CN112652287B - Acoustic black hole sandwich panel vibration reduction structure - Google Patents
Acoustic black hole sandwich panel vibration reduction structure Download PDFInfo
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- CN112652287B CN112652287B CN202011477967.0A CN202011477967A CN112652287B CN 112652287 B CN112652287 B CN 112652287B CN 202011477967 A CN202011477967 A CN 202011477967A CN 112652287 B CN112652287 B CN 112652287B
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
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Abstract
An acoustic black hole sandwich panel vibration reduction structure relates to a sandwich panel. The invention solves the problems of complex structure and high price when the vibration reduction and noise reduction of the aircraft structure are realized by adopting an active control mode. The panel (1) and the backboard (3) are respectively provided with an orthogonal reinforcing plate (4) on one side plane, a plurality of cavities (7) are arranged in the orthogonal reinforcing plate (4), a plurality of acoustic black holes (5) are embedded in the upper side surface and the lower side surface of the double-side acoustic black hole embedded plate (2), a cut-off hole (6) is formed in the thinnest position of the acoustic black hole (5), the panel (1), the double-side acoustic black hole embedded plate (2) and the backboard (3) are fixedly connected in sequence from top to bottom, each acoustic black hole (5) in the double-side acoustic black hole embedded plate (2) is embedded into one cavity (7), and the acoustic black hole (5) embedded into the cavity (7) is of a single cell structure. The vibration reduction and noise reduction device is used for vibration reduction and noise reduction of an aircraft.
Description
Technical Field
The invention relates to a sandwich panel, in particular to an acoustic black hole sandwich panel vibration damping structure, which is a multilayer composite sound insulation vibration damping structure and belongs to the field of vibration and noise reduction of aerospace and ship structures.
Background
In the field of power machinery such as aerospace and ships, vibration and noise problems are common, and due to the existence of vibration and noise, normal operation of various devices of an aircraft is influenced, and living environments of workers are also greatly influenced, so that the vibration and noise problems in engineering in the field of aircraft are always emphasized by people. For the vibration damping and noise reduction problem of the aircraft structure, an active control method and a passive control method can be generally adopted to realize the vibration damping and noise reduction problem. The active control method can achieve vibration suppression performance of different frequency bands, but the active control method needs external energy input, and often needs to design a more complex control system, which is more complex and expensive in cost and design. The passive vibration reduction and noise reduction method is simple to implement, and the vibration reduction and vibration isolation system is applied to the vibration source and the propagation path thereof, so that the aim of suppressing the vibration of the structure can be fulfilled.
In summary, the existing active control method for solving the problem of vibration and noise reduction of the aircraft structure has the problems of complex structure and high price.
Disclosure of Invention
The invention aims to solve the problems of complex structure and high price when the vibration reduction and noise reduction of the aircraft structure are solved by adopting an active control mode. The performance of vibration reduction and noise reduction of the acoustic black hole structure and the vibration band gap adjusting capacity of the phonon crystal structure are combined, so that more reliable vibration suppression is realized, and the acoustic black hole sandwich panel vibration reduction structure is further provided.
The technical scheme includes that the acoustic black hole sandwich panel vibration damping structure comprises a panel, a bilateral acoustic black hole embedded plate and a back plate, wherein the panel and the back plate are square plates, orthogonal reinforcing plates are arranged on one side planes of the panel and the back plate, a plurality of cavities are formed in the orthogonal reinforcing plates, a plurality of acoustic black holes are embedded in the upper side face and the lower side face of the bilateral acoustic black hole embedded plate, a cut-off hole is formed in the thinnest position of the acoustic black hole in thickness, the panel, the bilateral acoustic black hole embedded plate and the back plate are fixedly connected in sequence from top to bottom, each acoustic black hole in the bilateral acoustic black hole embedded plate is embedded into one cavity, and the acoustic black holes embedded into the cavities are of a unit cell structure.
Furthermore, the panel and the back plate are both square flat plates, and the cavity is a square cavity.
Further, the panel, the bilateral acoustic black hole embedded plate and the back plate are fixedly connected in an adhesive or welding mode from top to bottom; or the panel, the bilateral acoustic black hole embedded plate and the back plate are integrally formed through 3D printing in the sequence from top to bottom.
Furthermore, the thickness of the panel and the back plate is 1mm-5mm, the height of the rib beam of the orthogonal stiffened plate is 5mm-30mm, and the thickness of the rib beam is 1mm-5 mm.
Furthermore, the material of the face plate and the back plate is polyvinyl chloride, polypropylene, polycarbonate, polyethylene, polymethyl methacrylate, glass fiber reinforced plastic or steel.
Further, the thickness of the double-side acoustic black hole embedded plate is 5mm-20 mm.
Further, the thickness of the cutting hole is 0.5mm-2 mm.
Furthermore, the material of the double-side acoustic black hole embedded plate is polyvinyl chloride, polypropylene, polycarbonate, polyethylene, polymethyl methacrylate, glass fiber reinforced plastic or steel.
Further, the number of unit cell structures is M multiplied by N, wherein M and N are any integer larger than 2.
Furthermore, the panel, the bilateral acoustic black hole embedded plate and the back plate are all made of photosensitive resin materials or aluminum alloys.
Compared with the prior art, the invention has the following improvement effects:
1. the invention has better isolation and inhibition effects on the low-frequency and middle-frequency noise of a broadband noise source by adopting a multilayer structure, and the specific realization principle is as follows: the phononic crystal is a recently emerging periodic structure, when an elastic wave propagates in the structure, the periodic structure can inhibit wave propagation in certain frequency ranges, the frequency ranges are called band gaps, vibration of the structure can be effectively inhibited by designing geometric and physical parameters of the periodic structure, and the periodic structure has good reliability and designability. The acoustic black hole structure utilizes the energy focusing principle of bending waves, and the propagation speed of the bending waves transmitted into the structure can be gradually attenuated to zero by designing the thickness dimension of the acoustic black hole structure, so that the suppression of the bending waves of the structure can be realized, and the suppression of the vibration and the noise of the structure can be realized. The invention adopts a passive vibration reduction and noise reduction method, and can realize the purpose of inhibiting the vibration of the structure by applying a vibration reduction and isolation system on a vibration source and a propagation path thereof.
2. The sandwich plate structure is constructed by introducing the orthogonal reinforced rib beams, so that the integral rigidity of the structure can be effectively improved, and the sandwich plate structure has excellent structural strength while meeting the sound insulation capability.
3. The composite sandwich flat plate structure has the advantages of economy, durability, reliable performance, low cost, long service life, difficult deformation, no pollution to the environment and the like, and has higher application value.
Drawings
Fig. 1 is an isometric view of the present invention. Fig. 2 is an isometric view of the panel 1. Fig. 3 is an isometric view of a double-sided acoustic black hole insertion plate 2. Fig. 4 is an isometric view of the back plate 3. Fig. 5 is a front view of fig. 1.
Detailed Description
The first embodiment is as follows: the embodiment is described by combining fig. 1 to fig. 5, and the acoustic black hole sandwich flat plate vibration attenuation structure of the embodiment comprises a panel 1, a bilateral acoustic black hole embedded plate 2 and a back plate 3, wherein the panel 1 and the back plate 3 are both square plates, an orthogonal reinforcing plate 4 is arranged on one side plane of the panel 1 and the back plate 3, a plurality of cavities 7 are arranged in the orthogonal reinforcing plate 4, a plurality of acoustic black holes 5 are embedded in the upper side surface and the lower side surface of the bilateral acoustic black hole embedded plate 2, a cut-off hole 6 is arranged at the thinnest position of the acoustic black hole 5 in the thickness direction, the panel 1, the bilateral acoustic black hole embedded plate 2 and the back plate 3 are fixedly connected in sequence from top to bottom, each acoustic black hole 5 on the bilateral acoustic black hole embedded plate 2 is embedded into one cavity 7, and the acoustic black hole 5 embedded into the cavity 7 is of a single cell structure.
The phononic crystal is a periodic structure which is recently developed, the vibration of the structure can be effectively inhibited by utilizing a frequency forbidden band mechanism of the periodic structure and designing geometric and physical parameters of the periodic structure, and the vibration inhibition mode belongs to the passive control category and has better reliability and designability. The acoustic black hole structure utilizes the energy focusing principle of bending waves, and the propagation speed of the bending waves transmitted into the structure can be gradually attenuated to zero by designing the thickness dimension of the acoustic black hole structure, so that the suppression of the bending waves of the structure can be realized, and the suppression of the vibration and the noise of the structure can be realized.
The second embodiment is as follows: the present embodiment will be described with reference to fig. 2 and 4, in which the front plate 1 and the rear plate 3 are both square flat plates, and the cavity 7 is a square cavity. By the arrangement, the single acoustic black hole is formed by rotating the one-dimensional acoustic black hole and has good symmetry, so that the corresponding panel and the corresponding cavity are designed to be square, and the excellent structural strength of the whole structure is ensured. Other components and connections are the same as in the first embodiment.
The third concrete implementation mode: referring to fig. 1, the front panel 1, the bilateral acoustic black hole embedded plate 2 and the back panel 3 of the present embodiment are fixedly connected by gluing or welding in sequence from top to bottom; or the panel 1, the bilateral acoustic black hole embedded plate 2 and the back plate 3 are integrally formed by 3D printing in the sequence from top to bottom. So set up, can guarantee overall structure's stability, when size, the material parameter control frequency band gap position through adjusting the structure, ensure that the experimental result can satisfy actual need. Other compositions and connections are the same as in the first or second embodiments.
The fourth concrete implementation mode: referring to fig. 2 and 4, the thickness of the front plate 1 and the back plate 3 of the present embodiment is 1mm to 5mm, the rib height of the orthogonal rib plate 4 is 5mm to 30mm, and the rib thickness is 1mm to 5 mm. According to the arrangement, the size selection of the sandwich plate structure is related to the sound insulation and noise reduction performance of the sandwich plate structure, and in a low-frequency range, the thicker the panel thickness and the rib beam thickness are, the smaller the rib beam height is, and the better the sound insulation performance of the structure is; the smaller the thickness of the panel and the height of the rib beam are, the thicker the rib beam is, and the better the vibration damping performance of the structure is. Other compositions and connection relationships are the same as in the first, second or third embodiment.
The fifth concrete implementation mode: the present embodiment will be described with reference to fig. 2 and 4, and the material of the face plate 1 and the back plate 3 of the present embodiment is polyvinyl chloride, polypropylene, polycarbonate, polyethylene, polymethyl methacrylate, glass fiber reinforced plastic, or steel. With the arrangement, if the panel 1 and the back plate 3 are made of steel, the acoustic black hole embedded plate 2 on both sides is also made of metal, the fixed connection mode of the panel 1 and the back plate 3 on the acoustic embedded plate 2 is welding, and the specific material and size are determined by actual working conditions. Other compositions and connection relationships are the same as those in the first, second, third or fourth embodiment.
The sixth specific implementation mode: the present embodiment is described with reference to fig. 2, and the thickness of the double-sided acoustic black hole insertion plate 2 of the present embodiment is 5mm to 20 mm. With the arrangement, the strength of the sandwich structure and the working environment are considered, and the thicker the embedded plate is, the higher the overall structural strength can be improved, which depends on the limiting condition of the total thickness. Other compositions and connection relationships are the same as in the first, second, third, fourth or fifth embodiment.
The seventh embodiment: the present embodiment is described with reference to fig. 2, and the present embodiment further defines the cut-off hole 6 of the double-sided acoustic black hole insertion plate 2 in the sixth embodiment, and the thickness of the cut-off hole 6 is 0.5mm to 2 mm. According to the arrangement, the thickness of the cut-off hole is related to the sound insulation and noise reduction performance of the sandwich panel structure, the smaller the cut-off thickness 6 of the acoustic black hole 5 is, the better the sound insulation performance of the sandwich panel structure is, and the thickness of the sandwich panel structure is determined according to the actual processing conditions. Other components and connection relations are the same as those of any one of the first to sixth embodiments.
The specific implementation mode is eight: referring to fig. 1, the present embodiment will be described, and the material of the double-sided acoustic black hole insertion plate 2 of the present embodiment is polyvinyl chloride, polypropylene, polycarbonate, polyethylene, polymethyl methacrylate, glass fiber reinforced plastic, or steel. With this arrangement, if the material of the dual-sided acoustic black hole embedded plate 2 is steel, and the material of the face plate 1 and the back plate 3 is also metal, the fixing manner of the acoustic embedded plate 2 and the face plate 1 and the back plate 3 is welding, and the specific material and size thereof should be determined by the actual working conditions. Other constitutions and connection relationships are the same as those of any one of the first to seventh embodiments.
The specific implementation method nine: referring to fig. 1, the number of unit cell structures in the present embodiment is M multiplied by N, where M and N are arbitrary integers greater than 2. So set up, overall structure can make reasonable the change to the requirement of structural shape according to the operational environment that is located on the basis that satisfies periodic condition, and the cycle number of structure is more, and the damping noise reduction effect is more obvious. Other compositions and connection relations are the same as those of any one of the first to eighth embodiments.
The specific implementation mode is ten: referring to fig. 1 to 5, the present embodiment will be described, in which the front panel 1, the double-sided acoustic black hole insertion plate 2, and the rear panel 3 are made of a photosensitive resin material or an aluminum alloy. With the arrangement, the requirement of the actual working environment of the flat plate structure on the load bearing capacity of the vibration damping structure is considered, and if the load bearing capacity requirement of the vibration damping structure is low, a light material can be considered. Other components and connection relationships are the same as those in any one of the first to ninth embodiments.
The working principle of the invention is explained in conjunction with fig. 1 to 5:
in the use process of the invention, when the sound wave is transmitted through the sandwich flat plate structure, the sound wave is divided into three parts, wherein one part is energy reflected by the panel 1, the other part is energy transmitted through the panel 3, and the third part is energy absorbed in the flat plate structure. Wherein, one part of the absorbed energy is that the transmission of vibration and sound in the forbidden band range is blocked by the frequency forbidden band characteristic of the periodic structure, and the position of the frequency forbidden band (frequency band gap) can be controlled by adjusting the size and the material parameters of the structure; another part is that when the sound wave is incident on the surface of the acoustic black hole 5, the varying thickness deflects the propagation direction of the bending wave, concentrating it in the central region 6 of the acoustic black hole. Meanwhile, as the thickness of the plate is reduced, the wave velocity is also gradually reduced and an energy focusing effect is generated at the boundary where the thickness is minimum, thereby achieving energy absorption and vibration suppression.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (10)
1. The utility model provides an acoustics black hole core plate damping structure, it includes panel (1) and backplate (3), its characterized in that: it still includes two side acoustics black hole embedding board (2), panel (1) and backplate (3) are square plate, and all be equipped with quadrature stiffened plate (4) on the one side plane of panel (1) and backplate (3), have a plurality of cavitys (7) in quadrature stiffened plate (4), all imbed a plurality of acoustics black hole (5) on two upper and lower sides of two side acoustics black hole embedding board (2), and cut hole (6) are seted up to thinnest position department on acoustics black hole (5) thickness, panel (1), two side acoustics black hole embedding board (2) and backplate (3) are according to order fixed connection from top to bottom, and every acoustics black hole (5) on two side acoustics black hole embedding board (2) imbed in one cavity (7), acoustics black hole (5) of embedding in cavity (7) are a unit cell structure.
2. The acoustic black hole sandwich panel vibration damping structure of claim 1, wherein: the panel (1) and the back plate (3) are both square flat plates, and the cavity (7) is a square cavity.
3. The acoustic black hole sandwich panel vibration damping structure of claim 2, wherein: the panel (1), the bilateral acoustic black hole embedded plate (2) and the back plate (3) are fixedly connected in sequence from top to bottom in an adhesive or welding mode; or the panel (1), the bilateral acoustic black hole embedded plate (2) and the back plate (3) are integrally formed by 3D printing in the sequence from top to bottom.
4. The acoustic black hole sandwich panel vibration damping structure of claim 3, wherein: the thickness of the face plate (1) and the back plate (3) is 1mm-5mm, the height of the rib beam of the orthogonal reinforcing plate (4) is 5mm-30mm, and the thickness of the rib beam is 1mm-5 mm.
5. The acoustic black hole sandwich panel vibration damping structure of claim 4, wherein: the material of the face plate (1) and the back plate (3) is polyvinyl chloride, polypropylene, polycarbonate, polyethylene, polymethyl methacrylate, glass fiber reinforced plastic or steel.
6. The acoustic black hole sandwich panel vibration damping structure of claim 5, wherein: the thickness of the double-side acoustic black hole embedded plate (2) is 5mm-20 mm.
7. The acoustic black hole sandwich panel vibration damping structure of claim 6, wherein: the thickness of the cutting hole (6) is 0.5mm-2 mm.
8. The acoustic black hole sandwich panel vibration damping structure of claim 7, wherein: the material of the double-side acoustic black hole embedded plate (2) is polyvinyl chloride, polypropylene, polycarbonate, polyethylene, polymethyl methacrylate, glass fiber reinforced plastic or steel.
9. The acoustic black hole sandwich panel damping structure of claim 1 or 8, wherein: the number of unit cell structures is M multiplied by N, wherein M and N are any integer larger than 2.
10. The acoustic black hole sandwich panel vibration damping structure of claim 1, wherein: the panel (1), the bilateral acoustic black hole embedded plate (2) and the back plate (3) are all made of photosensitive resin materials or aluminum alloys.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112652287B (en) * | 2020-12-15 | 2022-06-03 | 哈尔滨工程大学 | Acoustic black hole sandwich panel vibration reduction structure |
| CN112581928B (en) * | 2020-12-15 | 2022-09-02 | 哈尔滨工程大学 | Acoustic black hole periodic sandwich beam structure for noise reduction |
| CN113658573B (en) * | 2021-08-24 | 2023-07-14 | 东北大学 | Spiral two-dimensional acoustic black hole vibration isolation and noise reduction structure |
| CN113628602B (en) * | 2021-08-26 | 2023-07-04 | 东北大学 | Hexagonal periodic acoustic black hole vibration and noise reduction structure |
| CN114623181B (en) * | 2022-03-03 | 2024-08-30 | 中国铁路南宁局集团有限公司 | Adsorption type periodic acoustic black hole damper for vibration control of switch rail |
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