CN217157290U

CN217157290U - Multi-scale hierarchical triangular anti-impact structure

Info

Publication number: CN217157290U
Application number: CN202220547736.0U
Authority: CN
Inventors: 尹剑飞; 程乾; 温激鸿; 郁殿龙
Original assignee: National University of Defense Technology
Current assignee: National University of Defense Technology
Priority date: 2022-03-14
Filing date: 2022-03-14
Publication date: 2022-08-09
Anticipated expiration: 2032-03-14

Abstract

The utility model belongs to the technical field of triangle-shaped shocks resistance, a multiscale hierarchy triangle structure of shocking resistance is disclosed, the inside triangle-shaped that inlays and have different geometry of triangle hierarchy structure, the triangle level is equipped with macroscale triangle-shaped, and macroscale triangle-shaped is inside to be inlayed and to have mesoscale triangle-shaped, and it has microscale triangle-shaped to inlay in the mesoscale triangle-shaped. The mesoscale triangle divides the macroscale triangle into four regions, the uppermost end of the four regions is a first region, the middle of the four regions is a second region, the left lower end of the four regions is a third region, and the right lower end of the four regions is a fourth region. Micro-scale triangles are embedded in the first area, the third area and the fourth area. Has higher compression resistance and energy absorption. Under static compression, the energy absorption characteristic of the multi-scale level triangle is increased by about two times compared with that of a single-scale triangle grid structure, the energy absorption characteristic is partially improved under dynamic impact, and the multi-scale level triangle can be used for structural design of compression-resistant and impact-resistant sandwich plates and has good engineering application value.

Description

Multi-scale hierarchical triangular anti-impact structure

Technical Field

The utility model belongs to the technical field of triangle-shaped shocks resistance, especially, relate to a multi-scale level triangle-shaped structure of shocking resistance.

Background

At present, the impact resistance is a key technical index of equipment such as large armored vehicles, ships, aircraft carriers and the like, and the battlefield viability is concerned. It is a common technical means at present to absorb the blast impact energy by laying a sacrificial layer on the outside of the equipment in the area susceptible to the blast, and by plastic deformation and destruction of the sacrificial layer. In consideration of the overall performance and actual working conditions of large equipment, the design of the light-weight high-strength impact-resistant energy-absorbing structure has important significance for improving the armor protection capability and ensuring the armor safety.

The honeycomb material has the characteristics of good mechanical property and light weight, and is widely used in the related engineering field at present. For a honeycomb structure, the topological form of the minimum periodic unit has a great influence on the mechanical properties of a macroscopic structure, such as the mechanical properties of triangular, quadrilateral and kagome honeycombs are quite different. The purpose of improving the performance of the honeycomb structure is achieved by designing the topological structure of a single cell, and the method is a key focus field of researchers. With the high requirements on quality, strength, rigidity and the like in modern equipment, the common honeycomb structure is difficult to meet the engineering application requirements, and a hierarchical structure design thought with macro-micro multi-scale provides a technical approach for improving the static and dynamic mechanical properties of the honeycomb structure.

A hierarchical structure is a structure having macro-micro multi-scale features where the micro-structures have macrostructurally similar topological features that are assembled into a new structure in addition to or in place of a side or corner of the macro-structure. The introduction of the microstructure can obviously enhance the mechanical property of the structure on the premise of keeping the structure quality and the volume meeting the application requirements, and is applied to the fields of aerospace, engineering construction and the like at present.

The utility model discloses based on multiscale hierarchy structural design, designed an anti-impact explosion-proof structure of triangle level, compare with traditional triangle grid structure, can be under the unchangeable circumstances of holding quality, show the compressive property and the shock resistance characteristic that promote the structure, have good engineering application prospect.

Through the above analysis, the problems and defects of the prior art are as follows: the common honeycomb structure is difficult to meet the engineering application requirements, and a hierarchical structure design idea with macro-micro multi-scale provides a technical approach for improving the static and dynamic mechanical properties of the honeycomb structure.

SUMMERY OF THE UTILITY MODEL

In order to solve the problems existing in the prior art, the utility model provides a multi-scale level triangle-shaped structure of shocking resistance.

The utility model discloses a realize like this, a multi-scale level triangle-shaped structure of shocking resistance is provided with:

a triangular hierarchy; the triangular structure is characterized in that triangular shapes with different geometries are embedded in the triangular hierarchical structure, a macro-scale triangle is arranged on the triangular hierarchy, an mesoscale triangle is embedded in the macro-scale triangle, and a micro-scale triangle is embedded in the mesoscale triangle.

Furthermore, the mesoscale triangle divides the macroscale triangle into four regions, the uppermost end of the four regions is a first region, the middle of the four regions is a second region, the left lower end of the four regions is a third region, and the right lower end of the four regions is a fourth region.

Furthermore, micro-scale triangles are embedded in the first area, the third area and the fourth area.

Furthermore, the size proportion of the macroscale triangle, the mesoscale triangle and the microscale triangle is 0.5, namely the side length of the mesoscale triangle is half of the macroscale, the size of the microscale triangle is half of the mesoscale triangle, the three triangles are contacted without a gap, and the stress wave can be continuously transmitted in the structure.

Further, in the multi-scale hierarchical triangular structure, macro-scale triangles are periodically arranged, and a single periodic unit of the macro-scale triangles can be obtained through translation and rotation of the hierarchical triangles.

Combine foretell all technical scheme, the utility model discloses the advantage that possesses and positive effect are:

novel triangle hierarchical structure compares in triangle grid structure, has higher compression resistance characteristic and energy-absorbing characteristic. Under static compression, the energy absorption characteristic of the multi-scale level triangle is increased by nearly two times compared with that of a single-scale triangular grid structure, the energy absorption characteristic is partially improved under dynamic impact, and the multi-scale level triangle can be used for structural design of compression-resistant and impact-resistant sandwich plates and has good engineering application value.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained from the drawings without creative efforts.

Fig. 1 is a schematic view of a multi-scale hierarchical triangle shock-resistant structure provided by an embodiment of the present invention.

Fig. 2 is a schematic view of a single-scale triangular grid structure and a multi-scale triangular-level impact-resistant structure provided by the embodiment of the present invention.

Fig. 3 is a stress-strain curve of three structures under quasi-static compression and different impact velocities according to an embodiment of the present invention.

FIG. 4 is a stress-strain curve diagram of a multi-scale triangular hierarchical structure and a single-scale triangular grid structure at low speed (5m/s) and high speed (100m/s)

In the figure: 1. a macro scale triangle; 2. a mesoscale triangle; 3. a microscale triangle; 4. a first region; 5. a second region; 6. a third region; 7. and a fourth region.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

To the problem that prior art exists, the utility model provides a structure is strikeed to level triangle-shaped of multiscale, it is right below combining the figure the utility model discloses do detailed description.

The utility model aims at overcoming the not enough scheduling problem of triangle grid structure compressive property, energy-absorbing characteristic under certain mass constraint and volume constraint that exist in the above-mentioned background, and designed a novel anti-impact blast resistant structure of triangle level. This novel triangle hierarchical structure compares in triangle grid structure, has higher resistance to compression characteristic and energy-absorbing characteristic. Under static compression, the energy absorption characteristic of the multi-scale level triangle is increased by nearly two times compared with that of a single-scale triangular grid structure, the energy absorption characteristic is partially improved under dynamic impact, and the multi-scale level triangle can be used for structural design of compression-resistant and impact-resistant sandwich plates and has good engineering application value.

The purpose of the utility model can be realized through the following technical scheme:

the utility model provides a multiscale triangle level shock-resistant structure comprises a plurality of level cycle units of mxn, and wherein m is horizontal cell number, and n is the vertical number of piles, and m more than or equal to 1, n more than or equal to 1. In a single hierarchical periodic unit, four multi-scale hierarchical triangles are symmetrically arranged; the single-level triangle can be obtained by filling a meso-scale triangle and three micro-scale triangles in a macro-scale triangle. The multi-scale triangular-level impact-resistant structure can be applied to the design of sandwich beams and sandwich boards, has good compression-resistant, impact-resistant and energy-absorbing characteristics, and practically and effectively reduces the damage degree of the protected structure.

The multi-scale triangular hierarchical structure, the composition materials and the geometric dimension can be adjusted according to specific engineering application conditions.

Establishing a simulation model in LS-DYNA finite element software according to the designed triangular hierarchical structure, wherein the formed material is TPU, and the material parameters are as follows: the density of 1168kg/cm3, Poisson's ratio of 0.48, elastic modulus of 72.25MPa, tangent modulus of 10.74MPa, yield modulus of 2.747MPa, and stress limit of 25.5417 MPa. The side length of the macroscale triangle is 2cm, and the side lengths of the mesoscopic triangle and the microscale triangle are 1cm and 0.5cm respectively. For proving the utility model provides a multiscale triangle-shaped hierarchical structure's excellent performance establishes single yardstick triangle-shaped and multiscale triangle-shaped as the contrast, for guaranteeing that three kinds of structures have the same equivalent density, macroscopical, mesoscopic and multiscale triangle-shaped structure wall thickness is 0.3cm, 0.15cm and 0.088cm respectively.

The stress-strain curves of the three structures under quasi-static compression and at different impact velocities were extracted, as shown in fig. 3.

To evaluate the energy absorption characteristics of the structure, the energy absorption characteristics of the structure were calculated from the stress-strain curves of the structure under compression and impact:

in the formula, delta _D For the densification stroke of the structure under the compression condition, f (x) is the compression force.

And extracting the densification strain, initial peak stress, energy absorption characteristic and platform area average stress of the structure according to the simulated stress-strain curve for evaluating the structure performance. The densification strain is the stroke required by the structure in the stage of compressing to be incompressible, the initial peak stress is the compressive force required by the structure in the stage of yielding, the plateau area average stress is the average stress after the structure enters the stage of yielding until densification, and the energy absorption characteristic is the energy required by the structure in the stage of compressing from the initial state to densification.

Graph 1 gives the data relating to the three structures under quasi-static compression and graph 2 gives the data relating to the structures at different impact velocities. It can be seen that under quasi-static compression, the multi-scale triangular hierarchical structure has better compression resistance and energy absorption characteristics. Under the condition of the same mass and volume, the compression resistance characteristic of the multi-scale triangular hierarchical structure is improved by 34.2% compared with that of a single-scale triangular grid structure, and the energy absorption characteristic is improved by about twice.

Chart 1

Chart 2

Fig. 4 shows the stress-strain curves of the multi-scale triangular hierarchical structure and the single-scale triangular grating structure at low speed (5m/s) and high speed (100 m/s). It can be seen from the figure that under low-speed and high-speed impact, the multi-scale triangular hierarchical structure has better energy absorption characteristic, and in the impact process, the stress value fluctuation is smoother, so that the protection of a protected structure is more facilitated.

To sum up, the utility model discloses the technological effect who has does:

1. has good compression resistance and energy absorption. Compared with the traditional single-scale triangular grid structure, the multi-scale triangular hierarchical structure can obviously improve the energy absorption characteristic under the premise of the same quality, the energy absorption characteristic of the structure is improved by nearly three times in quasi-static compression, and the energy absorption characteristic of the multi-scale triangular hierarchical structure is slightly higher than that of the single-scale triangular grid structure in dynamic impact.

2. Under dynamic impact working conditions, stress-strain curves of the multi-scale triangular hierarchical structure are more gentle, fluctuation is smaller, and the multi-scale triangular hierarchical structure is more uniform in deformation under the impact working conditions, so that transient impact of the protective structure on the protected structure is reduced, and the protective structure can be more effective.

3. The multi-scale triangular hierarchical structure provided by the invention has the characteristics of highly adjustable and controllable materials and geometric dimensions, can be adjusted according to actual application working conditions, and has good engineering application value.

As shown in fig. 1 and 2, the embodiment of the utility model provides a multiscale hierarchy triangle shock-resistant structure triangle hierarchical structure is inside to be inlayed and to have the triangle of different geometry, and the triangle level is equipped with macroscale triangle 1, and macroscale triangle 1 is inside to be inlayed and to have mesoscale triangle 2, and it has microscale triangle 3 to inlay in mesoscale triangle 2.

The mesoscale triangle 2 divides the macroscale triangle 1 into four regions, the uppermost end of the four regions is a first region 4, the middle of the four regions is a second region 5, the left lower end of the four regions is a third region 6, and the right lower end of the four regions is a fourth region 7.

Micro-scale triangles 3 are embedded in the first region 4, the third region 6 and the fourth region 7.

The structural size proportion of the macroscale triangle 1, the mesoscale triangle 2 and the microscale triangle 3 is 0.5, namely the side length of the mesoscale triangle 2 is half of the size of the macroscale triangle 1, the size of the microscale triangle 3 is half of the size of the mesoscale triangle 2, no gap is contacted between the three triangles, and the stress wave can be continuously transmitted in the structure.

In the multi-scale hierarchical triangular structure, macroscale triangles are periodically arranged, and a single periodic unit of the macroscale triangles can be obtained through translation and rotation of the hierarchical triangles.

The utility model discloses the theory of operation of structure is shocked resistance to level triangle-shaped of many yards: a mesoscale triangle 2 is embedded in the macroscale triangle 1, and a microscale triangle 3 is embedded in the mesoscale triangle 2. Novel triangle hierarchical structure compares in triangle grid structure, has higher compression resistance characteristic and energy-absorbing characteristic. Under static compression, the energy absorption characteristic of the multi-scale level triangle is increased by about two times compared with that of a single-scale triangle grid structure, the energy absorption characteristic is partially improved under dynamic impact, and the multi-scale level triangle can be used for structural design of compression-resistant and impact-resistant sandwich plates and has good engineering application value.

In the description of the present invention, "a plurality" means two or more unless otherwise specified; the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "head", "tail", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are merely for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be covered within the protection scope of the present invention by those skilled in the art within the technical scope of the present invention.

Claims

1. A multi-scale hierarchical triangular impact-resistant structure, characterized in that it is provided with:

a triangular hierarchy;

the triangular structure is characterized in that triangular shapes with different geometries are embedded in the triangular hierarchical structure, a macro-scale triangle is arranged on the triangular hierarchy, an mesoscale triangle is embedded in the macro-scale triangle, and a micro-scale triangle is embedded in the mesoscale triangle.

2. The multi-scale, hierarchical, triangular impact-resistant structure according to claim 1, wherein the mesoscale triangles divide the macroscale triangle into four regions, the four regions being a first region at the top, a second region in the middle, a third region at the bottom left, and a fourth region at the bottom right.

3. The multi-scale, hierarchical triangular impact-resistant structure of claim 2, wherein micro-scale triangles are embedded within the first, third, and fourth regions.

4. The multi-scale hierarchical triangular impact-resistant structure according to claim 1, wherein the dimensional proportions of the macro-scale triangle, the meso-scale triangle and the micro-scale triangle are all 0.5, that is, the side length of the meso-scale triangle is half of the macro size, the size of the micro-scale triangle is half of the meso-scale triangle, the three triangles are contacted without a gap, and the stress wave can be continuously propagated in the structure.

5. The multi-scale, hierarchical, triangular impact-resistant structure according to claim 1, wherein the macro-scale triangles of the multi-scale, hierarchical, triangular structure are periodically arranged, and the single periodic unit of the macro-scale triangles of the multi-scale, hierarchical, triangular structure can be obtained by translation and rotation of the hierarchical triangles.