Method and system for predicting blast impact response of a metal foam filled y-shaped sandwich structure

Abstract

The application discloses an explosion impact response prediction method and system of a metal foam filled Y-shaped sandwich structure, and belongs to the technical field of dynamic response prediction of light protection structures. The method obtains structure geometric parameters, material parameters, boundary conditions and unit area explosion impulse, calculates Y-shaped web section area, area fraction and core layer equivalent density; initial velocity and common velocity are obtained based on momentum conservation; the normal compressive strength of the core layer is calculated by superimposing the plastic compressive contribution of the Y-shaped web and the platform stress contribution of the metal foam; the average compression strain of the core layer and the densification critical impulse are determined based on energy conservation; and the maximum central deflection and the structure response time are calculated based on the full solid support sandwich plate finite deflection rigid-plastic theory. The application can quickly predict the explosion impact response, and provides a basis for the optimal design of anti-explosion structures.

Description

Technical Field

[0001] This invention belongs to the field of dynamic response prediction technology for lightweight protective structures, specifically relating to a method and system for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure. It can be used for the preliminary design and parameter optimization of ship, aerospace, vehicle protection, and engineering explosion-proof structures. Background Technology

[0002] Lightweight sandwich structures typically consist of an upper panel, a lower panel, and a lightweight core layer. Due to their high specific strength, specific stiffness, and energy absorption capacity, they are widely used in shipbuilding, aerospace, vehicle protection, and explosion-proof engineering structures. The core layer of a Y-shaped sandwich structure can diffuse impact loads, exhibiting good load-bearing efficiency. Metal foam possesses plateau compression energy absorption characteristics; filling the cavity of the Y-shaped sandwich core layer with metal foam can improve the problems of traditional hollow Y-shaped core layers, such as local instability under explosive impact, insufficient energy absorption of the core layer, and a high risk of panel tearing.

[0003] However, existing research on metal foam-filled sandwich structures or Y-shaped sandwich structures mainly focuses on experimental analysis and finite element simulation under quasi-static compression, low-velocity impact, or localized loading. For explosive loads that can be equivalent to short-duration, high-intensity, uniformly distributed impulses, the structural response typically includes an early stage of rapid core layer compression and a subsequent stage of overall bending-tension with large deflection. The timescales, dominant deformation modes, and energy dissipation mechanisms of these two stages differ, making it difficult to accurately reflect the explosive impact response of metal foam-filled Y-shaped sandwich structures using only a single equivalent sandwich panel model.

[0004] Existing prediction methods have at least the following shortcomings: First, during the core compression stage, it is usually difficult to simultaneously consider the plastic compressive strength contribution of the Y-shaped web and the stress contribution of the metal foam platform, resulting in large deviations in the prediction of the average compressive strain and the critical impulse for densification of the core layer. Second, conventional equivalent sandwich panel models tend to ignore the asymmetric yield characteristics of the Y-shaped cross-section filled with metal foam, making it difficult to take into account both the overall bending response and the membrane force-dominated response. Third, parametric design often relies on a large number of transient finite element cases, resulting in high modeling and computational costs, which is not conducive to quickly evaluating the impact of parameters such as metal foam density, platform stress, Y-shaped web thickness, and Y-shaped branch angle on the blast resistance performance in the early stages of engineering design. Therefore, it is necessary to propose a prediction method for the blast impact response of metal foam-filled Y-shaped sandwich structures that can uniformly consider core compression, core densification, and overall large deflection response. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method and system for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure, which addresses the shortcomings of the prior art. This method and system solve the technical problem that it is difficult to quickly and uniformly predict the core layer compression, densification critical impulse, maximum center deflection and structural response time of a metal foam Y-shaped sandwich structure under explosion impact.

[0006] The present invention adopts the following technical solution: A method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure includes the following steps: Obtain the geometric parameters, material parameters, boundary conditions, and explosion impulse per unit area of ​​the structure to be predicted. The structure to be predicted includes an upper panel, a lower panel, a Y-shaped web, and a metal foam filling the core cavity between the Y-shaped webs. Calculate the cross-sectional area of ​​the Y-shaped web, the area fraction of the Y-shaped web in the core unit cell, and the equivalent density of the core based on the geometric parameters. The explosive impulse per unit area is equivalent to the initial uniform velocity of the upper panel, and the common velocity of the upper panel, lower panel and core layer at the end of core layer compression is calculated based on the conservation of momentum. Calculate the normal compressive strength of the core layer based on the plastic compressive strength contribution of the Y-shaped web and the stress contribution of the metal foam platform; Based on the relationship that the kinetic energy lost during the core compression stage is equal to the energy consumed during the plastic compression of the core, the average compressive strain of the core is calculated and compared with the densification strain of the metal foam to determine whether the core is densified. The critical impulse for core densification is determined under the condition that the average compressive strain of the core layer is equal to the densification strain of the metal foam. After the core layer compression is completed, based on the finite deflection rigid-plastic theory of fully fixed sandwich panels, combined with the plastic hinge displacement field and the cross-sectional yield trajectory or membrane force-dominated approximation of the Y-shaped section filled with metal foam, the maximum central deflection and structural response time are calculated, and the prediction results are output.

[0007] Furthermore, the geometric parameters include the structural half-length, half-width, thickness of the upper and lower panels, half-thickness of the core layer, width of the core layer unit cell, thickness of the Y-shaped web, and the angle between the Y-shaped branches and the horizontal plane; the material parameters include the density and yield strength of the upper and lower panels, the density and yield strength of the Y-shaped web, the density of the metal foam, the stress of the metal foam platform, and the densification strain of the metal foam; the boundary condition is a fully fixed boundary, and the explosive load is equivalent to a uniformly distributed short-time impulse.

[0008] Further, the calculation of the cross-sectional area of ​​the Y-shaped web, the area fraction of the Y-shaped web in the core cell, and the equivalent density of the core layer includes: determining the cross-sectional area of ​​the Y-shaped web in the core cell based on the thickness of the Y-shaped web, the width of the core cell, the half-thickness of the core layer, and the angle between the Y-shaped branches and the horizontal plane; determining the area fraction based on the ratio of the cross-sectional area to the total cross-sectional area of ​​the core cell; and determining the equivalent density of the core layer based on the area fraction, the density of the Y-shaped web, and the density of the metal foam.

[0009] Furthermore, the explosive impulse per unit area is equivalent to the initial uniform distribution velocity of the upper panel, which includes dividing the explosive impulse per unit area by the mass per unit area of ​​the upper panel to obtain the initial uniform distribution velocity of the upper panel; the common velocity is calculated by dividing the explosive impulse per unit area by the total mass per unit area of ​​the upper panel, the lower panel, and the core layer to obtain the common velocity.

[0010] Further, the calculation of the normal compressive strength of the core layer includes: determining the plastic compressive strength contribution of the Y-shaped web based on the angle range of the angle between the Y-shaped branch and the horizontal plane; and superimposing the plastic compressive strength contribution of the Y-shaped web with the stress contribution of the metal foam platform determined by the stress of the metal foam platform and the area ratio of the metal foam to obtain the normal compressive strength of the core layer.

[0011] Further, the calculation of the average compressive strain of the core layer includes: determining the dimensionless impulse based on the explosion impulse per unit area, the overall mass per unit area, and the material parameters of the upper and lower panels, and determining the mass ratio based on the equivalent density of the core layer, the half-thickness of the core layer, and the mass per unit area of ​​the upper panel; calculating the average compressive strain of the core layer based on the dimensionless impulse, the mass ratio, the half-thickness of the core layer, and the normal compressive strength of the core layer; when the average compressive strain of the core layer is greater than the densification strain of the metal foam, the average compressive strain of the core layer is taken as the densification strain of the metal foam.

[0012] Further, determining the critical impulse for core densification includes: setting the average compressive strain of the core layer equal to the densification strain of the metal foam, and back-calculating the dimensionless critical impulse when the core layer reaches the densification state; comparing the actual dimensionless impulse with the dimensionless critical impulse to determine whether the structure to be predicted will undergo core densification under a given explosive impact.

[0013] Further, the calculation of the maximum central deflection and structural response time includes: determining the plate dimension parameters and plastic hinge folding angle based on the half-length and half-width of the structure; calculating the fully plastic axial force and fully plastic bending moment based on the geometric and material parameters of the Y-shaped section filled with metal foam; determining the section yield trajectory based on the fully plastic axial force and the fully plastic bending moment, or using the membrane force dominant approximation to calculate the dimensionless maximum central deflection and dimensionless response time, and converting them into the dimensional maximum central deflection and dimensional structural response time.

[0014] Furthermore, the method includes finite element verification of the prediction results: establishing a finite element model consistent with the input parameters, setting the upper and lower panels and the Y-shaped web as shell elements, setting the metal foam as a three-dimensional solid element, setting binding constraints between the upper and lower panels, the Y-shaped web and the metal foam, and applying the initial uniform velocity of the upper panel to the upper panel; extracting the velocity time history, core layer compression, center deflection time history and maximum center deflection, and comparing them with the prediction results; when the deviation exceeds a preset threshold, correcting the metal foam platform stress, metal foam densification strain, Y-shaped web yield strength or cross-sectional yield trajectory parameters and re-predicting.

[0015] Secondly, embodiments of the present invention provide an explosion impact response prediction system for a metal foam-filled Y-shaped sandwich structure, comprising: The parameter acquisition module is used to acquire the geometric parameters, material parameters, boundary conditions and explosion impulse per unit area of ​​the structure to be predicted. The structure to be predicted includes an upper panel, a lower panel, a Y-shaped web and a metal foam filled in the core cavity between the Y-shaped webs. The core layer equivalent parameter calculation module is used to calculate the cross-sectional area of ​​the Y-shaped web, the area fraction of the Y-shaped web in the core layer unit cell, and the core layer equivalent density based on the geometric parameters. The velocity calculation module is used to convert the explosive impulse per unit area into the initial uniform velocity of the upper panel, and to calculate the common velocity of the upper panel, lower panel and core layer at the end of core layer compression based on the conservation of momentum. The compressive strength calculation module is used to calculate the normal compressive strength of the core layer based on the plastic compressive strength contribution of the Y-shaped web and the stress contribution of the metal foam platform. The densification judgment module is used to calculate the average compressive strain of the core layer based on the relationship that the kinetic energy lost during the core layer compression stage is equal to the energy consumed by the plastic compression of the core layer, and to judge whether the core layer is densified based on the comparison result of the average compressive strain of the core layer and the densification strain of the metal foam. The critical impulse calculation module is used to determine the critical impulse of the core layer densification under the condition that the average compressive strain of the core layer is equal to the densification strain of the metal foam. The overall response calculation module is used to calculate the maximum central deflection and structural response time after the core layer compression is completed, based on the finite deflection rigid-plastic theory of fully fixed sandwich panels, combined with the plastic hinge displacement field and the cross-sectional yield trajectory or membrane force dominant approximation of the Y-shaped section filled with metal foam. The result output module is used to output the average compressive strain of the core layer, the critical impulse for core layer densification, the maximum central deflection, and the structural response time.

[0016] Thirdly, a computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of the above-described method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure.

[0017] Fourthly, embodiments of the present invention provide a computer-readable storage medium including a computer program, which, when executed by a processor, implements the steps of the above-described method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure.

[0018] Fifthly, a chip includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of the above-described method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure.

[0019] In a sixth aspect, embodiments of the present invention provide an electronic device, including a computer program, which, when executed by the electronic device, implements the steps of the above-described method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure.

[0020] Compared with the prior art, the present invention has at least the following beneficial effects: A method for predicting the explosion impact response of a Y-shaped sandwich structure filled with metal foam is proposed. Based on the mechanical law that the sandwich structure first undergoes core layer compression and energy absorption, followed by overall bending-tensile deformation under explosion impact, the response process is divided into two stages for prediction. In the core layer compression stage, the velocity state after the impulse input is determined by momentum conservation, and the lost kinetic energy is converted into core layer plastic compression energy dissipation by energy conservation. Combining the plastic compressive strength contribution of the Y-shaped web and the stress contribution of the metal foam platform, the average compressive strain of the core layer can be calculated and the densification state can be determined. In the overall response stage, the maximum central deflection and structural response time are calculated based on the finite deflection rigid-plastic theory of fully fixed sandwich panels. This method can simultaneously evaluate the core layer's energy absorption capacity and the overall bending and tensile deformation resistance, reducing the reliance on a large number of transient finite element simulations and improving the efficiency of optimizing explosion-resistant structural parameters.

[0021] Furthermore, the input boundaries of the prediction model are clearly defined. By simultaneously incorporating structural dimensions, web angle, material strength, foam density, plateau stress, and densification strain, the prediction results can directly reflect the influence of key structural and material parameters on the blast resistance response.

[0022] Furthermore, the discrete Y-shaped web and continuous metal foam filling are transformed into equivalent core layer parameters that can be used for dynamic response calculations. This process preserves the influence of the Y-shaped web geometry on the core layer mass and load-bearing capacity, providing a basis for subsequent calculations of velocity, compressive strength, and energy dissipation.

[0023] Furthermore, the conservation of momentum is used to describe the initial momentum input of the short-duration explosive impulse to the sandwich structure. This step can transform the explosive load into the initial conditions of structural dynamics and distinguish between the initial motion of the upper panel and the overall common motion state after the core layer compression is completed.

[0024] Furthermore, the plastic compressive resistance of the Y-shaped web and the compressive energy absorption of the metal foam platform are simultaneously characterized. By determining the compressive contribution of the web based on the angle interval of the Y-shaped branches and superimposing the stress contribution of the metal foam platform, the true source of resistance during the core compression stage can be more accurately reflected, reducing the error in densification judgment.

[0025] Furthermore, the early energy absorption of the core layer is evaluated by utilizing the correlation between kinetic energy loss and energy dissipation during plastic compression. When the calculated average compressive strain of the core layer exceeds the densification strain of the metal foam, it is limited to the densification strain, which helps to avoid the predicted results during the compression stage exceeding the actual deformation capacity of the metal foam.

[0026] Furthermore, a criterion is established between the explosive impulse and the densification state of the core layer. By setting the average compressive strain of the core layer equal to the densification strain of the metal foam and back-calculating the critical impulse, it is possible to quickly determine whether the target structure densifies prematurely under a given explosive impact, providing a basis for selecting foam density, plateau stress, and web parameters.

[0027] Furthermore, the overall large deflection response after core compression is described. By introducing the plastic hinge displacement field, fully plastic axial force, fully plastic bending moment, section yield trajectory, or membrane force-dominated approximation, the yield characteristics of the Y-shaped section filled with metal foam and the large deformation bearing mechanism of the fully fixed sandwich panel can be taken into account.

[0028] Furthermore, the analytical prediction results are verified and corrected. By establishing a finite element model consistent with the input parameters, the velocity time history, core compression, center deflection time history, and maximum center deflection are extracted. When the deviation exceeds a preset threshold, the material or yield trajectory parameters are corrected, which can improve the reliability of the prediction results under specific engineering parameters.

[0029] It is understood that the beneficial effects of the second to sixth aspects mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here.

[0030] In summary, this invention models the core compression and overall large deflection response in stages, taking into account the compressive energy absorption effects of the Y-shaped web and the metal foam. It can quickly obtain the compressive strain, densification critical impulse, maximum deflection, and response time, reducing the dependence on finite element method and providing a direct basis for optimizing the metal foam density, plateau stress, web thickness, and included angle.

[0031] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0032] Figure 1 This is a flowchart of the method of the present invention; Figure 2 A global schematic diagram of a Y-shaped sandwich panel filled with fully fixed metal foam under explosive load; Figure 3 Longitudinal velocity field distribution contour map of a 1 / 4 square fully fixed metal foam-filled Y-shaped sandwich panel under explosive load; Figure 4 The effect of the yield strength of the metal foam core material on the dimensionless maximum central deflection-applied pulse relationship curve; Figure 5 A schematic diagram of a computer device provided in an embodiment of the present invention; Figure 6 This is a block diagram of a chip provided according to an embodiment of the present invention.

[0033] Among them, 60. Computer equipment; 61. Processor; 62. Memory; 63. Computer program; 600. Electronic device; 610. Processing unit; 620. Storage unit; 6201. Random access memory unit; 6202. Cache memory unit; 6203. Read-only memory unit; 6204. Program / utility; 6205. Program module; 630. Bus; 640. Display unit; 650. Input / output interface; 660. Network adapter; 700. External device. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] In the description of this invention, it should be understood that the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0036] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0037] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Additionally, the character " / " in this invention generally indicates that the preceding and following objects have an "or" relationship.

[0038] It should be understood that although terms such as first, second, third, etc., may be used in the embodiments of the present invention to describe the preset range, these preset ranges should not be limited to these terms. These terms are only used to distinguish the preset ranges from one another. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0039] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0040] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0041] This invention provides a method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure. First, the geometric parameters, material parameters, and explosion impulse per unit area of ​​the metal foam Y-shaped sandwich structure are obtained. The cross-sectional area and area fraction of the Y-shaped web, and the equivalent density of the core layer are calculated. Based on momentum conservation, the initial velocity of the upper panel and the common velocity at the end of core layer compression are determined. The plastic compressive strength contribution of the Y-shaped web is superimposed with the compressive strength contribution of the metal foam platform to calculate the normal compressive strength of the core layer. Furthermore, based on energy conservation, the average compressive strain of the core layer and the critical impulse for core layer densification are obtained. Subsequently, based on the finite deflection rigid-plastic theory of fully fixed sandwich panels, the cross-sectional yield trajectory, or the membrane force-dominated approximation, the maximum central deflection and structural response time are calculated. This invention can rapidly predict the core layer compression, densification, and overall large deflection response of a metal foam Y-shaped sandwich structure under an idealized explosion impulse, providing a basis for the explosion-resistant optimization design of metal foam strength, metal foam density, Y-shaped web thickness, and web angle.

[0042] Please see Figure 1 The present invention discloses a method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure, comprising the following steps: S1. Obtain input parameters Obtain the geometric parameters, material parameters, boundary conditions, and explosion impulse parameters of the Y-shaped metal foam sandwich structure. Geometric parameters include the half-length of the structure. L Half width B Thickness of top and bottom panels h Core layer half thickness c Core cell width b Y-shaped web thickness a The angle between the Y-shaped branch and the horizontal plane θ Material parameters include the density of the upper and lower panels. ρ f Yield strength σ f Y-shaped web density ρ fc Yield strength σ fc Metal foam density ρ c Platform stress σ c and densification strain ε D The explosive impulse parameter is the impulse per unit area I. Preferably, the structure has a fully fixed boundary, and the explosive load is equivalent to a uniformly distributed short-time impulse.

[0043] S2, Calculate the equivalent geometric parameters of the core layer. according to Figure 2 Calculate the cross-sectional area of ​​the Y-shaped web from the shown core unit cell. S Y Core area fractionf Equivalent density of Y-shaped sandwich core layer with metal foam ρ z .

[0044] The formula for calculating the cross-sectional area SY of a Y-shaped web is:

[0045] area fraction f and core equivalent density ρ z They are respectively:

[0046]

[0047] in, S Y 2 is the cross-sectional area of ​​the Y-shaped web in the core unit cell; bc This represents the total cross-sectional area of ​​the core unit cell; f This represents the area fraction of the Y-shaped web within the core unit cell; ρ z The equivalent density of the Y-shaped sandwich core layer of the metal foam is given.

[0048] S3, Calculate the velocity during the core compression stage. The explosive impulse is first equivalent to the initial uniform velocity acting on the upper panel. V 0, and then calculate the common velocity of the upper panel, lower panel, and core layer at the end of core layer compression based on the law of conservation of momentum. V f .

[0049] Initial velocity of the upper panel V 0 and the combined velocity at the end of core compression V f They are respectively:

[0050]

[0051] in, I The explosive impulse per unit area; ρ f h Mass per unit area of ​​the upper panel; 2 ρ f h +2 ρ z c The mass per unit area of ​​the overall sandwich structure.

[0052] S4. Calculate the normal compressive strength of the core layer. The normal compressive strength of the Y-shaped web is obtained by superimposing the plastic compressive strength of the metal foam platform with the stress contribution of the Y-shaped sandwich core. σ nY .

[0053] Introducing dimensionless variables ā = a / h , = b / h , = c / h , fc = σ fc / σ f , c = σ c / σ f , n = σ nY / σ f Dimensionless normal compressive strength of Y-shaped sandwich core layer of metal foam nY Calculated according to the following relationship:

[0054] The above segmented relationship reflects the influence of the Y-shaped web angle on the core compression deformation mode, and takes the metal foam platform stress as the compressive strength contribution of the continuous filling phase in the core.

[0055] S5. Calculate the average compressive strain of the core layer and determine its densification. By utilizing the relationship that the kinetic energy lost during the core compression stage is equal to the energy dissipated during the plastic compression of the core, the average compressive strain of the core is calculated. ε c ;when ε c Greater than the densification strain of metal foam ε D At that time, ε c Take as ε D And it was determined that the core layer had entered a densification state.

[0056] Define dimensionless impulse and mass ratio for: ,

[0057] The average compressive strain of the core layer can be obtained from the law of energy conservation. ε c :

[0058] when ε c < ε D At that time, the core layer was not yet fully densified; when ε c = ε D At this point, the core layer reaches a dense state, and subsequent increases in impulse mainly cause overall bending-tensile deformation or local damage.

[0059] S6. Calculate the critical impulse for core densification. make ε c = ε D The dimensionless critical impulse when the core layer reaches a densified state is obtained by reverse calculation. 0, which can be further converted to a dimensional critical impulse if necessary. I 0.

[0060] make ε c = ε D The dimensionless critical impulse for core densification was obtained. 0:

[0061] By comparing actual dimensionless impulse With critical impulse 0, can quickly determine whether the target structure has undergone core densification under a given explosive impact.

[0062] S7. Calculate the overall bending-tensile response. After the core compression stage, the remaining kinetic energy is used to drive the overall deformation of the fully fixed sandwich panel. The maximum central deflection is calculated based on the plastic hinge displacement field, the section yield trajectory, and the membrane force-dominated approximation. W m and structural response time T m .

[0063] After the core layer compression stage, the overall response was calculated using the finite deflection rigid-plastic theory of fully fixed sandwich panels. The panel surface was divided into rigid regions separated by plastic hinge lines, and dimensional parameters were defined. β = B / L And the folding angle φ: β = B / L ,

[0064] Calculate the fully plastic axial force based on the geometric and material parameters of the Y-shaped cross-section of the metal foam. N pb Fully plastic bending moment M pb The yield trajectory can be determined by using internal approximation and external approximation to give the lower and upper bounds of the maximum central deflection, respectively, or by using the membrane force-dominated approximation during the large deflection stage.

[0065] Preferably, a dimensionless stiffness parameter is introduced into the membrane force-dominated approximation. ā 2. Calculate the dimensionless maximum central deflection using the following formula. m and dimensionless response time m :

[0066]

[0067] Dimensionless maximum central deflection m and structural response time m Convert using the following formula: ,

[0068] in, ā 2. Composed of structural unit area mass and fully plastic axial force N pb The structural dimensions and plastic hinge configuration are determined. For working conditions requiring higher precision, the inner and outer approximations of the yield trajectory can be substituted into the rigid-plastic governing equations to obtain the upper and lower bound prediction results, respectively.

[0069] S8. Output the prediction results and perform optional verification. Output core average compressive strain ε c Critical impulse for densification I 0 or 0. Maximum central deflection W m Dimensionless maximum central deflection m Structural response time T m And parameter sensitivity curves; when necessary, establish a finite element model to verify the prediction results.

[0070] In another embodiment of the present invention, an explosion impact response prediction system for a metal foam-filled Y-shaped sandwich structure is provided. This system can be used to implement the above-mentioned explosion impact response prediction method for the metal foam-filled Y-shaped sandwich structure. Specifically, the explosion impact response prediction system for the metal foam-filled Y-shaped sandwich structure includes a parameter acquisition module, a core layer equivalent parameter calculation module, a velocity calculation module, a compressive strength calculation module, a densification judgment module, a critical impulse calculation module, an overall response calculation module, and a result output module.

[0071] The parameter acquisition module is used to acquire the geometric parameters, material parameters, boundary conditions and explosion impulse per unit area of ​​the structure to be predicted. The structure to be predicted includes an upper panel, a lower panel, a Y-shaped web and a metal foam filled in the core cavity between the Y-shaped webs. The core layer equivalent parameter calculation module is used to calculate the cross-sectional area of ​​the Y-shaped web, the area fraction of the Y-shaped web in the core layer unit cell, and the core layer equivalent density based on the geometric parameters. The velocity calculation module is used to convert the explosive impulse per unit area into the initial uniform velocity of the upper panel, and to calculate the common velocity of the upper panel, lower panel and core layer at the end of core layer compression based on the conservation of momentum. The compressive strength calculation module is used to calculate the normal compressive strength of the core layer based on the plastic compressive strength contribution of the Y-shaped web and the stress contribution of the metal foam platform. The densification judgment module is used to calculate the average compressive strain of the core layer based on the relationship that the kinetic energy lost during the core layer compression stage is equal to the energy consumed by the plastic compression of the core layer, and to judge whether the core layer is densified based on the comparison result of the average compressive strain of the core layer and the densification strain of the metal foam. The critical impulse calculation module is used to determine the critical impulse of the core layer densification under the condition that the average compressive strain of the core layer is equal to the densification strain of the metal foam. The overall response calculation module is used to calculate the maximum central deflection and structural response time after the core layer compression is completed, based on the finite deflection rigid-plastic theory of fully fixed sandwich panels, combined with the plastic hinge displacement field and the cross-sectional yield trajectory or membrane force dominant approximation of the Y-shaped section filled with metal foam. The result output module is used to output the average compressive strain of the core layer, the critical impulse for core layer densification, the maximum central deflection, and the structural response time.

[0072] This invention provides a terminal device comprising a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, graphics processing units (GPUs), tensor processing units (TPUs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions to achieve a corresponding method flow or corresponding function. The processor described in this embodiment can be used in the operation of an explosion impact response prediction method for a metal foam-filled Y-shaped sandwich structure, including: Obtain the geometric parameters, material parameters, boundary conditions, and explosion impulse per unit area of ​​the structure to be predicted. The structure includes an upper panel, a lower panel, a Y-shaped web, and metal foam filling the core cavity between the Y-shaped webs. Calculate the cross-sectional area of ​​the Y-shaped web, the area fraction of the Y-shaped web in the core unit cell, and the equivalent density of the core layer based on the geometric parameters. Equivalently represent the explosion impulse per unit area as the initial uniform velocity of the upper panel, and calculate the common velocity of the upper panel, lower panel, and core layer at the end of core compression based on momentum conservation. Calculate the plastic compressive strength contribution of the Y-shaped web and the stress contribution of the metal foam platform. Calculate the normal compressive strength of the core layer; based on the relationship that the kinetic energy loss during the core layer compression stage is equal to the energy dissipation during the plastic compression of the core layer, calculate the average compressive strain of the core layer and compare it with the densification strain of the metal foam to determine whether the core layer is densified; determine the critical impulse for core layer densification based on the condition that the average compressive strain of the core layer is equal to the densification strain of the metal foam; after the core layer compression is completed, based on the finite deflection rigid-plastic theory of fully fixed sandwich panels, combined with the plastic hinge displacement field and the cross-sectional yield trajectory or membrane force dominant approximation of the Y-shaped section filled with metal foam, calculate the maximum central deflection and structural response time, and output the prediction results.

[0073] Please see Figure 5The terminal device is a computer device. In this embodiment, the computer device 60 includes a processor 61, a memory 62, and a computer program 63 stored in the memory 62 and executable on the processor 61. When executed by the processor 61, the computer program 63 implements the explosion impact response prediction method for the metal foam-filled Y-shaped sandwich structure in this embodiment. To avoid repetition, details are omitted here. Alternatively, when executed by the processor 61, the computer program 63 implements the functions of each model / unit in the explosion impact response prediction system for the metal foam-filled Y-shaped sandwich structure in this embodiment. To avoid repetition, details are omitted here.

[0074] Computer device 60 can be a desktop computer, laptop, handheld computer, cloud server, or other computing device. Computer device 60 may include, but is not limited to, a processor 61 and a memory 62. Those skilled in the art will understand that... Figure 5 This is merely an example of computer device 60 and does not constitute a limitation on computer device 60. It may include more or fewer components than shown, or combine certain components, or different components. For example, computer device may also include input / output devices, network access devices, buses, etc.

[0075] The processor 61 may be a Central Processing Unit (CPU), or other general-purpose processors, graphics processing units (GPUs), tensor processing units (TPUs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0076] The memory 62 can be an internal storage unit of the computer device 60, such as a hard disk or memory of the computer device 60. The memory 62 can also be an external storage device of the computer device 60, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc. equipped on the computer device 60.

[0077] Furthermore, the memory 62 may include both internal storage units of the computer device 60 and external storage devices. The memory 62 is used to store computer programs and other programs and data required by the computer device. The memory 62 can also be used to temporarily store data that has been output or will be output.

[0078] Please see Figure 6 The terminal device is an electronic device 600, which is manifested in the form of a general-purpose computing device. The components of the electronic device may include, but are not limited to: at least one processing unit 610, at least one storage unit 620, a bus 630 connecting different platform components (including storage unit 620 and processing unit 610), a display unit 640, etc.

[0079] The storage unit stores program code, which can be executed by the processing unit 610 to perform the steps described in the method section of this specification according to various exemplary embodiments of the present invention. For example, the processing unit 610 can perform actions such as... Figure 1 The steps are shown in the figure.

[0080] Storage unit 620 may include readable media in the form of volatile storage units, such as random access memory (RAM) 6201 and / or cache memory 6202, and may further include read-only memory (ROM) 6203.

[0081] Storage unit 620 may also include a program / utility 6204 having a set (at least one) program module 6205, such program module 6205 including but not limited to: operating system, one or more application programs, other program modules and program data, each or some combination of these examples may include an implementation of a network environment.

[0082] Bus 630 can represent one or more of several types of bus structures, including a memory cell bus or memory cell controller, a peripheral bus, a graphics acceleration port, a processing unit, or a local bus using any of the multiple bus structures.

[0083] Electronic device 600 can also communicate with one or more external devices 700 (e.g., keyboard, pointing device, Bluetooth device, etc.), and with one or more devices that enable a user to interact with electronic device 600, and / or with any device that enables electronic device 600 to communicate with one or more other computing devices (e.g., router, modem). This communication can be performed via input / output interface 650. Furthermore, electronic device 600 can also communicate with one or more networks (e.g., local area network, wide area network, and / or public network, such as the Internet) via network adapter 660. Network adapter 660 can communicate with other modules of electronic device 600 via bus 630. It should be understood that, although not shown in the figures, other hardware and / or software modules can be used in conjunction with electronic device 600, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage platforms.

[0084] This invention also provides a storage medium, specifically a computer-readable storage medium, which is a memory device in a terminal device for storing programs and data. It is understood that the computer-readable storage medium here can include both built-in storage media in the terminal device and extended storage media supported by the terminal device; it can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, the storage space also stores one or more instructions suitable for loading and execution by a processor, which can be one or more computer programs (including program code). More specific examples of the computer-readable storage medium include: an electrical connection with one or more wires, a portable disk, a hard disk, random access memory, read-only memory, erasable programmable read-only memory, optical fiber, portable compact disk read-only memory, optical storage device, magnetic storage device, or any suitable combination thereof.

[0085] Computer-readable storage media also include data signals propagated in baseband or as part of a carrier wave, carrying readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable storage medium can also be any readable medium other than a readable storage medium that can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the readable storage medium can be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, radio frequency, etc., or any suitable combination thereof.

[0086] Program code for performing the operations of this invention can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java and C++, and conventional procedural programming languages ​​such as C or similar languages. The program code can execute entirely on the user's computing device, partially on the user's device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0087] One or more instructions stored in a computer-readable storage medium can be loaded and executed by a processor to implement the corresponding steps of the explosion impact response prediction method for the metal foam-filled Y-shaped sandwich structure in the above embodiments; one or more instructions in the computer-readable storage medium are loaded and executed by the processor to perform the following steps: Obtain the geometric parameters, material parameters, boundary conditions, and explosion impulse per unit area of ​​the structure to be predicted. The structure includes an upper panel, a lower panel, a Y-shaped web, and metal foam filling the core cavity between the Y-shaped webs. Calculate the cross-sectional area of ​​the Y-shaped web, the area fraction of the Y-shaped web in the core unit cell, and the equivalent density of the core layer based on the geometric parameters. Equivalently represent the explosion impulse per unit area as the initial uniform velocity of the upper panel, and calculate the common velocity of the upper panel, lower panel, and core layer at the end of core compression based on momentum conservation. Calculate the plastic compressive strength contribution of the Y-shaped web and the stress contribution of the metal foam platform. Calculate the normal compressive strength of the core layer; based on the relationship that the kinetic energy loss during the core layer compression stage is equal to the energy dissipation during the plastic compression of the core layer, calculate the average compressive strain of the core layer and compare it with the densification strain of the metal foam to determine whether the core layer is densified; determine the critical impulse for core layer densification based on the condition that the average compressive strain of the core layer is equal to the densification strain of the metal foam; after the core layer compression is completed, based on the finite deflection rigid-plastic theory of fully fixed sandwich panels, combined with the plastic hinge displacement field and the cross-sectional yield trajectory or membrane force dominant approximation of the Y-shaped section filled with metal foam, calculate the maximum central deflection and structural response time, and output the prediction results.

[0088] The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0089] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0090] The present invention is applicable to the following preferred parameter range, which can be adjusted according to material tests and structural dimensions in actual engineering.

[0091]

[0092] To verify or correct the prediction results, a finite element model consistent with the parameters in step S1 can be established. Preferably, a quarter-size model is established using structural and load symmetry; shell elements are used for the upper and lower panels and the Y-shaped web, while three-dimensional solid elements are used for the metal foam; binding constraints are applied between the upper and lower panels, the Y-shaped web, and the metal foam; the external boundary is set as fully fixed, and corresponding symmetry boundaries are set for the two symmetry planes; a uniformly distributed initial velocity V0 is applied to the upper panel to obtain an equivalent explosive impulse. The velocity time history of the upper and lower panels, the core compression, the center deflection time history, and the maximum center deflection are extracted and compared with the results of steps S5 to S7.

[0093] When the deviation between the finite element results and the analytical prediction results exceeds a preset threshold, the stress, densification strain, Y-shaped web yield strength, or section yield trajectory parameters of the metal foam platform can be corrected, and the prediction results can be recalculated. The preset threshold can be taken as 5% to 20%.

[0094] Please see Figure 3 Under the constraints of fully fixed and symmetrical boundaries, the longitudinal velocity of the structure exhibits a continuous gradient distribution along the plate surface. The velocity is lower near the fixed boundary and higher further away from the boundary but closer to the center of the plate. This indicates that after the explosive impulse input, the structure does not only experience localized indentation but also forms an overall bending-tensile response controlled by the boundary constraints. This velocity field distribution is consistent with the deformation assumption in the finite deflection rigid-plastic theory of fully fixed sandwich panels, which states that "plastic hinges separate rigid regions and drive the central region to generate a large deflection." This demonstrates that the calculation of the maximum central deflection and structural response time after the core layer compression in this invention has a clear mechanical basis.

[0095] Figure 3 Furthermore, it is shown that when using a 1 / 4 symmetric model for finite element verification, the velocity field exhibits a regular distribution about the symmetric boundary, and the fixed boundary has a significant constraint effect on the structural motion, reflecting the overall dynamic response characteristics of the actual fully fixed sandwich panel under the action of a uniformly distributed short-time explosive impulse. Therefore, by extracting the velocity time history, core compression, center deflection time history, and maximum center deflection, and comparing them with the analytical prediction results of this invention, it can be verified whether the established two-stage prediction model can simultaneously describe the early core compression and subsequent large overall deflection deformation.

[0096] Please see Figure 4 Under different yield strength conditions of the metal foam core material, the dimensionless maximum central deflection increases with the increase of the dimensionless applied pulse, indicating that the larger the explosion impulse, the more obvious the overall bending-tensile deformation of the structure. Meanwhile, as the yield strength of the metal foam core material increases, the dimensionless maximum central deflection under the same dimensionless applied pulse decreases, indicating that increasing the platform stress or yield strength of the metal foam can enhance the compressive energy absorption capacity of the core layer, reduce the deformation requirement transferred to the overall bending-tensile stage, and thus reduce the maximum central deflection of the structure.

[0097] Depend on Figure 4 It can also be concluded that the yield strength of the metal foam core material is a crucial parameter affecting the blast resistance of a metal foam-filled Y-shaped sandwich structure. This invention incorporates the contribution of metal foam plateau stress into the calculation of the core layer's normal compressive strength, and continuously transmits the influence of this parameter in the calculations of core layer compressive strain, densification critical impulse, and maximum central deflection. This allows the prediction results to directly reflect the impact of changes in metal foam material parameters on the structure's blast resistance. Compared to methods relying solely on finite element analysis for each working condition, this invention can quickly obtain the response variation trends under different foam yield strengths or plateau stress conditions, facilitating material selection and parameter optimization in the early design stages.

[0098] Figure 3 This verifies the rationality of using the finite deflection rigid-plastic theory of fully fixed sandwich panels to describe the overall bending-tensile response in this invention. Figure 4 This demonstrates that the yield strength of the metal foam core material has a significant regulatory effect on the maximum central deflection. Both findings indicate that this invention can not only output quantitative indicators such as the average compressive strain of the core layer, the critical impulse for densification, the maximum central deflection, and the structural response time, but also reveal the influence of metal foam strength parameters on blast resistance performance. This provides a basis for the rapid prediction, finite element verification, and blast-resistant optimization design of metal foam-filled Y-shaped sandwich structures.

[0099] In summary, this invention provides a method and system for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure. Addressing the need for rapid response prediction of metal foam-filled Y-shaped sandwich structures under explosion impact, the invention divides the structural response into a core layer compression stage and an overall bending-tension stage, establishing calculation relationships for momentum, energy, and rigid-plastic response respectively. This allows for a clearer reflection of the structural process from localized compression and energy absorption to overall large deflection deformation after an explosion impulse input. In the core layer compression stage, this invention simultaneously considers the plastic compressive strength contribution of the Y-shaped web and the stress contribution of the metal foam platform, making the calculations of the core layer's normal compressive strength, average compressive strain, and densification critical impulse more closely aligned with the actual load-bearing mechanism of the metal foam-filled Y-shaped core. In the overall response stage, this invention combines the plastic hinge displacement field, cross-sectional yield trajectory, or membrane force-dominated approximation to obtain the maximum central deflection and structural response time. Compared with methods that rely entirely on finite element simulation, this invention has clear input parameters, intuitive output indicators, and high computational efficiency. It can be used to quickly screen parameters such as metal foam density, platform stress, web thickness, and web angle in the early stages of design, and the prediction results can be further corrected through finite element verification.

[0100] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0101] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0102] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed in this invention can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0103] In the embodiments provided by this invention, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0104] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0105] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0106] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random-access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0107] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus, and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0108] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0109] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0110] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure, characterized in that, Includes the following steps: Obtain the geometric parameters, material parameters, boundary conditions, and explosion impulse per unit area of ​​the structure to be predicted. The structure to be predicted includes an upper panel, a lower panel, a Y-shaped web, and a metal foam filling the core cavity between the Y-shaped webs. Calculate the cross-sectional area of ​​the Y-shaped web, the area fraction of the Y-shaped web in the core unit cell, and the equivalent density of the core based on the geometric parameters. The explosive impulse per unit area is equivalent to the initial uniform velocity of the upper panel, and the common velocity of the upper panel, lower panel and core layer at the end of core layer compression is calculated based on the conservation of momentum. Calculate the normal compressive strength of the core layer based on the plastic compressive strength contribution of the Y-shaped web and the stress contribution of the metal foam platform; Based on the relationship that the kinetic energy lost during the core compression stage is equal to the energy consumed during the plastic compression of the core, the average compressive strain of the core is calculated and compared with the densification strain of the metal foam to determine whether the core is densified. The critical impulse for core densification is determined under the condition that the average compressive strain of the core layer is equal to the densification strain of the metal foam. After the core layer compression is completed, based on the finite deflection rigid-plastic theory of fully fixed sandwich panels, combined with the plastic hinge displacement field and the cross-sectional yield trajectory or membrane force-dominated approximation of the Y-shaped section filled with metal foam, the maximum central deflection and structural response time are calculated, and the prediction results are output.

2. The method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure according to claim 1, characterized in that, The geometric parameters include the half-length, half-width, thickness of the upper and lower panels, half-thickness of the core layer, width of the core layer unit cell, thickness of the Y-shaped web, and the angle between the Y-shaped branches and the horizontal plane; the material parameters include the density and yield strength of the upper and lower panels, the density and yield strength of the Y-shaped web, the density of the metal foam, the stress of the metal foam platform, and the densification strain of the metal foam; the boundary condition is a fully fixed boundary, and the explosive load is equivalent to a uniformly distributed short-time impulse.

3. The method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure according to claim 1, characterized in that, Calculating the cross-sectional area of ​​the Y-shaped web, the area fraction of the Y-shaped web in the core cell, and the equivalent density of the core layer includes: determining the cross-sectional area of ​​the Y-shaped web in the core cell based on the Y-shaped web thickness, the core cell width, the core half-thickness, and the angle between the Y-shaped branches and the horizontal plane; determining the area fraction based on the ratio of the cross-sectional area to the total cross-sectional area of ​​the core cell; and determining the equivalent density of the core layer based on the area fraction, the Y-shaped web density, and the metal foam density.

4. The method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure according to claim 1, characterized in that, Equivalent of the explosion impulse per unit area to the initial uniform distribution velocity of the upper panel includes dividing the explosion impulse per unit area by the mass per unit area of ​​the upper panel to obtain the initial uniform distribution velocity of the upper panel. The common velocity is calculated by dividing the explosive impulse per unit area by the total mass per unit area of ​​the upper panel, lower panel, and core layer.

5. The method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure according to claim 1, characterized in that, Calculating the normal compressive strength of the core layer includes: determining the plastic compressive strength contribution of the Y-shaped web based on the angle range of the angle between the Y-shaped branch and the horizontal plane; and superimposing the plastic compressive strength contribution of the Y-shaped web with the stress contribution of the metal foam platform determined by the stress of the metal foam platform and the area ratio of the metal foam to obtain the normal compressive strength of the core layer.

6. The method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure according to claim 1, characterized in that, The calculation of the average compressive strain of the core layer includes: determining the dimensionless impulse based on the explosion impulse per unit area, the overall mass per unit area, and the material parameters of the upper and lower panels; determining the mass ratio based on the equivalent density of the core layer, the half-thickness of the core layer, and the mass per unit area of ​​the upper panel; calculating the average compressive strain of the core layer based on the dimensionless impulse, the mass ratio, the half-thickness of the core layer, and the normal compressive strength of the core layer; and taking the average compressive strain of the core layer as the densification strain of the metal foam when the average compressive strain of the core layer is greater than the densification strain of the metal foam.

7. The method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure according to claim 1, characterized in that, Determining the critical impulse for core densification includes: setting the average compressive strain of the core layer equal to the densification strain of the metal foam, and back-calculating the dimensionless critical impulse when the core layer reaches the densification state; comparing the actual dimensionless impulse with the dimensionless critical impulse to determine whether the structure to be predicted will undergo core densification under a given explosive impact.

8. The method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure according to claim 1, characterized in that, The calculation of maximum central deflection and structural response time includes: determining the panel size parameters and plastic hinge folding angle based on the half-length and half-width of the structure; calculating the fully plastic axial force and fully plastic bending moment based on the geometric and material parameters of the Y-shaped section filled with metal foam; determining the section yield trajectory based on the fully plastic axial force and the fully plastic bending moment, or using the membrane force dominant approximation, calculating the dimensionless maximum central deflection and dimensionless response time, and converting them into dimensional maximum central deflection and dimensional structural response time.

9. The method for predicting the explosion impact response of a metal foam-filled Y-shaped sandwich structure according to claim 1, characterized in that, It also includes finite element verification of the prediction results: establishing a finite element model consistent with the input parameters, setting the upper and lower panels and the Y-shaped web as shell elements, setting the metal foam as a three-dimensional solid element, setting binding constraints between the upper and lower panels, the Y-shaped web and the metal foam, and applying the initial uniform velocity of the upper panel to the upper panel; extracting the velocity time history, core layer compression, center deflection time history and maximum center deflection, and comparing them with the prediction results. When the deviation exceeds a preset threshold, the stress of the metal foam platform, the densification strain of the metal foam, the yield strength of the Y-shaped web or the cross-sectional yield trajectory parameters are corrected and then re-predicted.

10. A prediction system for the explosion impact response of a metal foam-filled Y-shaped sandwich structure, characterized in that, include: The parameter acquisition module is used to acquire the geometric parameters, material parameters, boundary conditions and explosion impulse per unit area of ​​the structure to be predicted. The structure to be predicted includes an upper panel, a lower panel, a Y-shaped web and a metal foam filled in the core cavity between the Y-shaped webs. The core layer equivalent parameter calculation module is used to calculate the cross-sectional area of ​​the Y-shaped web, the area fraction of the Y-shaped web in the core layer unit cell, and the core layer equivalent density based on the geometric parameters. The velocity calculation module is used to convert the explosive impulse per unit area into the initial uniform velocity of the upper panel, and to calculate the common velocity of the upper panel, lower panel and core layer at the end of core layer compression based on the conservation of momentum. The compressive strength calculation module is used to calculate the normal compressive strength of the core layer based on the plastic compressive strength contribution of the Y-shaped web and the stress contribution of the metal foam platform. The densification judgment module is used to calculate the average compressive strain of the core layer based on the relationship that the kinetic energy lost during the core layer compression stage is equal to the energy consumed by the plastic compression of the core layer, and to judge whether the core layer is densified based on the comparison result of the average compressive strain of the core layer and the densification strain of the metal foam. The critical impulse calculation module is used to determine the critical impulse of the core layer densification under the condition that the average compressive strain of the core layer is equal to the densification strain of the metal foam. The overall response calculation module is used to calculate the maximum central deflection and structural response time after the core layer compression is completed, based on the finite deflection rigid-plastic theory of fully fixed sandwich panels, combined with the plastic hinge displacement field and the cross-sectional yield trajectory or membrane force dominant approximation of the Y-shaped section filled with metal foam. The result output module is used to output the average compressive strain of the core layer, the critical impulse for core layer densification, the maximum central deflection, and the structural response time.

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