Method for evaluating damage performance of warship under multiple impact load

Abstract

The application discloses a kind of multiple impact load under the warship damage performance evaluation method, it includes: dividing warship first damage grade, obtains the warship damage parameter threshold under different first damage grade by theoretical calculation or simulation analysis;Measured under the first impact load the damage parameter of warship;Introduce attenuation coefficient, calculate the damage parameter of warship under multiple impact load;The final damage parameter obtained by calculation and damage parameter threshold are compared, determine damage coefficient, and assess damage grade.The application considers the attenuation of material strength under multiple impacts, and the damage grade of warship under multiple impact load can be more accurately determined.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of warship damage assessment technology. BACKGROUND

[0002] Damage assessment refers to the physical characteristics of the target ship, according to the comprehensive consideration of the battle purpose, battlefield environment, damage power and other factors, the fire strike effect is comprehensively analyzed, and then according to the damage calculation result of the weapon to the target ship, the damage of the equipment to the system to the whole ship is qualitatively and quantitatively evaluated. The target damage effect evaluation is carried out quickly and accurately, which can not only optimize the fire power, but also improve the utilization efficiency of combat resources. If the damage effect analysis of the target is insufficient, and the vulnerability, damage criterion and damage effect of the target are not studied deeply, the warhead damage element design may be poor, and the actual damage resistance performance of the ship is poor. Therefore, it is necessary to evaluate the damage level of the target according to the damage under different combat waves, fully exert the efficient damage capacity, improve the combat planning level, and guide the actual combat.

[0003] At present, the domestic damage evaluation method of surface ship is mainly the evaluation under single impact load, which cannot accurately evaluate the damage level and damage effect of warship under multiple impact loads. SUMMARY

[0004] The present application provides a method for accurately evaluating the damage performance of warship under multiple impact loads.

[0005] The technical scheme of the present application is as follows:

[0006] A method for evaluating the damage performance of warship under multiple impact loads, comprising:

[0007] S1: dividing the first damage level of the warship according to the damage degree of the structure of the warship, and obtaining the damage parameter threshold of the warship on water and underwater under different first damage levels through simulation experiment and / or simulation model calculation; the damage parameter threshold includes the threshold of the maximum deformation deflection ω of the warship shell after impact load compared with before impact, and the threshold of the maximum crack width l of the crack generated by the shell after impact load;

[0008] S2: obtaining the damage parameters of the warship material of the warship to be evaluated for damage performance under multiple impact loads through damage parameter determination experiment and calculation based on experimental data, the damage parameters including the maximum deformation deflection ω of the material n And the maximum crack width l n ;

[0009] S3: determining a second damage level and a damage coefficient of the warship to be evaluated according to the comparison between the damage parameter of the obtained warship material and the threshold value of the damage parameter of the warship on water and underwater, and determining the damage performance of the warship according to the damage coefficient, and / or the second damage level and the first damage level;

[0010] wherein the damage parameter is obtained by the following calculation model:

[0011] ω n = f(R n A1), l n = g(R n A1), n≥1,

[0012] wherein, represents the total attenuation coefficient, A1 represents the initial strength of the material, σ s(n) represents the yield strength of the material under the n-th impact load obtained by the damage parameter determination experiment, σ s(l) represents the initial yield strength of the material, f and g represent the functional relationship between the damage parameter and the material strength measured by the damage parameter determination experiment.

[0013] According to some embodiments of the present application, the damage parameter determination experiment comprises:

[0014] A flat warship deck sample is obtained for the experiment, and the sample is impacted by impact loads with the same size and the impact point being the center of the sample, and the maximum deformation deflection and the maximum crack width of the sample before and after the first impact are measured;

[0015] The yield strength and the material strength of the sample after each impact load are measured according to GB / T228.1-200;

[0016] The attenuation coefficient is determined according to the change of the yield strength of the material after each impact load, and the functional relationship between the material strength and the damage parameter is determined according to the change of the material strength.

[0017] According to some embodiments of the present application, the first damage level is divided as follows: the sinking of the warship is the first damage, the complete loss of the combat capability of the warship but not sinking is the second damage, and the combat capability of the warship is reduced but not completely lost is the third damage.

[0018] According to some embodiments of the present application, the damage coefficient λ i is obtained by the following calculation model:

[0019]

[0020] wherein a and b respectively represent on water and underwater, i represents the second damage level, ω jiThreshold value of maximum deformation deflection in the jth case of the ith damage level under the first damage level, l ji Threshold value of maximum crack width in the jth case of the ith damage level under the first damage level.

[0021] According to some embodiments of the present application, the damage coefficient is obtained by the following calculation model:

[0022]

[0023] According to some embodiments of the present application, the second damage level is determined by the following model:

[0024]

[0025] According to some embodiments of the present application, the determining the damage performance of the warship according to the second damage level and the first damage level comprises: taking the most serious damage level between the first damage level and the second damage level of the warship to be evaluated for the damage performance as the evaluation damage level of the warship.

[0026] The present application considers the influence of multiple impact loads on the material strength of the warship, and can more accurately quantitatively evaluate the damage of the warship under multiple impact loads. It can more truly reflect the actual damage state of the warship under multiple impact loads. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The evaluation flowchart of the present application is described in the embodiments.

[0028] Figure 2 The impact load action model involved in the embodiments is shown in the figure.

[0029] Figure 3 The damage parameters (maximum deformation deflection ω and maximum crack width l) involved in the embodiments are shown in the figure.

[0030] Figure 4 The determination experiment flowchart of the damage parameters involved in the embodiments is shown in the figure. EMBODIMENTS

[0031] The present application is described in detail below in combination with embodiments and drawings, but it should be understood that the embodiments and drawings are only used to exemplarily describe the present application, and cannot constitute any limitation on the protection scope of the present application. All reasonable transformations and combinations within the scope of the inventive concept of the present application fall within the protection scope of the present application.

[0032] REFERENCE Figures 1-4According to the technical scheme of the present application, a specific warship damage level evaluation method under multiple impact loads comprises the following steps:

[0033] Step 1: According to the damage degree of the warship structure, the first damage level of the warship is divided, and the damage parameter threshold of the warship on water and underwater under different first damage levels is obtained through simulation experiment and / or simulation model calculation. The damage parameter threshold includes the maximum deformation deflection ω and the maximum crack width l; wherein the maximum deformation deflection refers to the maximum linear displacement of the warship shell after the warship is impacted by the impact load compared with before the impact; the maximum crack width refers to the maximum width of the crack generated by the shell rupture after the warship is impacted by the impact load, as follows:

[0034] ω=(ω a ,ω b ), l=(l a , l b ), a, b represent water and underwater respectively.

[0035] In some specific embodiments, the first damage level is divided into three levels according to the sinking of the warship, the loss of combat capability of the warship but not sinking, and the decline of combat capability of the warship but not losing combat capability.

[0036] More specifically, the division standard is shown in the following Table 1:

[0037] Table 1:

[0038]

[0039]

[0040] Step 2: The damage parameters of the warship material of the target warship to be evaluated for damage performance evaluation under multiple impact loads are obtained through damage parameter determination experiment and calculation based on experimental data, and the damage parameters include the maximum deformation deflection and the maximum crack width of the material.

[0041] Further, referring to the attached Figure 4 In some specific embodiments, the damage parameter determination experiment comprises:

[0042] A flat warship deck sample is obtained for experiment, with the center point of the sample as the origin and the flat surface as the xz plane to establish an experimental coordinate system, and the sample is impacted multiple times by an impact load with a size of F and an acting point of the center point of the sample, i.e. the origin of the experimental coordinate system, and the maximum deformation deflection and the maximum crack width of the sample before and after the first impact are measured;

[0043] The yield strength and material strength of the sample plate after each impact load is determined according to GB / T 228.1-200, and the decay coefficient and the functional relationship between the material strength and the damage parameter are determined according to the change of the yield strength of the material after each impact load.

[0044] It can further include:

[0045] S21 determines the maximum deformation deflection ω1 and the maximum crack width l1 of the ship deck sample under the first impact load according to the damage parameter obtained by the experiment.

[0046] S22: Under the subsequent impact load, the material strength decay coefficient r of the ship deck sample is introduced i , and the maximum deformation deflection and the maximum crack width of the ship material under the decay coefficient are calculated.

[0047] Wherein, the decay coefficient is as follows:

[0048]

[0049] σ s(i) represents the yield strength of the material under the i-th impact load, which is measured according to GB / T 228.1-2010.

[0050] Under the above decay coefficient, the initial ship material strength is A1, and the decay coefficient is r1, then after the second impact, the material strength decays to r1A1, and the obtained maximum deformation deflection and maximum crack width are as follows:

[0051] ω2=f(r1A1),l2=g(r1A1) (7)

[0052] Wherein, the functions f and g are the functions for determining the functional relationship between the damage parameter threshold and the material strength;

[0053] After n impacts (n≥2), the decay coefficient that changes with the number of impacts is r n , then at the n-th impact, the material strength is:

[0054] A n =r n-1 A n-1 (8)

[0055] That is:

[0056]

[0057] Wherein, A1 is the initial strength, that is, the strength at the first impact, and A n is the final strength at the n-th impact load, and the total decay coefficient is recorded as:

[0058]

[0059] The maximum deformation deflection and the maximum crack width after n (n≥2) impacts are as follows:

[0060] ω n = f(R n A1), l n = g(R n A1) (11)

[0061] Let R1=r0=1, ω0=ω1, l0=l1 when n=1,

[0062] Then n≥1

[0063]

[0064] ω n = f(R n A1), l n = g(R n A1), n≥1 (13)

[0065] Step three: according to the comparison of the obtained damage parameters of the ship material and the damage parameter threshold of the ship on water and underwater, the second damage level and damage coefficient of the target ship are determined, and according to the damage coefficient, and / or the second damage level and the first damage level, the damage performance of the ship is determined.

[0066] More specifically, the second damage level is set as follows: according to the three first damage levels of the ship, the parameter threshold is set as ω ai , ω bi ; l ai , l bi (subscript a, b represents the water and underwater part respectively; i=1, 2, 3 is the damage level), according to the comparison of the damage parameters of the ship material and the damage parameter threshold, the damage level under n times impact load is determined as shown in Table 2:

[0067] Table 2

[0068]

[0069]

[0070] Further, the damage system is obtained by the following process:

[0071] The damage coefficient λ i of i level, i=1, 2, 3 represents the damage level, and is defined as follows:

[0072]

[0073] Substituting equations (12) and (13) into formula (14) yields the damage coefficient:

[0074]

[0075] The damage coefficient can be used to quantitatively represent the damage capability of a ship to multiple impact loads. The larger the coefficient, the stronger the damage to the ship subjected to multiple impact loads.

[0076] Furthermore, by combining the damage severity classifications in Tables 1 and 2, the highest damage severity can be selected as the damage severity level of the ship after multiple load impacts. For example, if a ship's material ω... n ≥ω a1 If the damage level is 1, then the second damage level is Level 1 damage to the ship. If the damage level is 2, then the first damage level is Level 2 damage to the ship. The highest damage level is taken as the damage level of the ship, and it is Level 1 damage.

[0077] The above embodiments are merely preferred embodiments of the present invention, and the scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for evaluating the damage performance of a ship under multiple impact load, characterized in that, It comprises: S1: dividing the warship into a first damage level according to the damage degree of the warship structure, and obtaining the damage parameter threshold of the warship on water and underwater under different first damage levels through simulation experiment and / or simulation model calculation; the damage parameter threshold comprises the threshold of the maximum deformation deflection ω of the warship shell after being impacted by the impact load compared with before being impacted, and the threshold of the maximum crack width l of the crack of the warship shell after being impacted by the impact load; S2: obtaining the damage parameters of the warship material of the warship to be evaluated for damage performance under multiple impact loadings through a damage parameter determination experiment and calculation based on experimental data, the damage parameters including the maximum deformation deflection ω of the material n and the maximum crack width l n ; S3: determining the second damage level and the damage coefficient of the warship to be evaluated for damage performance according to the comparison of the damage parameter of the obtained warship material and the damage parameter threshold of the warship on water and underwater, and determining the damage performance of the warship according to the damage coefficient, and / or the second damage level and the first damage level; Wherein, the damage parameter is obtained through the following calculation model: ω n = f(R n A1),l n = g(R n A1),n≥1, wherein, represents the total attenuation coefficient, A1represents the initial strength of the material, σ s(n) represents the yield strength of the material under the n-th impact load obtained by the damage parameter measurement experiment, σ s(1) represents the initial yield strength of the material, f, g represents a functional relationship between the damage parameter and the strength of the material measured by the damage parameter measurement experiment.

2. The method according to claim 1, wherein, The damage parameter determination experiment comprises: A flat warship deck sample is obtained for experiment, the sample is impacted by impact load multiple times with the same size and the impact point being the center of the sample, and the maximum deformation deflection and the maximum crack width of the sample before and after the first impact are measured; The yield strength and the material strength of the sample after each impact load are measured according to GB / T228.1-200; The attenuation coefficient is determined according to the change of the yield strength of the material after each impact load, and the function relationship between the material strength and the damage parameter is determined according to the change of the material strength.

3. The method according to claim 1, wherein, The first damage level is divided as follows: the sinking of the warship is the first damage, the complete loss of the combat capability of the warship but not sinking is the second damage, and the combat capability of the warship is reduced but not completely lost is the third damage.

4. The method according to claim 1, wherein, the damage factor λ i is obtained by the following calculation model: where a, b represent water and underwater, respectively, i indicates the second damage level, ω ji represents the threshold value of the maximum deflection of the deformation in the j case of the i level of damage under the first damage level, l ji represents the threshold value of the maximum crack width in the j case of the i level of damage under the first damage level.

5. The method according to claim 4, wherein, The damage coefficient is obtained through the following calculation model:

6. The method according to claim 1, wherein, The second damage level is determined through the following model:

7. The method according to claim 1, wherein, The determination of the damage performance of the warship according to the second damage level and the first damage level comprises: taking the most serious damage level in the first damage level and the second damage level of the warship to be evaluated for damage performance as the evaluation damage level of the warship.

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