CN108595848B - Method and device for modeling bullet target action model in penetration process - Google Patents
Method and device for modeling bullet target action model in penetration process Download PDFInfo
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Abstract
The embodiment of the invention provides a method and a device for modeling a target shooting action model in a penetration process. The method comprises the following steps: acquiring parameters of a warhead; calculating to obtain a mass damping spring model of the warhead based on the axial vibration frequency, the warhead mass and each-order axial vibration damping; constructing a transfer function of the axial vibration of the warhead according to the mass damping spring model, and calculating according to the transfer function to obtain an elastic vibration model; and constructing a rigid motion model of the warhead, and combining the rigid motion model with the elastic vibration model to form a target action model. The device is used for executing the method, and the elastic vibration model is constructed, the elastic vibration model and the rigid motion model are combined to form the target action model, so that the influence of the elastic vibration of the warhead on the internal components of the warhead is more comprehensively analyzed, and the accuracy of the target action model for reflecting the stress condition of the internal components of the warhead is improved.
Description
Technical Field
The invention relates to the technical field of data modeling, in particular to a method and a device for modeling a target shooting action model in a penetration process.
Background
In modern war, the war warhead is increasingly dependent on ultra-high speed penetration to destroy high-strength hard targets such as defense works, surface ships, airport runways, ground buildings, aircraft shelter and the like. In the penetration process, the action mechanism of the warhead (bullet) between the warhead and the high-strength hard target (target) is very complex, and great difficulty is brought to the high-overload-resistant optimization design of internal components of the warhead, such as unclear mechanical input and unclear optimization direction.
At present, scholars at home and abroad disclose a target action mechanism between a warhead and a high-strength hard target by establishing a reasonable, effective and simplified target action model and guide the high-overload-resistant optimization design of internal components of the warhead, such as fuze and powder charge.
The existing bullet target action model modeling method only considers the rigid motion of the warhead, namely, the warhead does not deform in the penetration process. However, the warhead can be severely elastically deformed and even plastically deformed to a certain extent when penetrating a high-strength hard target, and the warhead cannot be directly assumed as a rigid body to comprehensively and reasonably describe the action process of the target. In addition, weapon electronics systems are more susceptible to damage under sinusoidal shock conditions, also suggesting that warhead elastic vibration is a critical factor affecting the survivability of internal components. Therefore, the missile action model considering the rigid body motion of the warhead cannot comprehensively and reasonably reflect the stress condition of the internal components of the warhead, and cannot really and effectively guide the high overload resistance optimization design of the internal components of the warhead.
Disclosure of Invention
In view of the above, an object of the embodiments of the present invention is to provide a method and an apparatus for modeling a missile target action model in a penetration process, so as to solve the above technical problems.
In a first aspect, an embodiment of the present invention provides a method for modeling a target shooting action model in a penetration process, including:
obtaining parameters of a warhead, the parameters including: the elastic modulus of the shell material, the density of the shell material, the length of the warhead, the mass of the warhead and each-step axial vibration damping;
calculating and obtaining the axial vibration frequency of each step of the warhead according to the elastic modulus of the shell material, the density of the shell material and the length of the warhead;
calculating and obtaining a mass damping spring model of the warhead based on the axial vibration frequency, the warhead mass and the various-order axial vibration damping;
constructing a transfer function of the axial vibration of the warhead according to the mass damping spring model, and calculating according to the transfer function to obtain an elastic vibration model;
and constructing a rigid motion model of the warhead, and combining the rigid motion model with the elastic vibration model to form a target action model.
Further, the calculating the axial vibration frequency of the warhead according to the shell material elastic modulus, the shell material density and the warhead length comprises:
according to the formula
Calculating and obtaining the axial vibration frequency of the warhead, wherein fBullet iThe axial vibration frequency of the ith order of the warhead, L the length of the warhead, E the elastic modulus of the shell material, and rho the density of the shell material.
Further, the parameters further include dimensionless damping ratios of the respective orders of axial vibration, and correspondingly, the calculating to obtain the mass damping spring model of the warhead based on the axial vibration frequency, the warhead mass and the respective orders of axial vibration damping includes:
calculating the natural angular frequency of each order of axial vibration according to the axial vibration frequency, calculating the rigidity of each order of axial vibration according to the mass of the warhead and the natural angular frequency, and calculating the damping of each order of axial vibration according to the rigidity of each order of axial vibration, the mass of the warhead and the dimensionless damping ratio;
and calculating to obtain a mass damping spring model of the warhead according to the mass of the warhead, the axial vibration damping of each step and the rigidity of the axial vibration of each step.
Further, the calculating the natural angular frequency of each order of axial vibration according to the axial vibration frequency includes:
according to omegaBullet i＝2πfBullet iCalculating the natural angular frequency of each order of axial vibration, wherein fBullet iThe axial vibration frequency of the ith order of the warhead;
the calculating the stiffness of each order of axial vibration according to the warhead mass and the natural angular frequency comprises:
according to
Calculating the stiffness of each order of axial vibration, wherein MBulletIs the warhead mass;
the calculating the each order axial vibration damping according to the each order axial vibration stiffness, the warhead mass and the dimensionless damping ratio comprises:
according to
Calculating the axial vibration damping of each order, wherein xiBullet iIs the dimensionless damping ratio.
Further, the transfer function is:
wherein Δ X(s) is the axial deformation, Fx(s) as a target force, GBullet i(s) is a transfer function of the elastic vibration of the ith order, and
MbulletFor the warhead mass, s is a complex field argument, CBullet iFor damping axial vibrations of the ith order, KBullet iIs the stiffness, ξ, of the ith order axial vibrationBullet iIs the i-th order dimensionless damping ratio.
Correspondingly, the obtaining of the elastic vibration model according to the transfer function calculation includes:
and performing partial differential calculation on the transfer function to obtain the elastic vibration model as follows:
further, the constructing the rigid body motion model of the warhead includes:
calculating the acting force of the target in the penetration process according to a cavity expansion theory and a differential surface element method;
and establishing the rigid motion model by utilizing Newton's second law based on the rigid kinematic theory.
Further, the obtaining of the target action model according to the rigid body motion model and the elastic vibration model includes:
and combining the rigid body motion model and the elastic vibration model to form the bullet target action model.
In a second aspect, an embodiment of the present invention provides a missile target action model modeling apparatus in a penetration process, including:
an obtaining module, configured to obtain parameters of a warhead, where the parameters include: the elastic modulus of the shell material, the density of the shell material, the length of the warhead, the mass of the warhead and each-step axial vibration damping;
the first calculation module is used for calculating and obtaining the axial vibration frequency of each step of the warhead according to the elastic modulus of the shell material, the density of the shell material and the length of the warhead;
the second calculation module is used for calculating and obtaining a mass damping spring model of the warhead based on the axial vibration frequency, the warhead mass and the axial vibration damping of each step;
the third calculation module is used for constructing a transfer function of the axial vibration of the warhead according to the mass damping spring model and calculating to obtain an elastic vibration model according to the transfer function;
and the construction module is used for constructing a rigid motion model of the warhead and combining the rigid motion model with the elastic vibration model to form a target action model.
Further, the first calculating module is specifically configured to:
according to the formula
Calculating and obtaining the axial vibration frequency of the warhead, wherein fBullet iThe axial vibration frequency of the ith order of the warhead, L the length of the warhead, E the elastic modulus of the shell material, and rho the density of the shell material.
Further, the parameter further includes a dimensionless damping ratio of each order of axial vibration, and correspondingly, the second calculation module is specifically configured to:
calculating the natural angular frequency of each order of axial vibration according to the axial vibration frequency, calculating the rigidity of each order of axial vibration according to the mass of the warhead and the natural angular frequency, and calculating the damping of each order of axial vibration according to the rigidity of each order of axial vibration, the mass of the warhead and the dimensionless damping ratio;
and calculating to obtain a mass damping spring model of the warhead according to the mass of the warhead, the axial vibration damping of each step and the rigidity of the axial vibration of each step.
According to the method and the device for modeling the missile target action model in the penetration process, the elastic vibration model is constructed, the elastic vibration model and the rigid motion model are combined to form the missile target action model, the influence of the elastic vibration of the warhead on internal components of the warhead is analyzed more comprehensively, and therefore the accuracy of the missile target action model for reflecting the stress condition of the internal components of the warhead is improved.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the embodiments of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
FIG. 1 is a schematic flow chart of a method for modeling a target shooting effect model in an implementation process according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a model of a mass damping spring according to an embodiment of the present invention;
FIG. 3 is a block diagram of the transfer function of the warhead vibration provided by an embodiment of the present invention;
FIG. 4 is a schematic structural diagram of a missile target action model modeling device in the penetration process according to an embodiment of the present invention;
fig. 5 is a block diagram of an electronic device according to an embodiment of the present disclosure.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present invention, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.
Fig. 1 is a schematic flow chart of a method for modeling a target play model in a penetration process according to an embodiment of the present invention, as shown in fig. 1, the method includes:
step 101: obtaining parameters of a warhead, the parameters including: the elastic modulus of the shell material, the density of the shell material, the length of the warhead, the mass of the warhead and each-step axial vibration damping;
in a specific implementation process, because the types of the warheads are different and the corresponding related parameters are different, before constructing a target action model of the warheads, the parameters of the warheads are acquired, wherein the parameters may include: the elastic modulus of the shell material, the density of the shell material, the length of the warhead, the mass of the warhead, and the axial vibration damping of each step, it should be noted that the parameters of the warhead may also include other parameters, which is not specifically limited in the embodiment of the present invention.
Step 102: calculating and obtaining the axial vibration frequency of each step of the warhead according to the elastic modulus of the shell material, the density of the shell material and the length of the warhead;
in a specific implementation process, when the shape of the warhead is an axisymmetric cylindrical rod, modal analysis is carried out according to the elastic modulus of the shell material, the density of the shell material and the length of the warhead, and the axial vibration frequency of each order of the warhead is obtained through calculation.
Step 103: calculating and obtaining a mass damping spring model of the warhead based on the axial vibration frequency, the warhead mass and the various-order axial vibration damping;
in a specific implementation process, after the axial vibration frequency of each order of the warhead is obtained through calculation, a mass damping spring model of the warhead can be established on the basis of the axial vibration frequency, the warhead mass and each order of axial vibration damping. It is understood that the warhead mass refers to the weight of the warhead itself.
Step 104: constructing a transfer function of the axial vibration of the warhead according to the mass damping spring model, and calculating according to the transfer function to obtain an elastic vibration model;
in a specific implementation process, after a mass damping spring model is obtained through calculation, a transfer function with the acting force of the warhead as input and the axial deformation as output axial vibration can be constructed by using the mass damping spring model, and then partial differential calculation is performed on the transfer function obtained through calculation to obtain a partial differential equation, wherein the partial differential equation is an elastic vibration model.
Step 105: and constructing a rigid motion model of the warhead, and combining the rigid motion model with the elastic vibration model to form a target action model.
In a specific implementation, the collision between the warhead and the high-strength hard target is equivalent to applying a target-shooting force with a fast loading rate to the warhead in the axial direction, and the assumption is that Fx. The acting force of the target can cause the deceleration movement of the warhead, namely the rigid body movement; on the other hand, multi-step axial vibration, namely elastic deformation of the warhead is excited and transmitted to internal components of the warhead, so that the survivability of the internal components is influenced. Therefore, in the process of the actual warhead to penetrate the high-strength hard target at high speed, the warhead moves in a rigid body mode, and the warhead vibrates elastically, so that the target action model can be divided into a rigid body motion model and an elastic vibration model. Therefore, a rigid motion model of the warhead needs to be constructed, and it should be noted that the construction of the rigid motion model is consistent with the construction method in the prior art, that is, a motion differential equation set in the penetration process is established through newton's second law, which is not described again in the embodiments of the present invention. And combining the constructed rigid body motion model and the constructed elastic vibration model to form a bullet target action model. It is understood that a rigid body motion model and an elastic vibration model can be combined to serve as a target action model.
According to the embodiment of the invention, the elastic vibration model is constructed, and the elastic vibration model and the rigid motion model are combined to form the target action model, so that the influence of the elastic vibration of the warhead on the internal components of the warhead is more comprehensively analyzed, and the accuracy of the target action model reflecting the stress condition of the internal components of the warhead is improved.
On the basis of the above embodiment, the obtaining of the axial vibration frequency of the warhead by calculating according to the elastic modulus of the shell material, the density of the shell material and the length of the warhead includes:
according to the formula
Calculating and obtaining the axial vibration frequency of the warhead, wherein fBullet iThe axial vibration frequency of the ith order of the warhead, L the length of the warhead, E the elastic modulus of the shell material, and rho the density of the shell material.
In a specific implementation process, the inherent characteristics of the axial vibration of the warhead can be obtained through modal analysis, that is, the axial vibration frequency of the warhead obtained by solving a one-dimensional wave equation according to the formula (1) can be obtained. Wherein, formula (1) is:
wherein f isBullet iIn the embodiment of the present invention, the axial vibration frequency of the ith order of the warhead is represented by i, where i is a positive integer, optionally, the maximum value of i may be 5, or may be other values.
According to the embodiment of the invention, the axial vibration frequency of each step of the warhead is obtained through formula calculation, and a data basis is provided for the construction of an elastic vibration model, so that the combination of the elastic vibration model and a rigid motion model as the high overload resistant optimization design of the internal components of the warhead provides more accurate mechanical design input and a more definite optimization design direction.
On the basis of the above embodiment, the parameters further include a dimensionless damping ratio of each order of axial vibration, and correspondingly, the calculating and obtaining a mass damping spring model of the warhead based on the axial vibration frequency, the warhead mass and each order of axial vibration damping includes:
calculating the natural angular frequency of each order of axial vibration according to the axial vibration frequency, calculating the rigidity of each order of axial vibration according to the mass of the warhead and the natural angular frequency, and calculating the damping of each order of axial vibration according to the rigidity of each order of axial vibration, the mass of the warhead and the dimensionless damping ratio;
and calculating to obtain a mass damping spring model of the warhead according to the mass of the warhead, the axial vibration damping of each step and the rigidity of the axial vibration of each step.
In a specific implementation process, the natural angular frequency of the axial vibration of each step of the warhead can be obtained through calculation according to the axial vibration frequency of each step of the warhead. And after the natural angular frequency is obtained through calculation, calculating and obtaining the rigidity of each step of axial vibration of the warhead according to the mass of the warhead and the calculated natural angular frequency. In addition, the parameters corresponding to the warhead also comprise the dimensionless damping ratio of each order of axial vibration, and the axial vibration damping of each order can be calculated according to the calculated rigidity of each order of axial vibration, the mass of the warhead and the dimensionless damping ratio.
FIG. 2 is a schematic diagram of a model of a mass damping spring according to an embodiment of the present invention, as shown in FIG. 2, according to a warhead mass MBulletAxial vibration damping C of each step corresponding to the warheadBullet iStiffness K of each order of axial vibrationBullet iAnd calculating the axial deformation delta X to obtain a mass damping spring model of the warhead, so as to form the mass damping spring model of the warhead. It will be understood that L is the length of the warhead, FxActing force of the warhead.
According to the embodiment of the invention, the mass damping spring model of the warhead is obtained through the mass of the warhead, the axial vibration damping of each step and the rigidity calculation of each step of axial vibration, so that the elastic vibration model corresponding to the warhead can be accurately obtained, and the accuracy of analyzing the stress condition of the internal components in the penetration process of the warhead is further improved.
On the basis of the above embodiment, the calculating the natural angular frequency of each order of axial vibration according to the axial vibration frequency includes:
according to omegaBullet i＝2πfBullet iCalculating the axial vibration of each stepAn angular frequency of which fBullet iThe axial vibration frequency of the ith order of the warhead.
In a specific implementation, the calculation of the natural angular frequency of each order of axial vibration of the bucket may be obtained according to equation (2), where equation (2) is as follows:
ωbullet i＝2πfBullet i (2)
Wherein, ω isBullet iNatural angular frequency, f, of each order of axial vibration of the warheadBullet iFor the ith axial vibration frequency of the warhead, it is understood that i is a positive integer, and the maximum value can be set according to actual conditions.
The calculating the stiffness of each order of axial vibration according to the warhead mass and the natural angular frequency comprises:
according to
Calculating the stiffness of each order of axial vibration, wherein MBulletIs the warhead mass.
In a specific implementation process, after the natural angular frequency of each order of axial vibration is obtained through calculation, the natural angular frequency is substituted into a formula (3), so that the stiffness of each order of axial vibration of the warhead can be obtained through calculation, wherein the formula (3) is as follows:
thus, according to the warhead mass MBulletAnd the natural angular frequency omega of each step of axial vibration of the warhead obtained by calculationBullet iThe stiffness of each order of axial vibration can be calculated.
The calculating the each order axial vibration damping according to the each order axial vibration stiffness, the warhead mass and the dimensionless damping ratio comprises:
according to
Calculating the axial vibration damping of each step, wherein，ξBullet iIs the dimensionless damping ratio.
In a specific implementation process, after the stiffness of each order of axial vibration of the warhead is obtained through calculation, the stiffness is substituted into a formula (4), so that each order of axial vibration damping corresponding to the warhead can be obtained through calculation, wherein the formula (4) is as follows:
wherein ξBullet iDimensionless damping ratio, M, for the warheadBulletFor battle sector quality, KBullet iThe rigidity of each stage of axial vibration of the warhead.
According to the embodiment of the invention, the mass damping spring model of the warhead is obtained through calculating the mass of the warhead, the axial vibration damping of each step, the rigidity of each step of axial vibration and the axial deformation, the elastic vibration model corresponding to the warhead can be accurately obtained, and the accuracy of analyzing the stress condition of the internal components of the warhead in the penetration process is further improved.
On the basis of the above embodiment, the transfer function is:
wherein Δ X(s) is the axial deformation, Fx(s) as a target force, GBullet i(s) is a transfer function of the elastic vibration of the ith order, and
MbulletFor the warhead mass, s is a complex field argument, CBullet iFor damping axial vibrations of the ith order, KBullet iIs the stiffness, ξ, of the ith order axial vibrationBullet iIs the i-th order dimensionless damping ratio.
In a specific implementation, fig. 3 is a block diagram of a transfer function of the warhead vibration provided by an embodiment of the invention, as shown in fig. 3, from input FxThe transfer function from(s) to output Δ x(s) is shown in equation (5):
wherein Δ X(s) is the axial deformation of the warhead, Fx(s) impact between the warhead and the hard object of high strength during penetration, target force applied to the warhead, GBullet i(s) is a transfer function of the elastic vibration of the ith order, and
optionally, a value of n may be 5, 6, or 7, or may be other values, which may be set according to an actual situation, which is not specifically limited in this embodiment of the present invention, and M isBulletFor battle mass, s is an independent variable of the complex field, CBullet iDamping of the ith order axial vibration, which can be calculated according to equation (4), KBullet iIs the stiffness of the ith order axial vibration and can be obtained by calculation according to the formula (3), ξBullet iIs the i-th order dimensionless damping ratio.
Correspondingly, the obtaining of the elastic vibration model according to the transfer function calculation includes:
and performing partial differential calculation on the transfer function to obtain the elastic vibration model as follows:
in a specific implementation process, the partial differential calculation is performed on the formula (5), and the calculation result is shown as the formula (6):
the formula (6) is a partial differential equation of the axial vibration of the warhead, and the partial differential equation is an elastic vibration model. It is understood that the meaning of each parameter in the formula (6) is the same as that in the above embodiment, and is not described herein again.
According to the embodiment of the invention, from the perspective of multi-disciplinary fusion of solid mechanics, automatic control, mechanical vibration and the like, the elastic vibration model is established, and the elastic vibration model and the rigid motion model are combined to obtain the target action model, so that more accurate mechanical design input and more definite optimization design direction can be provided for the high overload resistance optimization design of the internal components of the warhead.
On the basis of the above embodiment, the constructing the rigid body motion model of the warhead includes:
calculating the acting force of the target in the penetration process according to a cavity expansion theory and a differential surface element method;
and establishing the rigid motion model by utilizing Newton's second law based on the rigid kinematic theory.
In the specific implementation process, as for the construction of a rigid body motion model of a warhead, firstly, a stress analysis model of a warhead penetration process is established, and a cavity expansion theory and a differential surface element method are adopted to solve the bullet target acting force in the penetration process; and then, based on a rigid body kinematics theory, establishing an end point ballistic model, namely a motion differential equation set in the penetration process, by adopting a Newton's second law, and finally, solving the end point ballistic model by adopting a numerical integration method by taking the acting force of the bullet target as input to obtain the change rule of displacement, speed and overload along with time, and guiding the high overload resistance optimization design of the internal components of the warhead.
According to the embodiment of the invention, a rigid motion model is established by utilizing Newton's second law, and then the constructed elastic vibration model is combined to form a target action model of the warhead, so that the stress analysis of the interior of the warhead in the penetration process can be reasonably carried out through the target action model.
On the basis of the above embodiments, the obtaining a target action model according to the rigid body motion model and the elastic vibration model includes:
and combining the rigid body motion model and the elastic vibration model to form the bullet target action model.
Specifically, after the rigid motion model and the elastic vibration model are constructed respectively, an equation formed by simultaneously establishing equations corresponding to the rigid motion model and the elastic vibration model is the target-impacting model.
According to the embodiment of the invention, the elastic vibration model is constructed, and the elastic vibration model and the rigid motion model are combined to form the target action model, so that the influence of the elastic vibration of the warhead on the internal components of the warhead is more comprehensively analyzed, and the accuracy of the target action model reflecting the stress condition of the internal components of the warhead is improved.
Fig. 4 is a schematic structural diagram of a missile target action model modeling device in the penetration process according to an embodiment of the present invention, and as shown in fig. 4, the device includes: an acquisition module 401, a first calculation module 402, a second calculation module 403, a third calculation module 404 and a construction module 405, wherein,
the obtaining module 401 is configured to obtain parameters of a battle portion, where the parameters include: the elastic modulus of the shell material, the density of the shell material, the length of the warhead, the mass of the warhead and each-step axial vibration damping; the first calculation module 402 is used for calculating and obtaining the axial vibration frequency of each step of the warhead according to the elastic modulus of the shell material, the density of the shell material and the length of the warhead; the second calculation module 403 is configured to calculate and obtain a mass damping spring model of the warhead based on the axial vibration frequency, the warhead mass, and the respective orders of axial vibration damping; the third calculation module 404 is configured to construct a transfer function of the axial vibration of the warhead according to the mass damping spring model, and calculate an elastic vibration model according to the transfer function; the construction module 405 is configured to construct a rigid motion model of the warhead, and combine the rigid motion model with the elastic vibration model to form a target action model.
In a specific implementation, before constructing the target-impacting model of the warhead, the obtaining module 401 obtains parameters of the warhead, where the parameters may include: the elastic modulus of the shell material, the density of the shell material, the length of the warhead, the mass of the warhead, and the axial vibration damping of each step, it should be noted that the parameters of the warhead may also include other parameters, which is not specifically limited in the embodiment of the present invention. When the shape of the warhead is an axisymmetric cylindrical rod, the first calculation module 402 performs modal analysis according to the elastic modulus of the shell material, the density of the shell material and the length of the warhead, and calculates and obtains the axial vibration frequency of each order of the warhead. After calculating the axial vibration frequencies of the various orders of the warhead, the second calculation module 403 can establish a mass damping spring model of the warhead based on the axial vibration frequencies, the warhead mass, and the various orders of axial vibration damping. It is understood that the warhead mass refers to the weight of the warhead itself. After obtaining the mass damping spring model through calculation, the third calculation module 404 may use the mass damping spring model to construct a transfer function of the axial vibration with the acting force of the warhead as input and the axial deformation as output, and then perform partial differential calculation on the transfer function obtained through calculation to obtain a partial differential equation, where the partial differential equation is an elastic vibration model. The construction module 405 constructs a rigid motion model and combines the constructed rigid motion model with the constructed elastic vibration model to form a target action model. It is understood that a rigid body motion model and an elastic vibration model can be combined to serve as a target action model.
According to the embodiment of the invention, the elastic vibration model is constructed, and the elastic vibration model and the rigid motion model are combined to form the target action model, so that the influence of the elastic vibration of the warhead on the internal components of the warhead is more comprehensively analyzed, and the accuracy of the target action model reflecting the stress condition of the internal components of the warhead is improved.
On the basis of the foregoing embodiment, the first calculation module is specifically configured to:
according to the formula
Calculating and obtaining the axial vibration frequency of the warhead, wherein fBullet iThe axial vibration frequency of the ith order of the warhead, L the length of the warhead, E the elastic modulus of the shell material, and rho the density of the shell material.
On the basis of the foregoing embodiment, the parameter further includes a dimensionless damping ratio of each order of axial vibration, and correspondingly, the second calculation module is specifically configured to:
calculating the natural angular frequency of each order of axial vibration according to the axial vibration frequency, calculating the rigidity of each order of axial vibration according to the mass of the warhead and the natural angular frequency, and calculating the damping of each order of axial vibration according to the rigidity of each order of axial vibration, the mass of the warhead and the dimensionless damping ratio;
and calculating to obtain a mass damping spring model of the warhead according to the mass of the warhead, the axial vibration damping of each step, the rigidity of the axial vibration of each step and the axial deformation.
On the basis of the above embodiment, the calculating the natural angular frequency of each order of axial vibration according to the axial vibration frequency includes:
according to omegaBullet i＝2πfBullet iCalculating the natural angular frequency of each order of axial vibration, wherein fBullet iThe axial vibration frequency of the ith order of the warhead;
the calculating the stiffness of each order of axial vibration according to the warhead mass and the natural angular frequency comprises:
according to
Calculating the stiffness of each order of axial vibration, wherein MBulletIs the warhead mass;
the calculating the each order axial vibration damping according to the each order axial vibration stiffness, the warhead mass and the dimensionless damping ratio comprises:
according to
Calculating the axial vibration damping of each order, wherein xiBullet iIs the dimensionless damping ratio.
On the basis of the above embodiment, the transfer function is:
wherein Δ X(s) is the axial deformation, Fx(s) as a target force, GBullet i(s) is a transfer function of the elastic vibration of the ith order, and
MbulletFor the warhead mass, s is a complex field argument, CBullet iFor damping axial vibrations of the ith order, KBullet iIs the stiffness, ξ, of the ith order axial vibrationBullet iIs the i-th order dimensionless damping ratio.
Correspondingly, the third computing module is specifically configured to:
and performing partial differential calculation on the transfer function to obtain the elastic vibration model as follows:
on the basis of the above embodiment, the building module is specifically configured to:
calculating the acting force of the target in the penetration process according to a cavity expansion theory and a differential surface element method;
and establishing the rigid motion model by utilizing Newton's second law based on the rigid kinematic theory.
On the basis of the foregoing embodiments, the building module is specifically configured to:
and combining the rigid body motion model and the elastic vibration model to form the bullet target action model.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working process of the apparatus described above may refer to the corresponding process in the foregoing method, and will not be described in too much detail herein.
In summary, the elastic vibration model is constructed, the elastic vibration model and the rigid motion model are combined to form the target action model, and the influence of the elastic vibration of the warhead on the internal components of the warhead is analyzed more comprehensively, so that the accuracy of the target action model for reflecting the stress condition of the internal components of the warhead is improved.
Referring to fig. 5, fig. 5 is a block diagram of an electronic device according to an embodiment of the present disclosure. The electronic device may include a modeling apparatus 501, a memory 502, a storage controller 503, a processor 504, a peripheral interface 505, an input output unit 506, an audio unit 507, and a display unit 508.
The memory 502, the memory controller 503, the processor 504, the peripheral interface 505, the input/output unit 506, the audio unit 507, and the display unit 508 are electrically connected to each other directly or indirectly, so as to realize data transmission or interaction. For example, the components may be electrically connected to each other via one or more communication buses or signal lines. The modeling apparatus 501 includes at least one software function module that can be stored in the memory 502 in the form of software or firmware (firmware) or solidified in an Operating System (OS) of the modeling apparatus 501. The processor 504 is adapted to execute executable modules stored in the memory 502, such as software functional modules or computer programs comprised by the modeling apparatus 501.
The Memory 502 may be, but is not limited to, a Random Access Memory (RAM), a Read Only Memory (ROM), a Programmable Read-Only Memory (PROM), an Erasable Read-Only Memory (EPROM), an electrically Erasable Read-Only Memory (EEPROM), and the like. The memory 502 is used for storing a program, and the processor 504 executes the program after receiving an execution instruction, and the method executed by the server defined by the flow process disclosed in any of the foregoing embodiments of the present invention may be applied to the processor 504, or implemented by the processor 504.
The processor 504 may be an integrated circuit chip having signal processing capabilities. The Processor 504 may be a general-purpose Processor, and includes a Central Processing Unit (CPU), a Network Processor (NP), and the like; but may also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components. The various methods, steps and logic blocks disclosed in the embodiments of the present invention may be implemented or performed. A general purpose processor may be a microprocessor or the processor 504 may be any conventional processor or the like.
The peripheral interface 505 couples various input/output devices to the processor 504 and to the memory 502. In some embodiments, the peripheral interface 505, the processor 504, and the memory controller 503 may be implemented in a single chip. In other examples, they may be implemented separately from the individual chips.
The input and output unit 506 is used for providing input data for a user to realize the interaction of the user with the server (or the local terminal). The input/output unit 506 may be, but is not limited to, a mouse, a keyboard, and the like.
The display unit 508 provides an interactive interface (e.g., a user interface) between the electronic device and a user or for displaying image data to a user reference. In this embodiment, the display unit 508 may be a liquid crystal display or a touch display. In the case of a touch display, the display can be a capacitive touch screen or a resistive touch screen, which supports single-point and multi-point touch operations. Supporting single-point and multi-point touch operations means that the touch display can sense touch operations from one or more locations on the touch display at the same time, and the sensed touch operations are sent to the processor 504 for calculation and processing.
The peripheral interface 505 couples various input/output devices to the processor 504 and to the memory 502. In some embodiments, the peripheral interface 505, the processor 504, and the memory controller 503 may be implemented in a single chip. In other examples, they may be implemented separately from the individual chips.
The input/output unit 506 is used for providing input data for a user to realize the interaction of the user and the processing terminal. The input/output unit 506 may be, but is not limited to, a mouse, a keyboard, and the like.
It will be appreciated that the configuration shown in fig. 5 is merely illustrative and that the electronic device may include more or fewer components than shown in fig. 5 or may have a different configuration than shown in fig. 5. The components shown in fig. 5 may be implemented in hardware, software, or a combination thereof.
In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented in other ways. The apparatus embodiments described above are merely illustrative, and for example, the flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
In addition, the functional modules in the embodiments of the present invention may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.
The functions, if implemented in the form of software functional modules and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
Claims (10)
1. A method for modeling a target shooting action model in a penetration process is characterized by comprising the following steps:
obtaining parameters of a warhead, the parameters including: the elastic modulus of the shell material, the density of the shell material, the length of the warhead, the mass of the warhead and each-step axial vibration damping;
calculating and obtaining the axial vibration frequency of each step of the warhead according to the elastic modulus of the shell material, the density of the shell material and the length of the warhead;
calculating and obtaining a mass damping spring model of the warhead based on the axial vibration frequency, the warhead mass and the various-order axial vibration damping;
constructing a transfer function of the axial vibration of the warhead according to the mass damping spring model, and calculating according to the transfer function to obtain an elastic vibration model;
and constructing a rigid motion model of the warhead, and combining the rigid motion model with the elastic vibration model to form a target action model.
2. The method of claim 1, wherein said calculating an axial vibration frequency of the warhead from the shell material modulus of elasticity, the shell material density, and the warhead length comprises:
according to the formula
Calculating and obtaining the axial vibration frequency of the warhead, wherein fBullet iIs the axial vibration frequency of the ith order of the warhead, and L is the length of the warheadAnd E is the elastic modulus of the shell material, and rho is the density of the shell material.
3. The method of claim 1, wherein the parameters further include a dimensionless damping ratio for each order of axial vibration, and wherein the calculating a mass damping spring model for the warhead based on the axial vibration frequency, the warhead mass, and the each order of axial vibration damping comprises:
calculating the natural angular frequency of each order of axial vibration according to the axial vibration frequency, calculating the rigidity of each order of axial vibration according to the mass of the warhead and the natural angular frequency, and calculating the damping of each order of axial vibration according to the rigidity of each order of axial vibration, the mass of the warhead and the dimensionless damping ratio;
and calculating to obtain a mass damping spring model of the warhead according to the mass of the warhead, the axial vibration damping of each step and the rigidity of the axial vibration of each step.
4. The method of claim 3, wherein said calculating the natural angular frequency of each order of axial vibration from said axial vibration frequency comprises:
according to omegaBullet i＝2πfBullet iCalculating the natural angular frequency of each order of axial vibration, wherein fBullet iThe axial vibration frequency of the ith order of the warhead;
the calculating the stiffness of each order of axial vibration according to the warhead mass and the natural angular frequency comprises:
according to
Calculating the stiffness of each order of axial vibration, wherein MBulletIs the warhead mass;
the calculating the each-order axial vibration damping according to the stiffness of each-order axial vibration, the mass of the warhead and the dimensionless damping ratio comprises:
according to
Calculating the axial vibration damping of each order, wherein xiBullet iIs the dimensionless damping ratio.
5. The method of claim 1, wherein the transfer function is:
wherein Δ X(s) is the axial deformation, Fx(s) as a target force, GBullet i(s) is a transfer function of the elastic vibration of the ith order, and
MbulletFor the warhead mass, s is a complex field argument, CBullet iFor damping axial vibrations of the ith order, KBullet iIs the stiffness, ξ, of the ith order axial vibrationBullet iIs the dimensionless damping ratio of the ith order; omegaBullet iIs the natural angular frequency of the ith order axial vibration;
correspondingly, the obtaining of the elastic vibration model according to the transfer function calculation includes:
and performing partial differential calculation on the transfer function to obtain the elastic vibration model as follows:
6. the method of claim 1, wherein the constructing the rigid body motion model of the warhead comprises:
calculating the acting force of the target in the penetration process according to a cavity expansion theory and a differential surface element method;
and establishing the rigid motion model by utilizing Newton's second law based on the rigid kinematic theory.
7. The method according to any one of claims 1-6, wherein the obtaining a target play model from the rigid body motion model and the elastic vibration model comprises:
and combining the rigid body motion model and the elastic vibration model to form the bullet target action model.
8. A bullet target effect model modeling device in the penetration process is characterized by comprising:
an obtaining module, configured to obtain parameters of a warhead, where the parameters include: the elastic modulus of the shell material, the density of the shell material, the length of the warhead, the mass of the warhead and each-step axial vibration damping;
the first calculation module is used for calculating and obtaining the axial vibration frequency of each step of the warhead according to the elastic modulus of the shell material, the density of the shell material and the length of the warhead;
the second calculation module is used for calculating and obtaining a mass damping spring model of the warhead based on the axial vibration frequency, the warhead mass and the axial vibration damping of each step;
the third calculation module is used for constructing a transfer function of the axial vibration of the warhead according to the mass damping spring model and calculating to obtain an elastic vibration model according to the transfer function;
and the construction module is used for constructing a rigid motion model of the warhead and combining the rigid motion model with the elastic vibration model to form a target action model.
9. The apparatus of claim 8, wherein the first computing module is specifically configured to:
according to the formula
Calculating and obtaining the axial vibration frequency of the warhead, wherein fBullet iIs the i-th order axial vibration frequency of the warhead, L is the length of the warhead, E is the elastic modulus of the shell material, and rho isThe shell material density.
10. The apparatus according to claim 8, wherein the parameters further include a dimensionless damping ratio of each order of axial vibration, and correspondingly, the second calculating means is specifically configured to:
calculating the natural angular frequency of each order of axial vibration according to the axial vibration frequency, calculating the rigidity of each order of axial vibration according to the mass of the warhead and the natural angular frequency, and calculating the damping of each order of axial vibration according to the rigidity of each order of axial vibration, the mass of the warhead and the dimensionless damping ratio;
and calculating to obtain a mass damping spring model of the warhead according to the mass of the warhead, the axial vibration damping of each step and the rigidity of the axial vibration of each step.
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| CN106214182A (en) * | 2016-07-06 | 2016-12-14 | 西安交通大学 | HIFU damaging shear ripple elastic characteristic method of estimation based on LK optical flow method |
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