Negative Poisson's ratio star-shaped grating sandwich plate combined with acoustic black hole effect
By combining the design with the acoustic black hole effect, the negative Poisson's ratio star-shaped grid sandwich panel has achieved significant improvements in low-frequency vibration suppression and acoustic performance, realizing more efficient vibration and noise control, widening the bandgap frequency range, and improving vibration transmission loss in the 10Hz-10000Hz frequency band.
Patent Information
- Application Number
- CN202510940733.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-09
- Publication Date
- 2025-10-17
AI Technical Summary
Existing negative Poisson's ratio grid sandwich panels have limitations in low-frequency vibration suppression and acoustic performance, especially in certain special occasions with higher acoustic requirements, and the vibration and noise reduction effects need to be further improved.
A negative Poisson's ratio star-shaped grid sandwich panel combined with the acoustic black hole effect is designed. By sandwiching a one-dimensional acoustic black hole connecting beam between the negative Poisson's ratio star-shaped grid unit and the two-dimensional acoustic black hole panel unit, the wave concentration and dissipation effect of the acoustic black hole effect is utilized to construct a centrally symmetrical four-pointed star-shaped frame structure to achieve efficient vibration and noise control.
The vibration bandgap frequency is shifted to low frequency, the bandgap frequency range is widened, the vibration transmission loss in the 10Hz-10000Hz frequency band is improved, and a more efficient vibration reduction and noise reduction effect is achieved, especially noise control in the grille bandgap frequency band.
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Figure CN120808737A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of vibration and noise reduction, and more particularly to a negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect. BACKGROUND
[0002] In the field of modern structural engineering and acoustics, lightweight, high-strength and high-performance structural design has always been the focus of research. Sandwich panels, as a typical composite material structure, are widely used in aerospace, automobile manufacturing and construction due to their excellent stiffness, strength and vibration isolation performance. In the sandwich panel, the negative Poisson's ratio grid is used as the core layer, which has a unique mechanical property of increasing in lateral size under tension and decreasing in lateral size under compression, giving the structure significant advantages in energy absorption, impact protection, vibration reduction and sound insulation. With the continuous optimization of negative Poisson's ratio grid, the sandwich panel structure has good vibration and noise reduction performance, but in some special occasions with higher acoustic requirements, the negative Poisson's ratio grid sandwich panel still has certain limitations in controlling vibration and acoustic performance, especially in low-frequency vibration suppression, which still needs to be further improved. SUMMARY
[0003] The technical problem to be solved by the present application is to provide a negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect, which can improve the vibration and noise reduction effect of the negative Poisson's ratio star-shaped grid sandwich panel.
[0004] The technical scheme adopted by the present application to solve the technical problem is: a negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect is constructed, which includes an array of negative Poisson's ratio star-shaped grid units and two-dimensional acoustic black hole panel units. The negative Poisson's ratio star-shaped grid unit is sandwiched between two two-dimensional acoustic black hole panel units. The cross section of the negative Poisson's ratio star-shaped grid unit is a central symmetric four-star frame structure, and a one-dimensional acoustic black hole connecting beam is extended at the four outer corners of the four-star frame structure.
[0005] In the above scheme, adjacent negative Poisson's ratio star-shaped grid units are connected by one-dimensional acoustic black hole connecting beams.
[0006] In the above scheme, the one-dimensional acoustic black hole connecting beam is wedge-shaped, and the cross-sectional thickness of the one-dimensional acoustic black hole connecting beam changes according to the power function required to achieve the acoustic black hole effect.
[0007] In the above scheme, the two-dimensional acoustic black hole panel unit is a square thin plate, and the center of the four-star frame structure is at the corresponding place of the square thin plate as the center of the acoustic black hole area. A two-dimensional acoustic black hole structure is constructed, and the cross-sectional thickness of the two-dimensional acoustic black hole structure changes according to the power function.
[0008] In the scheme, the negative Poisson's ratio star-shaped grid unit is made of metal material.
[0009] In the scheme, the acoustic black hole panel unit is made of metal material.
[0010] In the scheme, the negative Poisson's ratio star-shaped grid unit is integrally casted.
[0011] In the scheme, the negative Poisson's ratio star-shaped grid unit and the two-dimensional acoustic black hole panel unit are joined by welding.
[0012] The negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect has the following beneficial effects: 1. Based on the acoustic black hole effect, the negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect is designed to achieve more efficient vibration and noise control, and realize the comprehensive performance of lightweight, high strength and high efficiency.
[0013] 2. Compared with the traditional grid, the vibration band gap frequency of the new grid moves to low frequency, the band gap frequency range is widened, and the vibration and noise reduction effect of the structure can be effectively improved.
[0014] 3. Compared with the traditional prototype sandwich panel, the overall vibration transmission loss of the new sandwich panel involved in the application is improved in the frequency range of 10Hz-10000Hz, and the transmission loss is higher than that of the traditional prototype sandwich panel in the band gap frequency range of the grid, realizing more efficient vibration and noise control. BRIEF DESCRIPTION OF DRAWINGS
[0015] The application will be further described below with reference to the drawings and examples, wherein: Figure 1a is a structural schematic diagram of the negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect of the application; Figure 1b is a structural schematic diagram of figure 1 without the upper panel; Figure 2a is a structural schematic diagram of the negative Poisson's ratio star-shaped grid unit; Figure 2b is a top view of the negative Poisson's ratio star-shaped grid unit; Figure 3a is a structural schematic diagram of the one-dimensional acoustic black hole grid connecting beam; Figure 3b is a sectional view of the one-dimensional acoustic black hole grid connecting beam; Figure 4a is a structural schematic diagram of the two-dimensional acoustic black hole panel unit; Figure 4b is a sectional view of the two-dimensional acoustic black hole panel unit; Figure 5a is a traditional star-shaped lattice vibration band gap diagram; Figure 5b is a lattice vibration band gap diagram of the sandwich panel of the present application; Figure 6 is a vibration transmission loss comparison diagram of the traditional prototype and the sandwich panel of the present application. DETAILED DESCRIPTION
[0016] In order to have a clearer understanding of the technical features, objectives and effects of the present application, the specific embodiments of the present application will be described in detail with reference to the accompanying drawings.
[0017] The present application provides a negative Poisson's ratio star-shaped lattice sandwich panel combined with acoustic black hole effect. The specific embodiments are described in detail as follows: Figure 1a The present application provides a negative Poisson's ratio star-shaped lattice sandwich panel combined with acoustic black hole effect. The specific embodiments are described in detail as follows: Figure 1b The present application provides a negative Poisson's ratio star-shaped lattice sandwich panel combined with acoustic black hole effect. The specific embodiments are described in detail as follows: The negative Poisson's ratio star-shaped lattice sandwich panel combined with acoustic black hole effect of the present application comprises arrayed negative Poisson's ratio star-shaped lattice units 2 and two-dimensional acoustic black hole panel units 1, and the negative Poisson's ratio star-shaped lattice units 2 are clamped between the two two-dimensional acoustic black hole panel units 1. The cross section of the negative Poisson's ratio star-shaped lattice unit 2 is a central-symmetrical four-corner star-shaped frame structure 201, and a one-dimensional acoustic black hole connecting beam 202 extends at the four outer corners of the four-corner star-shaped frame structure 201.
[0018] Figure 2a The present application provides a negative Poisson's ratio star-shaped lattice unit 2, which is composed of a central-symmetrical four-corner star-shaped frame structure 201 and a one-dimensional acoustic black hole lattice connecting beam 202 extending at the four outer corners of the four-corner star-shaped frame structure 201, Figure 2b The present application provides a top view of the negative Poisson's ratio star-shaped lattice unit 2. The inner corner of the four-corner star-shaped frame structure 201 is 30°, the outer corner is 120°, the inner side length of the four-corner star-shaped frame is 24 mm, the outer side length is 30 mm (excluding the overlapping part of the outer side of the star-shaped frame and the connecting beam, which is originally 33.2 mm), the frame width is 3 mm, and the thickness is 10 mm (i.e. the core layer thickness of the sandwich panel).
[0019] Figure 3a The present application provides a one-dimensional acoustic black hole lattice connecting beam 202 structure diagram, Figure 3b The present application provides a one-dimensional acoustic black hole lattice connecting beam 202 structure diagram, The one-dimensional acoustic black hole lattice connecting beam 202 is a symmetrical structure from top to bottom, with a length of 36 mm, a width of 5.6 mm, a right end thickness of 10 mm, and a left end thickness of 0.39 mm. From the left end, the one-dimensional acoustic black hole region is 31 mm long, and the cross-sectional thickness change follows a power function with the left end midpoint as the coordinate origin:
[0020] wherein the range interval of x is [0, 31] with unit of mm, i.e. the power-law form geometric shape thickness is 5mm, the maximum length is 31mm, and the initial position offset is 0.195mm.
[0021] Figure 4a A structural schematic diagram of a two-dimensional acoustic black hole panel unit 1 (the diagram is a lower panel unit, and the upper and lower panel structures are the same) provided by the application, Figure 4b A structural section schematic diagram, the square panel unit side length is 100mm, the thickness is 2mm, the panel center is taken as an acoustic black hole area dot, the two-dimensional acoustic black hole area 101 radius is 20mm, the truncation thickness is 0.5mm, and the panel lower surface center is taken as a coordinate origin, and the section thickness change follows a power function:
[0022] wherein the range interval of x is [-20, 20] with unit of mm, i.e. the power-law form geometric shape thickness is 2mm, the maximum radius is 20mm, and the initial position offset is 0.5mm.
[0023] The negative Poisson's ratio star-shaped grid unit shown in Figure 2a 、 Figure 2b and the two-dimensional acoustic black hole panel unit shown in Figure 4a 、 Figure 4b are joined to form a negative Poisson's ratio star-shaped grid sandwich panel unit combining the acoustic black hole effect proposed by the application, and the unit is arranged through an array to constitute a grid sandwich panel structure for realizing vibration and noise reduction, as shown in Figure 1a 、 Figure 1b .
[0024] Preferably, the negative Poisson's ratio star-shaped grid unit is made of a metal material.
[0025] Preferably, the acoustic black hole panel unit is made of a metal material.
[0026] Preferably, the negative Poisson's ratio star-shaped grid unit is integrally cast into shape.
[0027] Preferably, the negative Poisson's ratio star-shaped grid unit and the two-dimensional acoustic black hole panel unit are joined through welding.
[0028] Figure 5a A vibration band gap diagram of a traditional star-shaped grid, Figure 5bFor the vibration band gap chart (band gap refers to the frequency range in which sound waves or elastic waves cannot propagate in the structure, which is caused by the strong scattering effect of the periodic structure of the material on the wave) of the new lattice involved in the present application, the traditional star lattice and the lattice of the present application have comparable sizes, and the difference between the two is whether the acoustic black hole effect is combined into the lattice structure, that is, whether a one-dimensional acoustic black hole connecting beam is used. It can be found that compared with the traditional lattice, the vibration band gap frequency of the new lattice moves to low frequency, the band gap frequency range is widened, and the vibration and noise reduction effect of the structure can be effectively improved.
[0029] Figure 6 For the vibration transmission loss curve comparison chart of the new sandwich panel involved in the present application and the traditional prototype sandwich panel, both have comparable sizes, and the difference between the two is whether the acoustic black hole effect is combined into the sandwich panel structure, that is, whether a one-dimensional acoustic black hole connecting beam and a two-dimensional acoustic black hole panel are used. The ideal acoustic black hole structure can guide and absorb sound waves or elastic waves, so that the energy is gradually concentrated to achieve the effect of almost no reflection absorption. It can be found that compared with the traditional prototype sandwich panel, the overall vibration transmission loss of the new sandwich panel involved in the present application in the frequency range of 10Hz-10000Hz is improved, and in the band gap frequency range of the lattice, the transmission loss is higher than that of the traditional prototype sandwich panel, realizing more efficient vibration and noise control.
[0030] The embodiments of the present application are described above in combination with the drawings, but the present application is not limited to the above specific embodiments, and the above specific embodiments are only illustrative and not restrictive. Those skilled in the art can make many forms under the inspiration of the present application without departing from the purpose of the present application and the scope protected by the claims, and these all belong to the protection of the present application.
Claims
1. A negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect, characterized in that: It includes an array-arranged negative Poisson's ratio star-shaped grating unit and a two-dimensional acoustic black hole panel unit. The negative Poisson's ratio star-shaped grating unit is sandwiched between two two-dimensional acoustic black hole panel units. The cross-section of the negative Poisson's ratio star-shaped grating unit is a centrally symmetrical four-pointed star frame structure, and one-dimensional acoustic black hole connecting beams extend from the four outer corners of the four-pointed star frame structure.
2. The negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect according to claim 1, characterized in that: Adjacent negative Poisson's ratio star-shaped grid units are connected by one-dimensional acoustic black hole connecting beams.
3. The negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect according to claim 1, characterized in that: The one-dimensional acoustic black hole connecting beam is wedge-shaped, and the cross-sectional thickness of the one-dimensional acoustic black hole connecting beam changes according to the power function required to achieve the acoustic black hole effect.
4. The negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect according to claim 1, characterized in that: The two-dimensional acoustic black hole panel unit is a square thin plate. The center of the four-pointed star frame structure is corresponding to the square thin plate as the center of the acoustic black hole area to construct a two-dimensional acoustic black hole structure. The cross-sectional thickness of the two-dimensional acoustic black hole structure changes according to a power function.
5. The negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect according to claim 1, characterized in that: The negative Poisson's ratio star-shaped grid unit is made of metal material.
6. The negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect according to claim 1, characterized in that: The acoustic black hole panel unit is made of metal material.
7. The negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect according to claim 1, characterized in that: The negative Poisson's ratio star-shaped grid unit is integrally cast.
8. The negative Poisson's ratio star-shaped grid sandwich panel combined with acoustic black hole effect according to claim 1, characterized in that: The negative Poisson's ratio star-shaped grid unit is joined to the two-dimensional acoustic black hole panel unit by welding.