings in the context of the prior art and, unless defined as such herein, will not be interpreted in an idealized or overly formal sense.

[0132] The meaning of "and / or" in this application means that both situations where each exists alone or both exist at the same time are included.

[0133] The above is only a preferred embodiment of the present invention. Through the above description, relevant personnel can make various changes and modifications without departing from the technical scope disclosed by the present invention. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims. Any equivalent replacement or change of the technical solution and inventive concept of the present invention should be covered by the protection scope of the present invention.

Claims

1. A method for simulating high-speed penetration of a projectile into water through ice, characterized in that: A computational model for high-speed projectile entry into water was established based on the Euler-Lagrangian coupling method. An ice failure fracture model is established based on the failure damage form of ice under high strain rate; According to the constitutive relationship of metal structural materials, the Johnson-Cook constitutive equation and damage model are used to reflect the strain properties of metal materials; The interaction between projectile and fluid, ice layer and fluid is defined by general contact, and the contact behavior between projectile and ice layer is defined by surface-to-surface contact. The penalty function method is used to deal with the strong coupling process in the high-speed collision between the projectile and the ice layer. Based on the calculation model of high-speed projectile entry into water, the ice failure and fracture model, the strain properties of metal materials, the interaction between projectile and fluid, ice and fluid, the contact behavior between projectile and ice, and the strong coupling process, a numerical simulation of projectile penetration through ice and entry into water is carried out to obtain information on cavitation evolution and ballistic characteristics.

2. A method for simulating high-speed penetration of a projectile into water through ice according to claim 1, characterized in that: A computational model for high-speed projectile entry into water is established based on the Euler-Lagrange coupling method, including: Based on the first property of Euler algorithm, the continuity equation, momentum conservation equation and energy conservation equation are obtained; Based on the second property of Lagrangian algorithm, the governing equation is obtained; Based on the continuity equation, momentum conservation equation, energy conservation equation, and control equation, the central difference algorithm is used to solve the dynamic equations to obtain acceleration and velocity representations; Based on the acceleration and velocity representation, the motion equation, water state and air state of the projectile entering the water at high speed are obtained as the calculation model of the projectile entering the water at high speed.

3. A method for simulating high-speed penetration of a projectile into water through ice according to claim 2, characterized in that: The first property includes: the Euler algorithm allows materials to flow through unit boundaries in a rigid grid, and different substances can exist in the rigid grid; the second property includes: the Lagrangian algorithm performs numerical solutions through discretization, and the deformation of the material and the grid nodes corresponds one-to-one and remains consistent.

4. A method for simulating high-speed penetration of a projectile into water through ice according to claim 2, characterized in that: Speed ​​is expressed as Acceleration is expressed as S represents the displacement, its subscript represents the corresponding moment, and Δt is the time step; The equation of motion is: Ma t + Cv t +KS t =Q t Where M is the mass matrix, C is the damping matrix, K is the stiffness matrix, Q t is the load vector; The state of water is defined by the linear Us-Up state equation, and the motion of water is simulated by the NS equation; The state of air adopts the ideal gas state equation.

5. A method for simulating high-speed penetration of a projectile into water through ice according to claim 1, characterized in that: An ice failure fracture model is established based on the failure mode of ice under high strain rate, including: At the beginning of the collision, the ice material first experiences an elastic stage, and the stress-strain relationship satisfies Hooke's law; The projectile-ice collision is a transient dynamic process. The ice layer continues to be compressed and instantly enters the plastic stage. Here, the Tsai-Wu criterion is used as the yield criterion for the ice material: The damage and cracks in the sea ice during the collision process are reflected through the accumulation of plastic deformation. When the damage accumulates to a critical value, the sea ice no longer has the bearing capacity and fails. At this time, the empirical failure criterion is adopted. The yield criterion and the empirical failure criterion constitute the ice layer failure fracture model.

6. A method for simulating high-speed penetration of a projectile into water through ice according to claim 5, characterized in that: The empirical failure criterion is: p<p c in, is the equivalent plastic strain, ε f is the failure strain, p is the hydrostatic pressure, and p c is the cut-off pressure. ε0 is the initial failure strain; ε0 is the initial failure strain; When sea ice is under compressive stress, When , the ice unit fails; Sea ice is in a tensile stress state when p<p c The ice unit fails.

7. A method for simulating high-speed penetration of a projectile into water through ice according to claim 1, characterized in that: According to the constitutive relationship of metal structural materials, the Johnson-Cook constitutive equation and damage model are used to reflect the strain properties of metal materials, including: Wherein, σ is the equivalent stress; A, B, C, n, and m are the relevant parameters of the material, A is the quasi-static yield stress, B is the strain hardening constant, C is the strain rate hardening coefficient, m is the temperature correlation coefficient, and n is the strain hardening exponent; ε is the equivalent plastic strain; T is the instantaneous absolute temperature of the material; T m is the melting temperature; T t is the conversion temperature.

8. A method for simulating high-speed penetration of a projectile into water through ice according to claim 1, characterized in that: The penalty function method is used to deal with the strong coupling process in the high-speed collision between the projectile and the ice layer, including: f n =k n g n f t =-sgn(g t )μ d (k n g n ) Among them, f n and f t represent normal force and tangential force respectively; g n and g t represent the normal and tangential penetration distances respectively; k n represents the normal penalty stiffness; μ d is the friction factor.

9. A method for simulating high-speed penetration of a projectile into water through ice according to claim 1, characterized in that: Cavitation evolution and ballistic characteristics information, including: cavitation evolution and ballistic characteristics information, including ice layer fragmentation, crack propagation, ice fragment splashing, cavitation morphology evolution under the interaction with the ice layer and ice fragments during water entry, velocity flow field, pressure flow field information and projectile structure response characteristics.

10. A high-speed projectile penetration and ice-breaking water simulation system, characterized in that: include: Water entry model module: establishes a high-speed water entry calculation model for projectiles based on the Euler-Lagrange coupling method; Failure and fracture module: establishes an ice failure and fracture model based on the failure damage form of ice under high strain rate; Strain module: Based on the constitutive relationship of metal structural materials, the Johnson-Cook constitutive equation and damage model are used to reflect the strain properties of metal materials; Contact module: uses general contact to define the interaction between projectile and fluid, ice layer and fluid, and uses surface-to-surface contact to define the contact behavior between projectile and ice layer; Coupling module: uses penalty function method to deal with the strong coupling process in the high-speed collision between projectile and ice layer; Simulation Module: Based on the calculation model of high-speed projectile entry into water, ice failure and fracture model, strain properties of metal materials, interaction between projectile and fluid, ice and fluid, contact behavior between projectile and ice, and strong coupling process, the module numerically simulates the projectile penetrating ice and entering water to obtain information on cavitation evolution and ballistic characteristics.

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