Multi-vibrator acoustic black hole broadband vibration absorber with power law distribution and design method of multi-vibrator acoustic black hole broadband vibration absorber

Abstract

The design method comprises the steps that physical parameters of an acoustic black hole vibration absorption beam, a connecting piece and an outer frame are set, geometric parameters and power law indexes of a one-dimensional acoustic black hole structure are determined, the radius of an acoustic black hole area is calculated according to the upper limit and the lower limit of the vibration reduction target frequency, and the multi-vibrator acoustic black hole broadband vibration absorber with the power law distribution is obtained. The number and the arrangement mode of the vibration absorption beams are determined by combining the width of the one-dimensional acoustic black hole structure and the geometric dimension of the connecting piece; through the design of a power law curve, it is ensured that the vibration absorber has an excellent vibration absorption effect on vibration in a broadband range; the broadband vibration damper can be embedded or additionally used in a vibration damping target structure, is high in adaptability and has efficient broadband vibration damping performance; and moreover, resonance points can be effectively avoided, the vibration reduction frequency band is widened, and the method is suitable for a complex multi-frequency vibration environment.

Description

Technical Field

[0001] The present invention relates to the technical field of acoustic black holes, and in particular to a power-law distributed multi-oscillator acoustic black hole broadband vibration absorber and a design method thereof. Background Art

[0002] In the past decade, acoustic black holes have attracted widespread attention because of their wide-band and high-efficiency wave focusing, simple and flexible implementation methods, and obvious advantages in applications such as vibration and noise reduction of thin-walled structures and energy recovery.

[0003] According to existing research, acoustic black holes can effectively reduce the propagation speed of bending waves in the structure by changing the local thickness, reduce the reflection of bending waves from the structure boundary, and form an area with high energy density, thereby achieving the purpose of structural vibration reduction.

[0004] After checking, it was found that the Chinese invention patent with patent number "2023102233931" discloses a design method for a tree-shaped acoustic black hole dynamic vibration absorber. The scheme is based on the principle of acoustic black holes. By vertically stacking bidirectional acoustic black hole vibration absorbing beams of the same size, a tree-shaped acoustic black hole dynamic vibration absorber containing multiple acoustic black hole units is designed. The invention superimposes different numbers of bidirectional acoustic black hole vibration absorbing beams to form a tree-shaped acoustic black hole vibration absorber, thereby achieving wide-band vibration reduction for the vibration reduction target. However, the invention superimposes bidirectional acoustic black hole vibration absorbing beams in the vertical direction to form a tree-shaped acoustic black hole vibration absorber, which has high requirements for practical space and does not conform to the use scenarios with relatively limited space. The use scenarios and scope are greatly restricted. Moreover, superimposing the same bidirectional acoustic black hole vibration absorbing beams to form a tree-shaped acoustic black hole vibration absorber is very limited in widening the low-frequency vibration reduction band of the acoustic black hole vibration absorber, and the expected vibration reduction effect cannot be achieved. Summary of the invention

[0005] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0006] In view of the above existing problems, the present invention is proposed. Therefore, the present invention provides a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber and a design method thereof, which is used to solve the technical problem that the low-frequency vibration reduction effect is not obvious and the use scenarios are extremely limited in the background technology.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: a power-law distributed multi-oscillator acoustic black hole broadband vibration absorber, comprising:

[0008] Acoustic black hole vibration absorbing beams, connectors and outer frames;

[0009] The acoustic black hole vibration absorbing beam is composed of four one-dimensional acoustic black hole structures and arranged in an equidistant manner;

[0010] Each acoustic black hole region in the one-dimensional acoustic black hole structure is obtained by a power law curve formula, and each acoustic black hole region is damped and pasted to the surface of the one-dimensional acoustic black hole structure to which the acoustic black hole region belongs by an adhesive;

[0011] The radius length of the acoustic black hole region decreases from the middle to both sides according to a power rate curve formula, and the acoustic black hole vibration absorbing beam is connected to the outer frame through a connecting piece.

[0012] As a preferred solution of the power-law distributed multi-vibrator acoustic black hole broadband vibration absorber described in the present invention, it also includes:

[0013] The one-dimensional acoustic black hole structure is assembled by welding;

[0014] The acoustic black hole vibration absorbing beam is connected to the outer frame by welding through a connecting piece;

[0015] The adhesive includes epoxy resin glue, styrene-butadiene rubber and cyanoacrylate glue;

[0016] The acoustic black hole vibration absorbing beam is produced by integrated casting or 3D printing.

[0017] A design method for a power-law distributed multi-oscillator acoustic black hole broadband vibration absorber, comprising:

[0018] Set the physical parameters of the acoustic black hole vibration absorbing beam, connectors, outer frame and damping;

[0019] Setting the power law index and the geometric parameters of the one-dimensional acoustic black hole structure;

[0020] According to the upper and lower limits of the vibration reduction target frequency range, the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest and shortest acoustic black hole vibration absorbing beams within the upper and lower limits and the power law curve of the acoustic black hole region are obtained respectively;

[0021] Based on the width of the one-dimensional acoustic black hole structure, the geometric dimensions of the connector are determined;

[0022] Calculating the length difference between the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest and shortest acoustic black hole vibration absorbing beams, and setting the number of acoustic black hole vibration absorbing beams according to the length difference, and obtaining the distance of the equidistant arrangement between the longest and shortest acoustic black hole vibration absorbing beams based on the width of the one-dimensional acoustic black hole structure and the geometric dimensions of the connecting parts;

[0023] The power law index is set, and the polynomial coefficient of the power law curve of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest acoustic black hole vibration absorbing beam is determined according to the distance of the equidistant arrangement between the longest and shortest acoustic black hole vibration absorbing beams and the length difference of the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest and shortest acoustic black hole vibration absorbing beams;

[0024] According to the power law curve of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest acoustic black hole vibration absorbing beam, the length of the acoustic black hole region in the one-dimensional acoustic black hole structure in the middle acoustic black hole vibration absorbing beam is determined. At the same time, combined with the geometric parameters of the one-dimensional acoustic black hole structure, the structural design of the remaining acoustic black hole vibration absorbing beams is completed.

[0025] As a preferred solution of the design method of the power-law distributed multi-vibrator acoustic black hole broadband vibration absorber described in the present invention, the physical parameters of the acoustic black hole vibration absorbing beam, the connecting member, the outer frame and the damping are set, including:

[0026] Setting the joint material parameters of the acoustic black hole vibration absorbing beam, the connecting member and the outer frame, wherein the joint material parameters include elastic modulus E1, Poisson's ratio v1, loss factor η1 and density ρ1;

[0027] The damping parameters are set, and the damping parameters include elastic modulus E2, Poisson's ratio v2, loss factor η2 and density ρ2.

[0028] As a preferred solution of the method for designing a power-law distributed multi-oscillator acoustic black hole broadband vibration absorber described in the present invention, the power-law index and the geometric parameters of the one-dimensional acoustic black hole structure are set, including:

[0029] Set the power law m;

[0030] The thickness h1 of the uniform part, the cutoff thickness h2, the width x and the length R0 of the uniform part of the one-dimensional acoustic black hole structure are set to obtain the damping thickness h0.

[0031] As a preferred solution of the method for designing a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber described in the present invention, the power-law curve of the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest and shortest acoustic black hole vibration absorbing beams within the upper and lower limits and the acoustic black hole region is obtained according to the upper and lower limits of the target frequency range of vibration reduction, respectively, including:

[0032] According to the lower limit f1 of the lowest frequency range of the vibration reduction target, the radius R1 of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest acoustic black hole vibration absorbing beam is obtained. Combined with the geometric parameters of the one-dimensional acoustic black hole structure, the polynomial coefficient ε1 in the power law curve is determined to obtain the power law curve of the longest acoustic black hole region.

[0033] According to the upper limit f2 of the lowest frequency range of the vibration reduction target, the radius R2 of the acoustic black hole region in the one-dimensional acoustic black hole structure in the shortest acoustic black hole vibration absorbing beam is obtained. Combined with the geometric parameters of the one-dimensional acoustic black hole structure, the polynomial coefficient ε2 in the power law curve is determined to obtain the power law curve of the shortest acoustic black hole region.

[0034] As a preferred solution of the design method of the power-law distributed multi-vibrator acoustic black hole broadband vibration absorber described in the present invention, the geometric dimensions of the connecting piece are determined based on the width of the one-dimensional acoustic black hole structure, including:

[0035] The geometrical dimensions of the connecting element include the length t and the width Δt of the connecting element.

[0036] As a preferred solution of the design method of the power-law distributed multi-oscillator acoustic black hole broadband vibration absorber described in the present invention, wherein: the length difference between the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest and shortest acoustic black hole vibration absorbing beams is calculated, and the number of acoustic black hole vibration absorbing beams is set according to the length difference, and based on the width of the one-dimensional acoustic black hole structure and the geometric dimensions of the connecting parts, the distance between the longest and shortest acoustic black hole vibration absorbing beams in an equidistant arrangement is obtained, including:

[0037] The length difference ΔR between the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest acoustic black hole vibration absorbing beam and the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure in the shortest acoustic black hole vibration absorbing beam is obtained by calculation;

[0038] The number y of the acoustic black hole vibration absorbing beams between the longest acoustic black hole vibration absorbing beam and the shortest acoustic black hole vibration absorbing beam is set, and the distance Δx of the equidistant arrangement between the shortest acoustic black hole vibration absorbing beam and the longest acoustic black hole vibration absorbing beam is calculated based on the width x of the acoustic black hole vibration absorbing beam and the length t of the connecting part.

[0039] As a preferred solution of the design method of the power-law distributed multi-oscillator acoustic black hole broadband vibration absorber described in the present invention, wherein: the power-law index is set, and the polynomial coefficients of the power-law curve of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest acoustic black hole vibration absorbing beam are determined according to the distance of the equidistant arrangement between the longest and shortest acoustic black hole vibration absorbing beams and the length difference of the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest and shortest acoustic black hole vibration absorbing beams, including:

[0040] According to the ΔR and Δx, a power law curve is determined in which the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest acoustic black hole vibration absorbing beam decreases toward both sides of the radius. The polynomial coefficients in .

[0041] As a preferred solution of the method for designing a power-law distributed multi-oscillator acoustic black hole broadband vibration absorber described in the present invention, the length of the acoustic black hole region in the one-dimensional acoustic black hole structure in the middle acoustic black hole vibration absorbing beam is determined according to the power-law curve of the acoustic black hole region in the one-dimensional acoustic black hole structure in the longest acoustic black hole vibration absorbing beam, and the structural design of the remaining acoustic black hole vibration absorbing beams is completed in combination with the geometric parameters of the one-dimensional acoustic black hole structure, including:

[0042] According to the distance and size of each acoustic black hole vibration absorbing beam, the length a, width b and frame width Δb, Δa of the outer frame are set;

[0043] In the uniform thickness area of ​​the acoustic black hole vibration absorbing beam, it is connected with the other acoustic black hole vibration absorbing beams and the outer frame through connecting parts to complete the design of the power-law distribution acoustic black hole vibration absorber.

[0044] Compared with the prior art, the invention has the following beneficial effects:

[0045] 1. The present invention controls the size of the acoustic black hole region of the one-dimensional acoustic black hole structure through a power law curve, and calculates the acoustic black hole region radii of the longest and shortest acoustic black hole structures respectively according to the upper and lower frequency ranges of the vibration reduction target, thereby ensuring that vibration absorbing beams of different sizes can work together, effectively avoiding the resonance point, and achieving broadband vibration reduction;

[0046] 2. By calculating the size and distance of each acoustic black hole vibration-absorbing beam, the length and width of the outer frame are obtained, so that the solution of the present invention can flexibly adapt to structures of different sizes and shapes, greatly improving the space utilization rate; whether embedded in a larger plate or attached to an external structure, the number and size of the vibration-absorbing beams can be dynamically optimized according to space requirements, solving the problem of traditional vibration absorbers in scenarios with space limitations;

[0047] 3. By calculating the distance between the shortest and longest acoustic black hole vibration-absorbing beams according to the width of the one-dimensional acoustic black hole structure and the length and width of the connecting parts, multiple vibration-absorbing beams can be superimposed on each other in terms of vibration-absorbing performance, greatly enhancing the overall vibration-absorbing effect and avoiding the limitations of a single vibration-absorbing beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0049] Figure 1 This is an overall flow chart of a method for designing a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to an embodiment of the present invention;

[0050] Figure 2 It is an isometric view of the acoustic black hole vibration absorbing beam structure of the power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to one embodiment of the present invention;

[0051] Figure 3 A front view of the acoustic black hole vibration absorbing beam structure of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to an embodiment of the present invention;

[0052] Figure 4 An isometric view of a power-law distributed acoustic black hole vibration absorber of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to an embodiment of the present invention;

[0053] Figure 5 A top view of a power-law distributed acoustic black hole vibration absorber of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to an embodiment of the present invention;

[0054] Figure 6 A homogeneous single plate axonometric diagram of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to an embodiment of the present invention;

[0055] Figure 7 An isometric view of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber embedded in a plate according to an embodiment of the present invention;

[0056] Figure 8 A diagram of the acceleration admittance level of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber embedded in a plate according to an embodiment of the present invention;

[0057] Fig. 9 It is an isometric view of a power-law distributed acoustic black hole absorber additional plate of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to an embodiment of the present invention;

[0058] Fig.10 This is a diagram of the acceleration admittance level on the additional plate of the power-law distributed acoustic black hole absorber of the power-law distributed multi-oscillator acoustic black hole broadband vibration absorber described in one embodiment of the present invention. DETAILED DESCRIPTION

[0059] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0060] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0061] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0062] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0063] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0064] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0065] Example 1

[0066] Reference Figure 1 , which is the first embodiment of the present invention, provides a method for designing a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber, comprising:

[0067] S1, setting the physical parameters of the acoustic black hole vibration absorbing beam 1, the connecting member 2, the outer frame 3 and the damping 12;

[0068] Further, the joint material parameters of the acoustic black hole vibration absorbing beam 1, the connecting member 2 and the outer frame 3 are set, and the joint material parameters include elastic modulus E1, Poisson's ratio v1, loss factor η1 and density ρ1;

[0069] Further, the parameters of the damping 12 are set, and the parameters of the damping 12 include elastic modulus E2, Poisson's ratio v2, loss factor η2 and density ρ2;

[0070] S2, setting the power law index and the geometric parameters of the one-dimensional acoustic black hole structure 11;

[0071] Furthermore, the power law m is set;

[0072] Specifically, the value range of the power law m is (2, 2.5);

[0073] Further, the thickness h1 of the uniform part, the cut-off thickness h2, the width x and the length R0 of the uniform part of the one-dimensional acoustic black hole structure 11 are set to obtain the thickness h0 of the damping 12;

[0074] Preferably, h2 is 0.5 to 1 times of h0;

[0075] S3. According to the upper and lower limits of the vibration reduction target frequency range, respectively obtain the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in the longest and shortest acoustic black hole vibration absorbing beam 1 within the upper and lower limits and the power law curve of the acoustic black hole region;

[0076] It needs to be explained that the wavelength and propagation characteristics of vibrations at different frequencies are different. Therefore, by calculating the radius of the acoustic black hole region at different frequencies, the power law curve can be adjusted to adapt to vibrations of different frequencies. For example, for low-frequency vibrations, the wavelength is longer, and the acoustic black hole region requires a larger radius to achieve effective wave gathering and energy dissipation; for high-frequency vibrations, the wavelength is shorter, and the corresponding acoustic black hole region radius is smaller.

[0077] Further, according to the lower limit f1 of the lowest frequency range of the vibration reduction target, the radius R1 of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in the longest acoustic black hole vibration absorbing beam 1 is obtained, and the polynomial coefficient ε1 in the power law curve is determined in combination with the geometric parameters of the one-dimensional acoustic black hole structure 11, and the power law curve of the longest acoustic black hole region is obtained;

[0078] Specifically, the radius R1 of the acoustic black hole region is expressed as:

[0079]

[0080] Specifically, the power law curve of the longest acoustic black hole region is expressed as:

[0081]

[0082] Further, according to the upper limit f2 of the lowest frequency range of the vibration reduction target, the radius R2 of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in the shortest acoustic black hole vibration absorbing beam 1 is obtained, and the polynomial coefficient ε2 in the power law curve is determined in combination with the geometric parameters of the one-dimensional acoustic black hole structure 11, and the power law curve of the shortest acoustic black hole region is obtained;

[0083] Specifically, the radius R2 of the acoustic black hole region is expressed as:

[0084]

[0085] Specifically, the power law curve of the shortest acoustic black hole region is expressed as:

[0086]

[0087] S4. Determine the geometric dimensions of the connector 2 based on the width of the one-dimensional acoustic black hole structure 11;

[0088] Specifically, the geometric dimensions of the connecting member 2 include the length t and the width Δt of the connecting member;

[0089] Preferably, the length t of the connecting member is 3 to 5 times the width x of the acoustic black hole vibration absorbing beam, and the width Δt of the connecting member is equal to the width x of the acoustic black hole vibration absorbing beam;

[0090] S5. Calculate the length difference between the longest and shortest acoustic black hole vibration absorbing beams 1 and the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure 11, and set the number of acoustic black hole vibration absorbing beams 1 according to the length difference, and obtain the distance between the longest and shortest acoustic black hole vibration absorbing beams in an equidistant arrangement based on the width of the one-dimensional acoustic black hole structure 11 and the geometric dimensions of the connector 2;

[0091] Furthermore, the length difference ΔR between the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in the longest acoustic black hole vibration absorbing beam 1 and the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in the shortest acoustic black hole vibration absorbing beam 1 is obtained by calculation;

[0092] Furthermore, the number y of the acoustic black hole vibration absorbing beams 1 between the longest acoustic black hole vibration absorbing beam 1 and the shortest acoustic black hole vibration absorbing beam 1 is set, and the distance Δx of the equidistant arrangement between the shortest acoustic black hole vibration absorbing beam 1 and the longest acoustic black hole vibration absorbing beam 1 is calculated according to the width x of the acoustic black hole vibration absorbing beam 1 and the length t of the connecting member 2;

[0093] It should be noted that by equidistantly arranging the black hole vibration-absorbing beams and designing the radius difference, a decreasing sound wave propagation path can be formed, so that the vibration wave is gradually dissipated on each vibration-absorbing beam, and it is avoided that the vibration energy is concentrated too much on a certain vibration-absorbing beam, thereby generating resonance, thereby ensuring the good adaptability of the vibration absorber to vibrations of different frequencies;

[0094] S6. Setting a power law index, and determining the polynomial coefficient of the power law curve of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in the longest acoustic black hole vibration absorbing beam 1 according to the distance between the longest and shortest acoustic black hole vibration absorbing beams 1 in the equidistant arrangement and the length difference between the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in the longest and shortest acoustic black hole vibration absorbing beams 1;

[0095] Further, according to ΔR and Δx, a power law curve is determined in which the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in the longest acoustic black hole vibration absorbing beam 1 decreases toward both sides of the radius. The polynomial coefficients in ;

[0096] Preferably, the power law exponents n and m have the same value;

[0097] It should be noted that by introducing the polynomial coefficients of the power law curve, the radius reduction curve of the acoustic black hole region of the vibration absorbing beam can be accurately adjusted to ensure that the vibration absorbing capacity of the vibration absorber at different frequencies is maximized; on the one hand, the problem that the traditional vibration absorber can only reduce vibration at a specific frequency is avoided; on the other hand, the design of the power law curve enables the vibration absorber to have a wide frequency band vibration reduction capability, especially in the low frequency band.

[0098] S7. According to the power law curve of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in the longest acoustic black hole vibration absorbing beam 1, the length of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in the middle acoustic black hole vibration absorbing beam 1 is determined, and at the same time, the geometric parameters of the one-dimensional acoustic black hole structure 11 are combined to complete the structural design of the remaining acoustic black hole vibration absorbing beams 1;

[0099] Furthermore, the length a, width b and frame widths Δb and Δa of the outer frame 3 are set according to the distance and size of each acoustic black hole vibration absorbing beam 1;

[0100] Furthermore, in the uniform thickness area of ​​the acoustic black hole vibration absorbing beam 1, it is connected with the other acoustic black hole vibration absorbing beams 1 and the outer frame 3 through the connecting piece 2 to complete the design of the power-law distribution acoustic black hole vibration absorber.

[0101] Example 2

[0102] Reference Figures 2 to 5 , which is the first embodiment of the present invention, and provides a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber, comprising:

[0103] refer to Figure 2 The acoustic black hole vibration absorbing beam 1 includes a one-dimensional acoustic black hole structure 11 and a damper 12. The acoustic black hole vibration absorbing beam 1 is composed of four one-dimensional acoustic black hole structures 11 welded together; the damper 12 covers half of the acoustic black hole region of the acoustic black hole vibration absorbing beam 1. The basic power law curve of the acoustic black hole region in the acoustic black hole vibration absorbing beam 1 conforms to the following formula:

[0104]

[0105] refer to Figure 3 , the total length of the acoustic black hole vibration absorbing beam 1 is 2R=2(R0+R1);

[0106] refer to Figure 4 and Figure 5 , the width of the acoustic black hole vibration absorbing beam 1 is x, and the acoustic black hole vibration absorbing beams 1 are connected by two connecting pieces 2 through welding, the length of the connecting piece 2 is t=3x, and the width is Δt=2R0. The acoustic black hole vibration absorbing beam 1 is welded to the outer frame 3 through the connecting piece 2, and at this time, the length of the connecting piece 2 between the acoustic black hole vibration absorbing beam 1 and the outer frame 3 is t / 3; the thickness of the outer frame 3 and the connecting piece 2 is d, especially d=2h1; the length of the outer frame 3 is b, the width is a, and the width is Δb=Δa. The middle acoustic black hole vibration absorbing beam 1 is the acoustic black hole vibration absorbing beam 1 with the longest length, and the two sides are acoustic black hole vibration absorbing beams 1 with gradually decreasing length and equidistant arrangement. The acoustic black hole area radius of the longest acoustic black hole vibration absorbing beam 1 and the acoustic black hole area radius of the shortest acoustic black hole vibration absorbing beam 1 decrease according to a power law, and the power law curve is as follows:

[0107]

[0108] Example 3

[0109] Reference Figures 6 to 10 , which is the third embodiment of the present invention, and this embodiment provides a method for designing a power-law distributed multi-oscillator acoustic black hole broadband vibration absorber, comprising: further analyzing the scheme of the present invention through simulation experiments;

[0110] The materials of the acoustic black hole vibration absorbing beam 1, the connecting member 2 and the outer frame 3 are set to be metal aluminum, and the damping is butyl rubber. The material parameters are shown in Table 1 below;

[0111] Table 1

[0112]

[0113]

[0114] The power law m=2, the uniform part thickness h1=0.005m, the cutoff thickness h2=0.0005m, the width x=0.005m and the length R0=0.005m of the uniform part of the one-dimensional acoustic black hole structure 11, and the damping thickness h0=0.00025m are obtained;

[0115] According to the lower limit of the target lowest frequency range of vibration reduction f1 = 75Hz, the length of the acoustic black hole region in the longest one-dimensional acoustic black hole structure 11 is determined to be R1 = 0.015m, and the polynomial coefficients of the function can be calculated. The power law curve of the acoustic black hole region in the longest one-dimensional acoustic black hole structure 11 is:

[0116]

[0117] According to the upper limit of the target lowest frequency range of vibration reduction f2 = 160 Hz, the acoustic black hole region length R1 = 0.007 m in the shortest one-dimensional acoustic black hole structure 11 is determined, and the polynomial coefficients of the function can be calculated. The power law curve of the acoustic black hole region in the shortest one-dimensional acoustic black hole structure 11 is:

[0118]

[0119] Therefore, the length difference between the acoustic black hole regions of the shortest one-dimensional acoustic black hole structure 11 and the longest one-dimensional acoustic black hole structure 11 is ΔR=0.008m;

[0120] The number of acoustic black hole vibration absorbing beams 1 between the shortest one-dimensional acoustic black hole structure 11 and the longest one-dimensional acoustic black hole structure 11 is set to y=3, and the distance Δx between the shortest one-dimensional acoustic black hole structure 11 and the longest one-dimensional acoustic black hole structure 11 is determined to be 0.08m according to the length t=0.015m and the width Δt=0.005m of the connecting member 2;

[0121] According to the length difference ΔR and the distance Δx of the acoustic black hole region of the shortest one-dimensional acoustic black hole structure 11 and the longest one-dimensional acoustic black hole structure 11, the polynomial coefficients are obtained:

[0122] Taking the exponent n = 2, the power law curve of the acoustic black hole region in the longest one-dimensional acoustic black hole structure 11 decreasing in length on both sides is:

[0123]

[0124] According to the power law curve, the length of the acoustic black hole region in the one-dimensional acoustic black hole structure 11 in each of the middle acoustic black hole vibration absorbing beams 1 is determined, and the structural design of the remaining acoustic black hole vibration absorbing beams 1 is completed;

[0125] According to the distance and size of each acoustic black hole vibration absorbing beam 1, the width a=0.04m, the length b=0.18m and the frame width Δb=Δa=0.0025m of the outer frame 3 are set, and the thickness d=0.005m of the outer frame 3 and the connecting member 2;

[0126] like Figure 6 and Figure 7 As shown in the figure, the power-law acoustic black hole absorber is embedded in a homogeneous aluminum plate with a length of 0.3m, a width of 0.16m, and a thickness of 0.005m. A simple harmonic force of 1N is applied to point P1 on the plate. The acceleration at the other end P2 of the plate is extracted and the acceleration admittance level is calculated. The result is as follows: Figure 8 shown by Figure 8 It can be seen that after the power-law distributed acoustic black hole absorber is embedded in the plate, due to the superposition of the vibration reduction effect of multiple oscillators in the power-law distributed acoustic black hole absorber, the vibration suppression of the target lowest frequency band (75Hz~160Hz) is 2~3dB, and for the subsequent frequency band (>160Hz), a better vibration suppression is achieved, and the average vibration suppression reaches 7dB;

[0127] Similarly, if Figure 8 and Fig. 9 As shown, the power-law acoustic black hole absorber is attached to a homogeneous aluminum plate with a length of 0.3 m, a width of 0.16 m, and a thickness of 0.005 m. A simple harmonic force of 1 N is applied to point P1 on the plate. The acceleration at the other end P2 of the plate is extracted and the acceleration admittance level is calculated, as shown in Fig.10 shown by Fig.10 It can be seen that after the power-law distributed acoustic black hole absorber is added to the board, due to the superposition of the vibration reduction effect of multiple oscillators in the power-law distributed acoustic black hole absorber, the vibration suppression of the target lowest frequency band (75Hz~160Hz) is 1~3dB, and for the subsequent frequency band (>160Hz), a better vibration suppression is achieved, and the average vibration suppression reaches 4.5dB;

[0128] In summary, compared with the traditional method, the vibration suppression effect of the solution of the present invention is better, which fully demonstrates the application value of the solution of the present invention in practical scenarios.

[0129] Those skilled in the art will appreciate that the embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program codes. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0130] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0131] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0132] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0133] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0134] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A power-law distributed multi-vibrator acoustic black hole broadband vibration absorber, characterized in that: include: Acoustic black hole vibration absorbing beam (1), connecting member (2) and outer frame (3); The acoustic black hole vibration absorbing beam (1) is composed of four one-dimensional acoustic black hole structures (11) and is arranged in an equidistant manner; Each acoustic black hole region in the one-dimensional acoustic black hole structure (11) is obtained by a power law curve formula, and at the same time, each acoustic black hole region is bonded to the surface of the one-dimensional acoustic black hole structure to which the acoustic black hole region belongs by means of an adhesive to form a damping (12); The radius length of the acoustic black hole region decreases from the middle to both sides according to a power rate curve formula, and the acoustic black hole vibration absorbing beam (1) is connected to the outer frame (3) via a connecting piece (2).

2. The power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to claim 1, characterized in that: Also includes: The one-dimensional acoustic black hole structure (11) is assembled by welding; The acoustic black hole vibration absorbing beam (1) and the outer frame (3) are connected by welding via a connecting piece (2); The adhesive includes epoxy resin glue, styrene-butadiene rubber and cyanoacrylate glue; The acoustic black hole vibration absorbing beam (1) is produced by integrated casting or 3D printing.

3. A method for designing a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber, based on the power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to any one of claims 1 to 2, characterized in that: include: Setting physical parameters of the acoustic black hole vibration absorbing beam (1), the connecting member (2), the outer frame (3) and the damping (12); Setting the power law index and the geometric parameters of the one-dimensional acoustic black hole structure (11); According to the upper and lower limits of the vibration reduction target frequency range, the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest and shortest acoustic black hole vibration absorbing beam (1) within the upper and lower limits and the power law curve of the acoustic black hole region are obtained respectively; Determining the geometric dimensions of the connector (2) based on the width of the one-dimensional acoustic black hole structure (11); Calculating the length difference between the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest and shortest acoustic black hole vibration absorbing beams (1), and setting the number of acoustic black hole vibration absorbing beams (1) according to the length difference, and obtaining the distance between the longest and shortest acoustic black hole vibration absorbing beams in an equidistant arrangement based on the width of the one-dimensional acoustic black hole structure (11) and the geometric dimensions of the connecting member (2); The power law index is set, and the polynomial coefficient of the power law curve of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest acoustic black hole vibration absorbing beam (1) is determined according to the distance of the equidistant arrangement between the longest and shortest acoustic black hole vibration absorbing beams (1) and the length difference of the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest and shortest acoustic black hole vibration absorbing beams (1); According to the power law curve of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest acoustic black hole vibration absorbing beam (1), the length of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the middle acoustic black hole vibration absorbing beam (1) is determined, and at the same time, the geometric parameters of the one-dimensional acoustic black hole structure (11) are combined to complete the structural design of the remaining acoustic black hole vibration absorbing beams (1).

4. The design method of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to claim 3, characterized in that: The physical parameters of the acoustic black hole vibration absorbing beam (1), the connecting member (2), the outer frame (3) and the damping (12) are set, including: Setting the combined material parameters of the acoustic black hole vibration absorbing beam (1), the connecting member (2) and the outer frame (3), wherein the combined material parameters include elastic modulus E1, Poisson's ratio v1, loss factor η1 and density ρ1; The parameters of the damping (12) are set, wherein the parameters of the damping (12) include elastic modulus E2, Poisson's ratio v2, loss factor η2 and density ρ2.

5. The design method of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to claim 4, characterized in that: Setting the power law index and the geometric parameters of the one-dimensional acoustic black hole structure (11) includes: Set the power law m; The thickness h1 of the uniform part, the cut-off thickness h2, the width x and the length R0 of the uniform part of the one-dimensional acoustic black hole structure (11) are set to obtain the thickness h0 of the damping (12).

6. The design method of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to claim 5, characterized in that: According to the upper and lower limits of the vibration reduction target frequency range, the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest and shortest acoustic black hole vibration absorbing beam (1) within the upper and lower limits and the power law curve of the acoustic black hole region are obtained respectively, including: According to the lower limit f1 of the lowest frequency range of the vibration reduction target, the radius R1 of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest acoustic black hole vibration absorbing beam (1) is obtained, and the polynomial coefficient ε1 in the power law curve is determined in combination with the geometric parameters of the one-dimensional acoustic black hole structure (11), thereby obtaining the power law curve of the longest acoustic black hole region; According to the upper limit f2 of the lowest frequency range of the vibration reduction target, the radius R2 of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the shortest acoustic black hole vibration absorbing beam (1) is obtained, and the polynomial coefficient ε2 in the power law curve is determined in combination with the geometric parameters of the one-dimensional acoustic black hole structure (11), thereby obtaining the power law curve of the shortest acoustic black hole region.

7. The design method of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to claim 3 or 6, characterized in that: Based on the width of the one-dimensional acoustic black hole structure (11), the geometric dimensions of the connecting member (2) are determined, including: The geometrical dimensions of the connecting piece (2) include the length t and the width Δt of the connecting piece.

8. The design method of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to claim 7, characterized in that: The length difference between the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest and shortest acoustic black hole vibration absorbing beams (1) is calculated, and the number of the acoustic black hole vibration absorbing beams (1) is set according to the length difference, and the distance between the longest and shortest acoustic black hole vibration absorbing beams in an equidistant arrangement is obtained based on the width of the one-dimensional acoustic black hole structure (11) and the geometric dimensions of the connecting member (2), including: The length difference ΔR between the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest acoustic black hole vibration absorbing beam (1) and the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the shortest acoustic black hole vibration absorbing beam (1) is obtained by calculation; The number y of the acoustic black hole vibration absorbing beams (1) between the longest acoustic black hole vibration absorbing beam (1) and the shortest acoustic black hole vibration absorbing beam (1) is set, and the distance Δx of the equidistant arrangement between the shortest acoustic black hole vibration absorbing beam (1) and the longest acoustic black hole vibration absorbing beam (1) is calculated based on the width x of the acoustic black hole vibration absorbing beam (1) and the length t of the connecting member (2).

9. The design method of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to claim 8, characterized in that: The power law index is set, and the polynomial coefficients of the power law curve of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest acoustic black hole vibration absorbing beam (1) are determined according to the distance of the equidistant arrangement between the longest and shortest acoustic black hole vibration absorbing beams (1) and the length difference of the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest and shortest acoustic black hole vibration absorbing beams (1), including: According to the ΔR and Δx, a power law curve is determined in which the radius of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest acoustic black hole vibration absorbing beam (1) decreases gradually toward both sides of the radius. The polynomial coefficients in 10. The design method of a power-law distributed multi-vibrator acoustic black hole broadband vibration absorber according to claim 9, characterized in that: According to the power law curve of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the longest acoustic black hole vibration absorbing beam (1), the length of the acoustic black hole region in the one-dimensional acoustic black hole structure (11) in the middle acoustic black hole vibration absorbing beam (1) is determined, and the geometric parameters of the one-dimensional acoustic black hole structure (11) are combined to complete the structural design of the remaining acoustic black hole vibration absorbing beams (1), including: According to the distance and size of each acoustic black hole vibration absorbing beam (1), the length a, width b and frame widths Δb and Δa of the outer frame (3) are set; In the uniform thickness area of ​​the acoustic black hole vibration absorbing beam (1), the connecting piece (2) is connected with the other acoustic black hole vibration absorbing beams (1) and the outer frame (3), thereby completing the design of the power-law distribution acoustic black hole vibration absorber.

Images