阅读说明：本技术 一种复杂多模耦合声学超材料板 (Complex multimode coupling acoustic metamaterial plate ) 是由 吴昱东 任霞光 丁渭平 杨明亮 邓世奇 于 2021-10-20 设计创作，主要内容包括：本发明公开了一种复杂多模耦合声学超材料板,包括六边形单元,六边形单元包括六个三角形单元,三角形单元包括阻尼层、基体层和局域共振单元,基体层位于阻尼层上,局域共振单元固定于基体层上。局域共振单元包括悬臂梁模块和质量块模块,悬臂梁模块包括第一悬臂梁、第二悬臂梁、第三悬臂梁、第四悬臂梁和第五悬臂梁,质量块模块包括第一层质量块、第二层质量块、第三层质量块、第四层质量块和第五层质量块。本发明所提供的一种复杂多模耦合声学超材料板,具有很强的低频隔振能力,每个三角形单元内若干不同质量块以串并联方式连接,形成较宽禁带。同时多个三角形单元可设计出不同的禁带,组合形成更宽禁带,进一步提高抑振效果。(The invention discloses a complex multimode coupling acoustic metamaterial plate which comprises hexagonal units, wherein each hexagonal unit comprises six triangular units, each triangular unit comprises a damping layer, a base layer and a local resonance unit, the base layer is positioned on the damping layer, and the local resonance unit is fixed on the base layer. The local resonance unit comprises a cantilever beam module and a mass block module, wherein the cantilever beam module comprises a first cantilever beam, a second cantilever beam, a third cantilever beam, a fourth cantilever beam and a fifth cantilever beam, and the mass block module comprises a first layer of mass block, a second layer of mass block, a third layer of mass block, a fourth layer of mass block and a fifth layer of mass block. The complex multimode coupling acoustic metamaterial plate provided by the invention has strong low-frequency vibration isolation capability, and a plurality of different mass blocks in each triangular unit are connected in series and parallel to form a wider forbidden band. Meanwhile, different forbidden bands can be designed for the triangular units, and the triangular units are combined to form a wider forbidden band, so that the vibration suppression effect is further improved.)

1. A complex multimode-coupled acoustic metamaterial plate, comprising: the novel hexagonal base plate comprises hexagonal units, wherein the hexagonal units comprise six triangular units, each triangular unit comprises a damping layer (1), a base layer (2) and a local resonance unit, the base layer (2) is located on the damping layer (1), and the local resonance unit is fixed on the base layer (2).

2. The complex multimode-coupled acoustic metamaterial plate of claim 1, wherein: the local resonance unit comprises a cantilever beam module and a mass block module, the cantilever beam module comprises a first cantilever beam (3), a second cantilever beam (4), a third cantilever beam (5), a fourth cantilever beam (6) and a fifth cantilever beam (7), the mass block module comprises a first layer of mass block (8), the mass block comprises a second layer of mass block (9), a third layer of mass block (10), a fourth layer of mass block (11) and a fifth layer of mass block (12), wherein the first layer of mass block (8) is connected with a base layer (2) through a first cantilever beam (3), the second layer of mass block (9) is connected with the first layer of mass block (8) through a second cantilever beam (4), the third layer of mass block (10) is connected with the second layer of mass block (9) through a third cantilever beam (5), the fourth layer of mass block (11) is connected with the second layer of mass block (10) through a fourth cantilever beam (6), and the fifth layer of mass block (12) is connected with the second layer of mass block (11) through a fifth cantilever beam (7).

3. The complex multimode-coupled acoustic metamaterial plate of claim 1, wherein: the number of second layer quality piece (9) is two and parallelly connected, the number of third layer quality piece (10) is four, and parallelly connected between four third layer quality pieces (10), the number of fourth layer quality piece (11) is four, and parallelly connected between four fourth layer quality pieces (11), the number of fifth layer quality piece (12) is two and parallelly connected, and the number of second cantilever beam (4) is the same with the number of second layer quality piece (9), and the number of third cantilever beam (5) is the same with the number of third layer quality piece (10), and the number of fourth cantilever beam (6) is the same with the number of fourth layer quality piece (11), and the number of fifth cantilever beam (7) is the same with the number of fifth layer quality piece (12).

4. The complex multimode-coupled acoustic metamaterial plate of claim 1, wherein: the size and the thickness of the first layer of mass block (8), the second layer of mass block (9), the third layer of mass block (10), the fourth layer of mass block (11) and the fifth layer of mass block (12) are reduced in sequence.

5. The complex multimode-coupled acoustic metamaterial plate of claim 1, wherein: the length of the first cantilever beam (3), the second cantilever beam (4), the third cantilever beam (5), the fourth cantilever beam (6) and the fifth cantilever beam (7) is increased in sequence, and the width is decreased in sequence.

6. The complex multimode-coupled acoustic metamaterial plate of claim 1, wherein: the base layer (2), the cantilever beam module and the mass block module are made of steel.

7. The complex multimode-coupled acoustic metamaterial plate of claim 1, wherein: damping layer (1) is magnetism hot melt damping layer, and base member layer (2) and damping layer (1) are directly hot-melt through the mode of toasting and are integrative, and magnetism hot melt damping layer has magnetism, can directly adsorb on the metal wallboard.

8. The complex multimode-coupled acoustic metamaterial plate of claim 1, wherein: the triangular units are in an equilateral triangle structure.

Technical Field

The invention belongs to the technical field of vibration noise control and functional composite material crossing, and particularly relates to a complex multi-mode coupling acoustic metamaterial plate.

Background

Comfort has even become the first element of customer demand today. Therefore, automotive NVH performance, which is directly related to comfort, has been of high interest to a wide range of users. In addition, the NVH performance of the automobile also has a close influence on the safety and physical and psychological health of the driver. When a vehicle with poor NVH performance is driven for a long time, the attention of a driver is easily dispersed, the incidence rate of traffic safety accidents is increased, and the diseases such as insomnia, dreaminess, memory deterioration and the like are easily caused to the driver and passengers.

The characteristics of strong penetrating power and difficult attenuation of the medium-low frequency vibration wave are always hot spots and difficult problems in automobile vibration noise control. In engineering applications, there are mainly 3 ways for conventional damping of low frequency vibrations of body panel parts:

first, using conventional damping vibration damping materials or rubber vibration damping materials, the vibration energy of the attenuating structure is dissipated and its radiated noise is reduced by the damping material being adhered to the structural member. Both theory and experimental research show that the mode has obvious attenuation on high-frequency vibration, but has poor effect in a low-frequency band.

Secondly, the floor plates or the reinforcing ribs are added on the vehicle body wall plates which have larger contribution to the noise in the vehicle, and the natural frequency of the floor plates in the low frequency band is improved by increasing the local rigidity. However, in practical operation, the frequency increase range is limited, and the structure of the wall plate is greatly changed, so that the production cost is increased sharply, and the economic benefit of enterprises is seriously affected.

Thirdly, a dynamic vibration absorber is mounted on the wall structure. However, the operating band is narrow, and there are many restrictions in terms of installation space, weight reduction, durability, cost control, and the like.

The appearance of the acoustic metamaterial brings new ideas and methods for controlling the low-and-medium-frequency vibration noise. The band gap characteristics of the peculiar vibration absorption and isolation metamaterial are formed by changing the 'artificial cells' in the material.

A unit cell unit in the existing vehicle acoustic metamaterial low-frequency sound insulation vibration attenuation structure only has one design frequency, if the absorption of vibration of a plurality of frequencies is to be realized, the forbidden band can be widened only in a unit parallel connection or structure array mode, but the mode can increase the occupied space of the metamaterial structure on one hand and limit the application range of the metamaterial structure, and on the other hand, the widened frequency band is still narrow, the mode is not rich enough, and the vibration suppression effect is general.

Therefore, an acoustic metamaterial structure which can be used in a narrow space and has a wider acoustic forbidden band is needed, and the acoustic metamaterial has a wider application range and a better vibration suppression effect.

Disclosure of Invention

The invention aims to solve the problems and provide a complex multimode coupling acoustic metamaterial with wide application range and good vibration suppression effect.

In order to solve the technical problems, the technical scheme of the invention is as follows: the utility model provides a complicated multimode coupling acoustics metamaterial plate, includes the hexagon unit, and the hexagon unit includes six triangle-shaped units, and the triangle-shaped unit includes damping layer, base member layer and local resonance unit, and the base member layer is located the damping layer, and local resonance unit is fixed in on the base member layer.

Preferably, the local resonance unit comprises a cantilever beam module and a mass block module, the cantilever beam module comprises a first cantilever beam, a second cantilever beam, a third cantilever beam, a fourth cantilever beam and a fifth cantilever beam, the mass block module comprises a first layer mass block, a second layer mass block, a third layer mass block, a fourth layer mass block and a fifth layer mass block, the first layer mass block is connected with the base layer through the first cantilever beam, the second layer mass block is connected with the first layer mass block through the second cantilever beam, the third layer mass block is connected with the second layer mass block through the third cantilever beam, the fourth layer mass block is connected with the second layer mass block through the fourth cantilever beam, and the fifth layer mass block is connected with the second layer mass block through the fifth cantilever beam.

Preferably, the quantity of second layer quality piece is two and parallelly connected, the quantity of third layer quality piece is four, and parallelly connected between the four third layer quality pieces, the quantity of fourth layer quality piece is four, and parallelly connected between the four fourth layer quality pieces, the quantity of fifth layer quality piece is two and parallelly connected, and the quantity of second cantilever beam is the same with the quantity of second layer quality piece, and the quantity of third cantilever beam is the same with the quantity of third layer quality piece, and the quantity of fourth cantilever beam is the same with the quantity of fourth layer quality piece, and the quantity of fifth cantilever beam is the same with the quantity of fifth layer quality piece.

Preferably, the sizes and the thicknesses of the first layer mass block, the second layer mass block, the third layer mass block, the fourth layer mass block and the fifth layer mass block are reduced in sequence.

Preferably, the lengths of the first cantilever beam, the second cantilever beam, the third cantilever beam, the fourth cantilever beam and the fifth cantilever beam are sequentially increased, and the widths are sequentially decreased.

Preferably, the base layer, the cantilever beam modules and the mass modules are made of steel.

Preferably, the damping layer is a magnetic hot-melt damping layer, the base layer and the damping layer are directly hot-melted into a whole in a baking mode, and the magnetic hot-melt damping layer has magnetism and can be directly adsorbed on the metal wall plate.

Preferably, the triangular units are in an equilateral triangle structure.

The invention has the beneficial effects that:

1. the complex multimode coupling acoustic metamaterial plate provided by the invention has strong low-frequency vibration isolation capability, and a plurality of different mass blocks in each triangular unit are connected in series-parallel connection to generate rich modes and form a wider forbidden band. Meanwhile, different forbidden bands can be designed for the triangular units, and the triangular units are combined to form a wider forbidden band, so that the vibration suppression effect is further improved.

2. The complex multimode coupling acoustic metamaterial plate provided by the invention is small in overall thickness, small in occupied space and wide in application range. In a particular engineering application, one or more hexagonal cells are used when the installation space is relatively large. When the space is small, one or more triangle elements are used.

3. The back of the complex multimode coupling acoustic metamaterial plate provided by the invention is made of a magnetic damping material, has magnetism, can be directly adsorbed on a metal wallboard, and is convenient to mount. And the damping can absorb a part of high-frequency vibration energy and can ensure the up-and-down vibration space of the local resonance unit.

4. The complex multimode coupling acoustic metamaterial plate provided by the invention is made of common materials, is convenient to process and is low in cost.

Drawings

FIG. 1 is a schematic diagram of the overall structure of a complex multimode-coupled acoustic metamaterial plate according to the present invention;

fig. 2 is a schematic view of the overall structure of the hexagonal cell of the present invention.

Fig. 3 is a front view of a hexagonal cell of the present invention.

Fig. 4 is a schematic diagram of the overall structure of the inventive triangular unit.

Fig. 5 is a front view of an inventive triangular unit.

Figure 6 is a side view of an inventive triangular unit.

FIG. 7 is a schematic structural diagram of a rectangular metamaterial plate composed of hexagonal cells according to the invention.

FIG. 8 is a graph comparing frequency response functions of the complex multimode coupling acoustic metamaterial plate, a single-oscillator acoustic metamaterial plate with the same size and a common plate.

Description of reference numerals: 1. a damping layer; 2. a substrate layer; 3. a first cantilever beam; 4. a second cantilever beam; 5. a third cantilever beam; 6. a fourth cantilever beam; 7. a fifth cantilever beam; 8. a first layer of proof masses; 9. a second layer of proof mass; 10. a third layer of mass blocks; 11. a fourth layer of mass blocks; 12. and a fifth layer mass block.

Detailed Description

The invention is further described with reference to the following figures and specific embodiments:

as shown in fig. 1 to 8, the complex multimode-coupled acoustic metamaterial plate provided by the invention comprises hexagonal units, each hexagonal unit comprises six triangular units, each triangular unit comprises a damping layer 1, a base layer 2 and a local resonance unit, the base layer 2 is positioned on the damping layer 1, and the local resonance unit is fixed on the base layer 2.

In the present embodiment, the triangle unit is an equilateral triangle structure, and the side length is 200 mm. The thickness of base member layer 2 is 1mm, and damping layer 1 is only attached in base member layer 2's periphery, and local resonance unit below does not have damping layer 1, and damping layer 1's thickness is 2 mm.

The local area resonance unit comprises a cantilever beam module and a mass block module, the cantilever beam module comprises a first cantilever beam 3, a second cantilever beam 4, a third cantilever beam 5, a fourth cantilever beam 6 and a fifth cantilever beam 7, the mass block module comprises a first layer mass block 8, a second layer mass block 9, a third layer mass block 10, a fourth layer mass block 11 and a fifth layer mass block 12, the first layer mass block 8 is connected with the base layer 2 through the first cantilever beam 3, the second layer mass block 9 is connected with the first layer mass block 8 through the second cantilever beam 4, the third layer mass block 10 is connected with the second layer mass block 9 through the third cantilever beam 5, the fourth layer mass block 11 is connected with the second layer mass block 10 through the fourth cantilever beam 6, and the fifth layer mass block 12 is connected with the second layer mass block 11 through the fifth cantilever beam 7.

The quantity of second layer quality piece 9 is two and parallelly connected, the quantity of third layer quality piece 10 is four, and parallelly connected between four third layer quality pieces 10, the quantity of fourth layer quality piece 11 is four, and parallelly connected between four fourth layer quality pieces 11, the quantity of fifth layer quality piece 12 is two and parallelly connected, and the quantity of second cantilever beam 4 is the same with the quantity of second layer quality piece 9, and the quantity of third cantilever beam 5 is the same with third layer quality piece 10, and the quantity of fourth cantilever beam 6 is the same with fourth layer quality piece 11, and the quantity of fifth cantilever beam 7 is the same with fifth layer quality piece 12.

The sizes and the thicknesses of the first layer mass block 8, the second layer mass block 9, the third layer mass block 10, the fourth layer mass block 11 and the fifth layer mass block 12 are reduced in sequence.

In the present embodiment, the length, width, and height dimensions of the first layer mass block 8 are 145mm × 15mm × 3mm, the length, width, and height dimensions of the second layer mass block 9 are 46mm × 14mm × 2mm, the length, width, and height dimensions of the third layer mass block 10 are 12mm × 11mm × 1.5mm, the length, width, and height dimensions of the fourth layer mass block 11 are 7mm × 8mm × 1mm, and the length, width, and height dimensions of the fifth layer mass block 12 are 5mm × 6mm × 0.5mm, respectively.

The lengths of the first cantilever beam 3, the second cantilever beam 4, the third cantilever beam 5, the fourth cantilever beam 6 and the fifth cantilever beam 7 are increased in sequence, and the widths are decreased in sequence.

In the present embodiment, the first cantilever beam 3 has a size of 30mm × 10mm, the second cantilever beam 4 has a size of 20mm × 15mm, the third cantilever beam 5 has a size of 8mm × 20mm, the fourth cantilever beam 6 has a size of 3mm × 16mm, and the fifth cantilever beam 7 has a size of 2mm × 16 mm.

The base layer 2, the cantilever beam modules and the mass block modules are made of steel.

Damping layer 1 is magnetic hot melt damping layer, and base member layer 2 and damping layer 1 are directly hot-melt through the mode of toasting and are integrative, and magnetic hot melt damping layer has magnetism, can directly adsorb on the metal wallboard.

In practical engineering application, the number and arrangement of the triangular units or the hexagonal units can be selected according to design requirements to adapt to installation positions, and the thickness of the base layer 2, the number of layers of the mass block and the sizes of the mass block and the cantilever beam of each triangular unit can be modified to match a target forbidden band.

As shown in fig. 8, the complex multi-mode coupled acoustic metamaterial plate obtained according to the actual test data has a better vibration suppression effect compared with the frequency response function between the single-vibrator acoustic metamaterial plate and the common flat plate with the same size.

It will be appreciated by those of ordinary skill in the art that the embodiments described herein are intended to assist the reader in understanding the principles of the invention and are to be construed as being without limitation to such specifically recited embodiments and examples. Those skilled in the art can make various other specific changes and combinations based on the teachings of the present invention without departing from the spirit of the invention, and these changes and combinations are within the scope of the invention.