Prediction method and system for implosion dynamic response in a cabin model considering similar distortion effects

Abstract

The present invention belongs to the field of in-cabin explosion prediction, and specifically discloses a method and system for predicting the dynamic response of an implosion in a cabin model considering the similar distortion effect, which includes the steps of: obtaining the relationship between the reflected specific impulse of the plate thickness distortion model and the plate thickness scaling ratio based on the relationship between the deformation energy of the cabin wall structure and the plate thickness; and then determining the relationship between the charge amount of the plate thickness distortion model and the plate thickness scaling ratio according to the relationship between the reflected specific impulse and the charge amount, so as to correct the charge amount of the plate thickness distortion model; performing an implosion test according to the corrected charge amount of the plate thickness distortion model, and thus realizing the prediction of the dynamic response of the cabin prototype according to the dynamic response of the plate thickness distortion model. The present invention proposes a feasible charge correction method for implosion tests in view of the plate thickness distortion phenomenon existing in existing similar scaled models, enabling the consideration of the model production cost, welding quality, and thin plate thickness specification dimensions during the model implosion test, and achieving the test effect of accurately predicting the dynamic response of the prototype.

Description

Technical Field

[0001] The present invention belongs to the field of in-cabin explosion prediction, and more specifically, relates to a method and system for predicting the implosion dynamic response in a cabin model considering similar distortion effects. Background Art

[0002] Modern anti-ship missiles increasingly adopt semi-armor-piercing warheads, which penetrate into the interior of the ship's cabin and explode to maximize the damage power of the warhead. When the semi-armor-piercing missile warhead explodes inside the cabin, due to the closed environment effect of the cabin, the shock wave formed by the explosion will pulsate and converge multiple times inside the structure. At the same time, the quasi-static air pressure load formed by the implosion will also cause serious damage to the cabin structure. Compared with the open environment, the combined action of the implosion shock wave and the quasi-static air pressure in the cabin will cause more serious damage to the cabin wall structure. And improving the anti-implosion performance of the cabin wall can enhance the protection of key cabins of the target. Therefore, the damage of the in-cabin explosion pressure load (including shock wave load and quasi-static air pressure load) to the ship structure is a key concern in the field of ship protection.

[0003] Due to the complexity of the in-cabin explosion problem, although numerical simulation analysis can be carried out through finite element software (such as LS-DYNA, Dytran, Autodyn, etc.) at present, to determine whether the dynamic response results of the simulation are accurate, conclusions can only be drawn through experimental verification. However, full-scale ship or full-scale model tests are extremely costly and difficult to implement. Therefore, researchers at home and abroad often use geometrically scaled models to conduct in-cabin explosion experiments to simulate full-scale ship or full-scale in-cabin explosion tests, in order to obtain relevant information close to the actual damage effect. In model tests, in order to reduce costs, the scale ratio of the structure is often large. However, due to limitations such as welding technology and the specifications of the thin plate thickness, the structural plate thickness during model production cannot be too small. In order to ensure the welding quality and the availability of thin plates, the actual plate thickness of the model structure often exceeds the theoretical scaled model plate thickness. This phenomenon is called plate thickness distortion, and the corresponding structural model is called a plate thickness distortion model (hereinafter referred to as a distortion model). In the implosion test, for the plate thickness distortion model, the best way to predict the dynamic response of the prototype is to modify the charge amount. Therefore, it is crucial to deterministically give the charge amount correction method for the plate thickness distortion model and then propose a method for predicting the dynamic response of the in-cabin implosion of the cabin model considering plate thickness distortion. At present, for the correction of the implosion charge amount of the plate thickness distortion model, both the exponential correction method and the finite element coefficient prediction method are used, but both methods have great uncertainties and human subjectivities. Patent CN114756962A discloses a design method for a non-linear response similarity distortion scaled model of a ship structure, which can adjust the cross-sectional dimensions of the stiffeners on the scaled model of the stiffened plate. However, this design method does not involve the action of implosion loads, and this method focuses on the scaled design of the static strength of the model, and it is difficult to apply to the scaled design of the dynamic response of the model. Patent CN113030179A discloses an equivalent scaled test method for internal explosion of a box-shaped structure, which considers the influence of structural size effect and material strain rate, but does not consider the case of plate thickness distortion. Patent CN113654925A discloses a method for constructing a scaled model of a ship cabin explosion of an anti-ship missile warhead, which also does not involve the construction of a scaled model of a ship cabin explosion in the case of plate thickness distortion. Summary of the Invention

[0004] In view of the above defects or improvement requirements of the prior art, the present invention provides a method and system for predicting the dynamic response of an in-cabin implosion of a cabin model considering similarity distortion effects. The purpose is to propose a feasible charge amount correction method for implosion tests for the plate thickness distortion phenomenon existing in the existing similarity scaled model design process, so that the model production cost, welding quality, and thin plate thickness specifications can be taken into account during the model implosion test, and the test effect of accurately predicting the dynamic response of the prototype can be achieved.

[0005] To achieve the above object, according to one aspect of the present invention, a method for predicting the dynamic response of an in-cabin implosion of a cabin model considering similarity distortion effects is proposed, including the following steps:

[0006] Based on the relationship between the deformation energy of the bulkhead structure and the plate thickness, the relationship between the reflected specific impulse of the plate thickness distortion model and the plate thickness scaling ratio is obtained;

[0007] Furthermore, according to the relationship between the reflected specific impulse and the charge amount, the relationship between the charge amount of the plate thickness distortion model and the plate thickness scaling ratio is determined, so as to correct the charge amount of the plate thickness distortion model;

[0008] An implosion test is carried out according to the corrected charge amount of the plate thickness distortion model, so as to realize the prediction of the dynamic response of the chamber prototype according to the dynamic response of the plate thickness distortion model.

[0009] As a further preference, the relationship between the reflected specific impulse of the plate thickness distortion model and the plate thickness scaling ratio is specifically:

[0010]

[0011] Among them, are the reflected specific impulses of the plate thickness distortion model and the completely similar model respectively, and β and α are the plate thickness scaling ratios of the plate thickness distortion model and the completely similar model respectively.

[0012] As a further preference, the relationship between the reflected specific impulses of the plate thickness distortion model and the completely similar model is:

[0013]

[0014] The deformation energy of the bulkhead structure is approximately proportional to the plate thickness, then there is:

[0015]

[0016] Furthermore, the relationship between the reflected specific impulse of the plate thickness distortion model and the plate thickness scaling ratio is obtained;

[0017] Among them, are the total structural deformation energies of the plate thickness distortion model and the completely similar model respectively, and h dm and h cm are the structural plate thicknesses of the plate thickness distortion model and the completely similar model respectively.

[0018] As a further preference, the calculation formula of the reflected specific impulse I r is:

[0019]

[0020] Among them, p1 is the peak value of the reflected shock wave overpressure, t1 is the positive pressure action time of the shock wave overpressure, p2 is the pressure value of the quasi-static air pressure load, and t2 is the effective action time of the quasi-static air pressure load.

[0021] As a further preference, the relevant parameters in the calculation formula of the reflection specific impulse are specifically as follows:

[0022]

[0023] p2 = 1.3(ω / V)

[0024]

[0025]

[0026] where ω is the charge amount, p0 is the ambient atmospheric pressure, Δp m is the peak overpressure of the incident blast shock wave, V is the internal space volume of the cabin, is the scaled distance, λ sa is a dimensionless coefficient, with a value range of 16.0 to 17.5, L and B are the length and width of the plate, ρ is the mass density of the plate, and σ is the yield strength;

[0027] Then, substituting the reflection specific impulse of the plate thickness distortion model into I r , the charge amount of the plate thickness distortion model can be corrected.

[0028] As a further preference, this dynamic response prediction is applicable to the cases where the bulkhead is a smooth plate, a ribbed plate, or an I-shaped metal sandwich structure.

[0029] As a further preference, an implosion test is conducted according to the charge amount of the modified plate thickness distortion model to make the dynamic response of the plate thickness distortion model similar to the dynamic response of the prototype, so as to predict the deformation deflection h dm of the prototype through the deformation deflection δ p of the plate thickness distortion model, that is: δ p = δ dm / α, where α is the plate thickness scaling ratio of the fully similar model, to achieve the prediction of the dynamic response of the cabin prototype.

[0030] According to another aspect of the present invention, there is provided a prediction system for the dynamic response of an implosion of a cabin model considering the similarity distortion effect, which includes a processor for executing the above-mentioned method for predicting the dynamic response of an implosion of a cabin model considering the similarity distortion effect.

[0031] Generally speaking, compared with the prior art by the above technical solutions conceived by the present invention, the following technical advantages are mainly possessed:

[0032] 1. The present invention derives the relationship between the reflected specific impulse and the scaling ratio of the structural plate thickness based on the relationship between the structural deformation energy and the structural plate thickness, and then obtains the relationship between the specific impulse and the charge amount according to the theoretical calculation formula of the specific impulse, realizing the charge correction of the implosion test, so that the model production cost, welding quality and thin plate thickness specification dimensions can be taken into account during the model implosion test, and the accuracy of the prototype dynamic response prediction can be improved.

[0033] 2. The present invention studies various structures of the bulkhead and finds that the structural deformation energy of the bulkhead and the plate thickness are approximately in a direct proportion relationship. Based on this, the relationship between the plate thickness scaling ratio and the charge amount is established; this method is mainly used for the charge correction of the plate thickness distortion model in the implosion scale model test of the ship cabin, and can be used as a reference for the implosion scale model test in other protection fields. Description of the Drawings

[0034] Figure 1 Schematic diagram of the bare plate (flat plate) structure of the embodiment of the present invention;

[0035] Figure 2 Schematic diagram of the deformation mode of the bare plate (flat plate) of the embodiment of the present invention, where (a) is the overall large deformation and (b) is the local deformation;

[0036] Figure 3 Schematic diagram of the stiffened plate (reinforced plate) structure of the embodiment of the present invention;

[0037] Figure 4 Among them, (a)-(c) are schematic diagrams of three deformation modes of the stiffened plate (reinforced plate) of the embodiment of the present invention;

[0038] Figure 5 Schematic diagram of the I-shaped metal sandwich structure of the embodiment of the present invention;

[0039] Figure 6 Among them, (a)-(c) are schematic diagrams of three deformation modes of the I-shaped metal sandwich structure of the embodiment of the present invention;

[0040] Figure 7 Among them, (a) and (b) are the implosion load models before and after simplification of the embodiment of the present invention;

[0041] Figure 8 Flow chart of the similar prediction of the implosion dynamic response of the cabin structure of the embodiment of the present invention;

[0042] Figure 9 Schematic diagram of the bare plate (flat plate) bulkhead cabin of the embodiment of the present invention;

[0043] Figure 10Displacement nephograms of four models of the bulkhead cabin of the light board (flat board) according to the embodiments of the present invention. Among them, (a) is the prototype, (b) is the fully similar scaled-down model, (c) is the plate thickness distortion model without corrected charge, and (d) is the plate thickness distortion model with corrected charge;

[0044] Figure 11 Schematic diagram of the bulkhead cabin with stiffened plates (reinforced plates) according to the embodiments of the present invention;

[0045] Figure 12 Displacement nephograms of four models of the bulkhead cabin with stiffened plates (reinforced plates) according to the embodiments of the present invention. Among them, (a) is the prototype, (b) is the fully similar scaled-down model, (c) is the plate thickness distortion model without corrected charge, and (d) is the plate thickness distortion model with corrected charge;

[0046] Figure 13 Schematic diagram of the cabin with I-type metal sandwich structure according to the embodiments of the present invention;

[0047] Figure 14 Displacement nephograms of four models of the bulkhead cabin with I-type metal sandwich structure according to the embodiments of the present invention. Among them, (a) is the prototype, (b) is the fully similar scaled-down model, (c) is the plate thickness distortion model without corrected charge, and (d) is the plate thickness distortion model with corrected charge. Detailed implementation manners

[0048] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0049] A method for predicting the dynamic response of the implosion of a cabin model considering the similarity distortion effect provided by the embodiments of the present invention is mainly a method for predicting the dynamic response of a prototype under the action of an in-cabin explosion pressure load (including a shock wave load and a quasi-static air pressure load) for a light board (i.e., a flat board), a stiffened board (i.e., a reinforced board), and an I-type metal sandwich structure plate thickness distortion model.

[0050] The present invention analyzes various structures of the bulkhead, determines that the structural deformation energy and the plate thickness are approximately proportional to each other; then, based on the relationship between the structural deformation energy and the structural plate thickness, the relationship between the implosion specific impulse and the scale ratio of the structural plate thickness is deduced, and then according to the theoretical calculation formula of the specific impulse, the relationship between the specific impulse and the charge amount is obtained. By combining these two relationships, the corrected relationship between the charge amount and the scale ratio of the plate thickness is given, so that the dynamic response of the prototype can be accurately predicted by using the dynamic response of the plate thickness distortion model.

[0051] Specifically, it includes the following steps:

[0052] 1. Calculation of the deformation energy of the light plate (flat plate) structure

[0053] The length of the light plate (flat plate) studied in this invention is L, the width is B, and the plate thickness is h, as Figure 1 shown. Under the action of the implosion load, the light plate (flat plate) has two deformation modes: overall large deformation and local deformation, as Figure 2 shown.

[0054] In the overall large deformation mode, the deformation energy of the light plate (flat plate) mainly includes the bending deformation energy (i.e., the bending strain potential energy) U a and the film tensile deformation energy (i.e., the mid-surface tensile strain potential energy) U b .

[0055] For the bending deformation energy, according to the bending deformation relationship, that is, the strain satisfies:

[0056]

[0057] where δ is the displacement of any point in the stiffened plate, Z is the z coordinate of this point; ε x , ε y , γ xy , γ yx are the strain components of this point.

[0058] Introducing the assumption of rigid-plastic material, when yielding occurs:

[0059] σ x =σ s , σ y =σ s (2) According to the Von-Mises yield criterion, there is

[0060]

[0061] where σ s is the material yield limit, σ x , σ y , τ xy , τ yx are the stress components of this point.

[0062] Therefore, the bending deformation energy is

[0063]

[0064] The mid-surface strain caused by the displacement is:

[0065]

[0066] The film tensile deformation energy is:

[0067] U b =∫∫(Nx ε x +N y ε y +2N xy γ xy )dxdy (6)

[0068] Among them, N x , N y , N xy is the mid-plane stress,

[0069] N x = hσ x , N y = hσ y , N xy = hτ xy (7)

[0070] Therefore, there is

[0071]

[0072] Assume that the deformation deflection function of the light plate (flat plate) is:

[0073]

[0074] Substituting the deflection function, the deformation energy U of the light plate (flat plate) under the overall large deformation mode can be obtained total as:

[0075]

[0076] In the case of overall large deformation, the deformation deflection of the light plate (flat plate) is much larger than the plate thickness. Therefore, it can be approximately considered that the deformation energy of the light plate (flat plate) is proportional to the plate thickness:

[0077]

[0078] U total ∝ h (12)

[0079] In the local deformation mode, the deformation energy of the light plate (flat plate) still mainly includes the bending deformation energy (i.e., bending strain potential energy) U a and the film tensile deformation energy (i.e., mid-plane tensile strain potential energy) U b . The calculation formula can still adopt Equations (1)-(8). However, since the range of local deformation is not the entire plate but a local area within a certain range, when assuming the deformation deflection function, the length L and width B of the plate in Equation (9) need to be replaced by the length and width of the actual deformation range.

[0080] In the case of local deformation, the deflection of the light plate (flat plate) is still much larger than the plate thickness. Therefore, it can be approximately considered that the deformation energy of the light plate (flat plate) is still proportional to the plate thickness at this time. Thus, the relationship formula (12) can still be obtained.

[0081] 2. Calculation of the deformation energy of the stiffened plate (reinforced plate) structure

[0082] The panel of the stiffened plate (reinforced plate) studied in this invention has a length of L, a width of B, and a plate thickness of h f ; the thickness of the stiffener is h c , the height is H, the spacing is l, as Figure 3 shown. Under the action of the implosion load, there are three deformation modes for the stiffened plate (reinforced plate), as Figure 4 shown.

[0083] For the panel of the stiffened plate (reinforced plate), its deformation energy can be calculated according to the calculation method of the deformation energy of the light plate (flat plate) structure. It can be obtained that under the three deformation modes, the deformation energy U f of the panel of the stiffened plate (reinforced plate) is proportional to its plate thickness h f , that is

[0084] U f ∝h f (13)

[0085] For the stiffener of the stiffened plate (reinforced plate), if the position of the stiffener is x i , and the distribution of the stiffener is symmetric about the y-axis. Assuming that the deformation of the stiffener is the same as that of the panel, the same deflection function can be adopted:

[0086]

[0087] Then the structural deformation energy of this stiffener is:

[0088]

[0089] The size of the stiffener is H×h c , because

[0090] M s =(h c H 2 / 4)σ s , θ(y)=d 2 δ / dy 2 (16)

[0091] Then the deformation energy of this stiffener is:

[0092]

[0093] For (L / l) stiffeners, the total deformation energy is:

[0094]

[0095] Thus, the strain energy U of the stiffened plate (ribbed plate) c is proportional to the thickness h of the stiffened plate c as follows:

[0096] U c ∝h c (19)

[0097] The total structural strain energy of the stiffened plate (ribbed plate) includes the strain energy of the faceplate and the strain energy of the stiffeners, i.e.,

[0098] U total =(U f +U c ) (20)

[0099] Therefore, the total structural strain energy of the stiffened plate (ribbed plate) is proportional to the thicknesses of the faceplate and the stiffeners, i.e.,

[0100] U total ∝(h f ,h c ) (21)

[0101] For a stiffened plate (ribbed plate) with cross or intersecting stiffeners, it can still be concluded that the total structural strain energy of the stiffened plate (ribbed plate) is proportional to the thicknesses of the faceplate and the stiffeners, and still conforms to the relationship (21).

[0102] 3. Calculation of the strain energy of the I-shaped metal sandwich structure

[0103] For the I-shaped sandwich structure studied in the present invention (see Figure 5 ), the lengths of the upper and lower faceplates are L, the widths are B, the thickness of the upper faceplate is h f , the thickness of the lower faceplate is h b , the height of the I-shaped sandwich is H, the plate thickness is h c , and the spacing of the I-shaped sandwich is l.

[0104] Under the action of the in-cabin explosion load, there are mainly three deformation modes of the I-shaped metal sandwich structure: Deformation mode I is the overall large deformation of the upper and lower faceplates and the sandwich; Deformation mode II is the obvious local deformation of the front plate and the overall large deformation of the rear plate; Deformation mode III is the obvious local deformation of both the front plate and the rear plate, as Figure 6 shown.

[0105] For the upper and lower faceplates of the I-shaped metal sandwich structure, their strain energies can be calculated according to the calculation method of the strain energy of the plain plate (flat plate) structure. It can be obtained that under the three deformation modes, the strain energies U f 、U b of the upper and lower faceplates of the I-shaped metal sandwich structure are respectively proportional to the plate thickness hf , h b is directly proportional to, that is

[0106] U f ∝ h f (22)

[0107] U b ∝ h b (23)

[0108] For the core of the type-I metal sandwich structure, its deformation energy can be calculated according to the structural deformation calculation method of the stiffened plate (ribbed plate) structure in the calculation of the deformation energy of the stiffened structure. It can be obtained that under the three deformation modes, the deformation energy U of the core of the type-I metal sandwich structure c is directly proportional to the core plate thickness h c that is

[0109] U c ∝ h c (24)

[0110] The total deformation energy of the type-I metal sandwich structure is equal to the sum of the deformation energies of the upper panel, the lower panel and the core, that is

[0111] U total = U f + U b + U c (25)

[0112] In summary, the following relationship is satisfied between the total deformation energy of the type-I metal sandwich structure and the plate thicknesses of each component:

[0113] U total ∝ (h f , h b , h c ) (26)

[0114] Through the analysis of various structures in the above 1-3, it can be determined that the structural deformation energy and the plate thickness are approximately in a direct proportional relationship.

[0115] 4. Calculation of the reflected specific impulse of the implosion load

[0116] The simplified load models of the in-cabin explosion shock wave load and the quasi-static pressure load are as Figure 7 shown.

[0117] There are four key parameters in the simplified load model, namely the peak overpressure p1 of the reflected shock wave, the positive pressure action time t1 of the shock wave overpressure, the pressure value p2 of the quasi-static air pressure load, and the effective action time t2 of the quasi-static air pressure load.

[0118]

[0119]

[0120]

[0121] Among them, ω is the charge amount, with the unit of kg; R is the straight-line distance from the explosion center of the TNT charge to the target measurement position, with the unit of m; p0 is the ambient atmospheric pressure, which is 0.101 MPa; Δp m is the peak value of the incident overpressure of the explosion shock wave, with the unit of MPa; is the scaled distance.

[0122] The positive pressure action time of the shock wave overpressure is:

[0123]

[0124] The pressure value of the quasi-static air pressure load is:

[0125] p2 = 1.3(ω / V) (MPa) (31)

[0126] Among them, V is the internal space volume of the cabin, with the unit of m 3 .

[0127] The effective action time of the quasi-static air pressure load is:

[0128]

[0129] Among them, λ is a dimensionless coefficient, and its value range is 16.0 - 17.5; L and B are the side lengths of the rectangular plate, with the unit of m; ρ is the mass density of the plate, with the unit of g / m 3 ; σ is the yield strength, with the unit of MPa.

[0130] Therefore, the reflected specific impulse I r of the implosion load is:

[0131]

[0132] Under the condition that the scaled explosion distance, material, and model size remain unchanged, the conversion relationship between the total reflected specific impulse of the cabin target wall subjected to the internal explosion load and the charge amount is calculated by formulas (27) - (33).

[0133] 5. Charge correction of the geometric distortion model

[0134] The spatial scale ratios of the length and width of the structure involved in the present invention are both α. For a completely similar model, the plate thickness scale ratio is α; for a plate thickness distortion model, the plate thickness scale ratio is β. The following is to correct the reflected specific impulse I r of the implosion load, so as to accurately predict the dynamic response of the prototype by using the dynamic response of the plate thickness distortion model. The reflected specific impulse Ir Ultimately, it is reflected in the correction of the charge amount, and the correction process is as follows:

[0135] Define the correction equation:

[0136] λ I = μλ h (34)

[0137] where μ is the correction factor, and λ h = α / β.

[0138] According to the momentum theorem, we have:

[0139] I r = mv (35)

[0140] where m is the mass per unit area of the structure, and v is the velocity obtained by the structure.

[0141] Under the action of the implosion load, the kinetic energy E obtained by the structure k is:

[0142]

[0143] where M is the total mass of the cabin bulkhead structure.

[0144] During the deformation process after the bulkhead structure obtains kinetic energy, without considering energy loss, the kinetic energy of the structure is all converted into structural deformation energy. Then, the specific impulse relationship between the plate thickness distortion model and the fully similar model of the bulkhead structure is:

[0145]

[0146] In the formula, U total represents the structural deformation energy, h represents the plate thickness, the superscript dm represents the plate thickness distortion model, and the superscript cm represents the fully similar model.

[0147] Also, since the structural deformation energy is approximately proportional to the plate thickness, then:

[0148]

[0149] Therefore, we have

[0150]

[0151] It can be obtained that:

[0152]

[0153] After obtaining the reflection specific impulse relationship formula (40) between the distortion model and the fully similar model, then according to the relationship formulas (27) - (33) between the specific impulse and the charge amount, the corrected charge amount of the distortion model is inversely deduced.

[0154] 6. Prediction of Prototype Dynamic Response under Implosion Load

[0155] Under the action of the implosion load, the process of predicting the prototype dynamic response using the plate thickness distortion model is as Figure 8 shown. Among them, the charge amount ω dm is corrected through the relational expression (40). The basic idea of the dynamic response prediction is: by correcting the charge amount of the plate thickness distortion model, making the dynamic response of the plate thickness distortion model similar to that of the prototype dynamic response, so as to predict the deformation deflection δ dm of the prototype through the deformation deflection δ p of the plate thickness distortion model, that is

[0156] δ p = δ dm / α (41)

[0157] The following are specific embodiments:

[0158] Embodiment 1

[0159] Refer to Figure 9 the bare plate (flat plate) bulkhead compartment, and conduct numerical simulation calculations on the prototype, the fully similar scaled model, the plate thickness distortion model with uncorrected charge amount, and the plate thickness distortion model with corrected charge amount.

[0160] The ratio of the dimensions of the bare plate (flat plate) bulkhead compartment of the fully similar scaled model to those of the prototype compartment is 1:4, and the ratio of the plate thicknesses is 1:4; the ratio of the dimensions of the plate thickness distortion model (including uncorrected and corrected charge amounts) to those of the prototype compartment is 1:4, and the ratio of the plate thicknesses is 1:2. The implosion charge amounts in each model compartment are shown in Table 1 below.

[0161] Table 1 Implosion Charge Amounts in the Bare Plate (Flat Plate) Bulkhead Compartment Model

[0162]

[0163] Through numerical simulation calculations, the displacement nephograms of the four models of the bare plate (flat plate) bulkhead compartment are as Figure 10 shown. The deformation modes and deformation regions of the target compartments of the four models are basically the same, and they are all large deformations of the entire bare plate (flat plate) bulkhead.

[0164] The comparison of the final deflection values of the central points of the target bulkheads of the four models of the bare plate bulkhead compartment is shown in Table 2.

[0165] Table 2 Comparison of the Final Deflection Values of the Target Bulkheads of the Four Models of the Bare Plate (Flat Plate) Bulkhead Compartment

[0166]

[0167] The deflection prediction value of the bare (flat) bulkhead cabin plate thickness distortion model after charge correction and the actual deflection value of the prototype are reduced to -15.07%, greatly improving the prediction accuracy of the implosion dynamic response in the bare (flat) bulkhead cabin model.

[0168] Example 2

[0169] See Figure 11 For the stiffened plate (ribbed plate) bulkhead cabin in

[0170] The size ratio of the stiffened plate (ribbed plate) bulkhead cabin of the fully similar scaled model to the prototype cabin is 1:4, and the plate thickness ratio is 1:4; the size ratio of the plate thickness distortion model (including uncorrected and corrected charges) to the prototype cabin is 1:4, and the plate thickness ratio is 1:2. The implosion charges in each model cabin are shown in Table 3 below.

[0171] Table 3 Implosion Charges in the Stiffened Plate (Ribbed Plate) Bulkhead Cabin Model

[0172]

[0173] Through numerical simulation calculations, the displacement nephograms of the four models of the stiffened plate (ribbed plate) bulkhead cabin are as Figure 12 shown. The deformation modes and deformation regions of the target cabins of the four models are basically the same, all being the overall large deformation of the stiffened plate (ribbed plate) bulkhead. The comparison of the final deflection values at the center points of the target bulkheads of the four models of the stiffened plate (ribbed plate) bulkhead cabin is shown in Table 4.

[0174] Table 4 Comparison of the Final Deflection Values of the Target Bulkheads of the Four Models of the Stiffened Plate (Ribbed Plate) Bulkhead Cabin

[0175]

[0176] The error between the deflection prediction value of the stiffened plate (ribbed plate) bulkhead cabin plate thickness distortion model after charge correction and the actual deflection value of the prototype is reduced to 5.73%, greatly improving the prediction accuracy of the implosion dynamic response in the stiffened plate (ribbed plate) bulkhead cabin model.

[0177] Example 3

[0178] See Figure 13 For the I-shaped metal sandwich structure bulkhead cabin in

[0179] The size ratio of the fully similar scaled model of the I-type metal sandwich structure bulkhead compartment to the prototype compartment is 1:4, and the plate thickness ratio is 1:4; the size ratio of the plate thickness distortion model (including uncorrected and corrected charges) to the prototype compartment is 1:4, and the plate thickness ratio is 1:2. The internal explosion charges of each model compartment are shown in Table 5 below.

[0180] Table 5 Internal explosion charges of the I-type metal sandwich structure bulkhead compartment model

[0181]

[0182] Through numerical simulation calculations, the displacement nephograms of the four models of the I-type metal sandwich structure bulkhead compartment are as Figure 14 shown. The deformation modes and deformation regions of the target compartments of the four models are basically the same, all being the overall large deformation of the I-type metal sandwich structure bulkhead. The final deflection values of the central points of the target bulkheads of the four models of the I-type metal sandwich structure bulkhead compartment are shown in Table 6.

[0183] Table 6 Comparison of the final deflection values of the target bulkheads of the four models of the I-type metal sandwich structure bulkhead compartment

[0184]

[0185] The error between the predicted deflection value of the plate thickness distortion model of the I-type metal sandwich structure bulkhead compartment after charge correction and the actual deflection value of the prototype is reduced to 2.95%, greatly improving the prediction accuracy of the internal explosion dynamic response of the I-type metal sandwich structure bulkhead compartment model.

[0186] It is easy for those skilled in the art to understand that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for predicting the dynamic response of the implosion of a cabin model considering the similar distortion effect, characterized in that It includes the following steps: Based on the relationship between the deformation energy of the bulkhead structure and the plate thickness, obtain the relationship between the reflected specific impulse of the plate thickness distortion model and the plate thickness scaling ratio; Furthermore, according to the relationship between the reflected specific impulse and the charge amount, determine the relationship between the charge amount of the plate thickness distortion model and the plate thickness scaling ratio, so as to correct the charge amount of the plate thickness distortion model; Reflectance impulse I r The calculation formula is as follows: Wherein, p1 is the peak overpressure of the reflected shock wave, t1 is the positive pressure action time of the shock wave overpressure, p2 is the pressure value of the quasi-static air pressure load, and t2 is the effective action time of the quasi-static air pressure load. The calculation formula is as follows: p2 = 1.3(ω / V) where ω is the charge amount, p0 is the ambient atmospheric pressure, and Δp m is the peak overpressure of the incident blast shock wave, V is the internal space volume of the chamber, is the scaled distance, and λ sa is a dimensionless coefficient with a value range of 16.0 - 17.5, L and B are the length and width of the plate, ρ is the mass density of the plate, and σ is the yield strength; Then, the reflected specific impulse of the plate thickness distortion model is substituted into I r , and the charge amount of the plate thickness distortion model is corrected; Carry out an implosion test according to the charge amount of the corrected plate thickness distortion model, so as to predict the dynamic response of the cabin prototype based on the dynamic response of the plate thickness distortion model.

2. The method for predicting the implosion dynamic response in a chamber model considering the similar distortion effect as claimed in claim 1, wherein The relationship between the reflected specific impulse of the plate thickness distortion model and the plate thickness scaling ratio is specifically: Among them, are the reflected specific impulse of the plate thickness distortion model and the complete similarity model respectively, and β and α are the plate thickness scaling ratios of the plate thickness distortion model and the complete similarity model respectively.

3. The method for predicting the implosion dynamic response in a chamber model considering similar distortion effects according to claim 2, characterized in that, The relationship between the reflected specific impulse of the plate thickness distortion model and the completely similar model is: The deformation energy of the bulkhead structure is approximately proportional to the plate thickness, then there is: Furthermore, obtain the relationship between the reflected specific impulse of the plate thickness distortion model and the plate thickness scaling ratio; Among them, are the total structural deformation energies of the plate thickness distortion model and the completely similar model, respectively, and h dm , h cm are the structural plate thicknesses of the plate thickness distortion model and the completely similar model, respectively.

4. The method for predicting the implosion dynamic response in a chamber model considering the similar distortion effect as claimed in claim 1, characterized in that, This dynamic response prediction is applicable to the cases where the bulkhead is a smooth plate, a ribbed plate, or an I-shaped metal sandwich structure.

5. The method for predicting the implosion dynamic response in a chamber model considering similar distortion effects according to any one of claims 1-4, characterized in that, The charge amount is determined according to the modified plate thickness distortion model for the implosion test, making the dynamic response of the plate thickness distortion model similar to that of the prototype, so as to predict the deformation deflection δ of the prototype through the deformation deflection δ of the plate thickness distortion model dm That is, predict the deformation deflection δ of the prototype p , namely: δ p = δ dm / α, where α is the plate thickness scaling ratio of the fully similar model, to achieve the prediction of the dynamic response of the cabin prototype 6. A prediction system for the implosion dynamic response in a cabin model considering similar distortion effects, characterized in that, It includes a processor, and the processor is used to execute the implosion dynamic response prediction method of the cabin model considering the similar distortion effect according to any one of claims 1-5.

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