Multifunctional ultrathin metamaterial design method and device for assembly interface

Abstract

The invention belongs to the technical field of mechanical design, and discloses a multifunctional ultrathin metamaterial design method for an assembly interface, a multifunctional ultrathin metamaterial is arranged on the assembly interface, the multifunctional ultrathin metamaterial comprises two connected layers, and a piezoelectric ceramic sensor is attached to the surface of the first layer of the multifunctional ultrathin metamaterial; the multifunctional ultrathin metamaterial is provided with a two-stage resonance subsystem. The resonance frequency band range of a vibration signal is judged according to the vibration signal collected by the piezoelectric ceramic sensor, and the band gap of the energy band structure of the multifunctional ultra-thin metamaterial covers the resonance frequency band range of the vibration signal by adjusting the two-stage resonance subsystem parameters of the second layer of multifunctional ultra-thin metamaterial, so that the structure of the multifunctional ultra-thin metamaterial is determined. Resonance frequency identification and ultra-wideband vibration isolation of the assembly connection interface can be realized by regulating and controlling the parameters of the multifunctional ultra-thin metamaterial of the assembly interface, the energy loss capacity of the assembly interface is improved, and the dynamic connection performance of all parts of high-end equipment is effectively guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of mechanical design, and more specifically, relates to a multifunctional ultra-thin metamaterial design method and device for assembly interface. Background Art

[0002] Mechanical connection structures are used to connect parts, and their assembly connection performance is a key factor in determining and ensuring the overall performance of mechanical equipment. Mechanical parts are mostly connected by bolts, which are widely used in high-end equipment such as wind power equipment, aerospace, ships and submarines. Currently, the assembly interface performance is improved by finely controlling the assembly interface morphology and hardness and optimizing the assembly connection process.

[0003] However, due to the complex working conditions of the assembly connection interface, such as multiple alternating loads, large gradient temperature-induced vibrations, and multi-band resonances, the energy of the assembly interface accumulates in the relaxation area of ​​the connection interface, resulting in large load strong vibrations and even material damage. At the same time, low-frequency vibrations in the assembly will cause wear, and the chemical environment in which the assembly interface is located is prone to chemical corrosion. However, the current technology for improving the performance of the assembly interface still has many shortcomings, such as high cost and unstable performance. For this reason, strong vibration isolation and vibration reduction of the assembly connection interface in multiple frequency bands and low-frequency and ultra-wide frequency bands under complex service conditions is an effective means to ensure strong assembly connection performance. Due to the limitation of the size of the assembly interface, higher requirements are placed on the size of the vibration isolation metamaterial structure, and it is difficult to coordinate the small-size structure with the low-frequency and ultra-wide-band vibration isolation performance. Summary of the invention

[0004] In order to solve the problem in the prior art that acoustic metamaterials are difficult to apply to assembly interfaces due to size, material and lattice broadband bandgap limitations, the present invention provides a multifunctional ultra-thin metamaterial design method and device for assembly interfaces. The design method integrates the mechanical bearing performance, low-frequency and ultra-wide vibration isolation characteristics, and switching characteristics for assembly interfaces, thereby achieving multi-band and low-frequency and ultra-wide-band vibration isolation of the assembly connection interface of the multifunctional metamaterial structure under complex service conditions.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] A multifunctional ultra-thin metamaterial design method for an assembly interface comprises the following steps:

[0007] The multifunctional ultra-thin metamaterial is arranged on the assembly interface, wherein the multifunctional ultra-thin metamaterial comprises two connected layers, and a piezoelectric ceramic sensor is attached to the surface of the first layer of the multifunctional ultra-thin metamaterial; wherein the multifunctional ultra-thin metamaterial has a two-stage resonator system;

[0008] According to the vibration signal collected by the piezoelectric ceramic sensor, the resonant frequency band range of the vibration signal is judged, and by adjusting the parameters of the two-stage resonator system of the second layer of multifunctional ultra-thin metamaterial, the band gap of the energy band structure of the multifunctional ultra-thin metamaterial covers the resonant frequency band range of the vibration signal, thereby determining the structure of the multifunctional ultra-thin metamaterial.

[0009] Furthermore, it also includes: arranging the multifunctional ultrathin metamaterial with a certain structure as a unit in a periodic array, and the number of arrays is determined according to the size of the actual assembly interface, so as to realize the design of the multifunctional ultrathin metamaterial for the assembly interface.

[0010] Furthermore, the two-stage resonator system includes a metal base frame, and a two-stage resonator system arranged on the metal base frame.

[0011] Furthermore, the base frame is a prism with a U-shaped cross section, and a plurality of square through holes are evenly distributed around the prism.

[0012] Furthermore, the two-stage resonator system includes a primary resonator system and a secondary resonator system, the primary resonator system includes a primary resonator mass block and a primary resonator elastic element, the secondary resonator system includes a secondary resonator mass block and a secondary resonator elastic element; the secondary resonator elastic element is arranged on the metal base frame, the secondary resonator mass block is arranged on the secondary resonator elastic element, the primary resonator elastic element is arranged on the secondary resonator mass block, and the primary resonator mass block is arranged on the primary resonator elastic element.

[0013] Furthermore, the first-stage resonator elastic element is a cylinder with a circular ring cross section, the first-stage resonator mass block is a cylinder, the second-stage resonator elastic element is a cube with a square cross section and a circle removed from the middle, and the second-stage resonator mass block is a cylinder with a circular ring cross section.

[0014] Furthermore, the primary resonator elastic element is arranged in the ring of the secondary resonator mass block, and the primary resonator mass block is arranged in the ring of the primary resonator elastic element.

[0015] Furthermore, the metal matrix frame is made of aluminum alloy material, the first-level resonator elastic element and the second-level resonator elastic element are made of polyurethane material, and the first-level resonator mass block and the second-level resonator mass block are made of lead.

[0016] Furthermore, the Young's modulus, Poisson's ratio and density of aluminum alloy are: 7.76×10 10 Pa, 0.352kg / m 3 and 2730kg / m 3 , the Young's modulus, Poisson's ratio and density of polyurethane materials are: 3×10 5 Pa, 0.49kg / m3 and 1050kg / m 3 .

[0017] Furthermore, the band gap of the energy band structure of the multifunctional ultra-thin metamaterial covers the resonant frequency range of the vibration signal through the following process:

[0018] When the radius R1 of the primary resonator mass block is 0.25 mm and the inner diameter R2 of the secondary resonator mass block is 0.5 mm, the change of the vibration isolation band gap of the metamaterial structure under different values ​​of the outer diameter R3 of the secondary resonator mass block is tested;

[0019] When the outer diameter R3 of the secondary resonator mass block is 4.125mm and the inner diameter R2 of the secondary resonator mass block satisfies R2=R1+0.25mm, the change of the vibration isolation band gap of the metamaterial structure under different values ​​of the radius R1 of the primary resonator mass block is tested; according to the change of the vibration isolation band gap of the metamaterial structure under different values ​​of the outer diameter R3 of the secondary resonator mass block and the change of the vibration isolation band gap of the metamaterial structure under different values ​​of the radius R1 of the primary resonator mass block, the values ​​of the radius of the primary resonator mass block and the inner and outer diameters of the secondary resonator mass block in the two-stage resonator system of the second layer of multifunctional ultra-thin metamaterial are changed, so that the band gap of the multifunctional ultra-thin energy band structure covers the resonant frequency band range of the vibration signal.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] According to the specific physical properties of the ultra-thin metamaterial structure, the present invention builds an ultra-thin metamaterial structure with a two-stage resonant subsystem, proposes a design concept of "multiple vibration modes complementarity", and realizes the special functions of the metamaterial structure by adjusting the parameters of the multi-stage resonant subsystem, and forms a directional design scheme of function-structure-parameter, which provides guidance for the design of the metamaterial vibration isolation and vibration reduction device. The low-frequency ultra-wideband vibration isolation performance of the metamaterial structure with a two-stage resonant subsystem is far superior to that of the traditional metamaterial structure. The present invention sets a multifunctional ultra-thin metamaterial at the assembly connection interface, and sets the parameters of the two-stage resonant subsystem of the unit cell unit in the multifunctional ultra-thin metamaterial to obtain the band structure morphology under different parameters. The band gap of the band structure of the multifunctional ultra-thin metamaterial covers the resonant frequency band range of the vibration signal, thereby realizing the identification of the resonance model of the assembly interface and the ultra-wideband vibration isolation and vibration reduction of the vibration frequency band, which can improve the vibration isolation and vibration reduction performance of the assembly connection structure under complex service conditions, and effectively guarantee the overall performance of high-end equipment such as aircraft engines and motor vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of bolt connection;

[0023] Figure 2 It is a diagram of the structure of the metamaterial with a two-stage resonator system;

[0024] Figure 3 It is a diagram of the band structure of the metamaterial with a two-stage resonator system;

[0025] Figure 4 It is the NMDz diagram corresponding to the band structure of the metamaterial with a two-stage resonator system;

[0026] Figure 5 This is the evolution law diagram of the band gap controlled by the parameters of the second-level resonator system;

[0027] Figure 6 The first-order resonator system parameter control band gap evolution diagram

[0028] Figure 7 It is a structural diagram of a double-layer multifunctional metamaterial vibration isolation / vibration reduction array;

[0029] Figure 8 This is an application diagram of the metamaterial vibration isolation device;

[0030] Among them, 1 is the upper assembly, 2 is the lower assembly, 3 is the bolts and nuts, 4 is the metal matrix frame, 5 is the secondary resonator mass block, 6 is the secondary resonator elastic element, 7 is the primary resonator mass block, 8 is the primary resonator elastic element, 9 is the second layer of multifunctional ultra-thin metamaterial, 10 is the first layer of multifunctional ultra-thin metamaterial, and 11 is the multifunctional ultra-thin metamaterial embedded in the assembly interface. DETAILED DESCRIPTION

[0031] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood.

[0032] See also Figure 8 The multifunctional ultra-thin metamaterial design method for assembly interface of the present invention comprises the following steps:

[0033] (1) Establishing the unit cell structure of multifunctional ultra-thin metamaterials with a two-stage resonator system, such as Figure 2As shown, the structure includes a metal matrix frame 4, and a two-stage resonator system arranged on the metal matrix frame 4. The metal matrix frame 4 has a prism with a cross section of "U" shape, and 5 square through holes with a length of 1.5 mm and a width of 0.5 mm are evenly distributed around the prism. The two-stage resonator system includes a primary resonator system and a secondary resonator system. Each resonator system includes an elastic element and a mass block. Specifically, the primary resonator system includes a primary resonator mass block 7 and a primary resonator elastic element 8, and the secondary resonator system includes a secondary resonator mass block 5 and a secondary resonator elastic element 6. The primary resonator elastic element 8 is a cylinder with a circular ring cross section, and the primary resonator mass block 7 is a cylinder. The secondary resonator elastic element 6 is a cube with a square cross section and a circle removed from the middle, and the secondary resonator mass block 5 is a cylinder with a circular ring cross section. The secondary resonator elastic element 6 is arranged on the metal base frame 4, the secondary resonator mass block 5 is arranged on the secondary resonator elastic element 6, the primary resonator elastic element 8 is arranged in the ring of the secondary resonator mass block 5, and the primary resonator mass block 7 is arranged in the ring of the primary resonator elastic element 8.

[0034] The metal base frame 4 is made of aluminum alloy, and its Young's modulus, Poisson's ratio and density are: 7.76×10 10 Pa, 0.352kg / m 3 and 2730kg / m 3 The first-stage resonator elastic element 8 and the second-stage resonator elastic element 6 are made of polyurethane material, and their Young's modulus, Poisson's ratio and density are respectively: 3×10 5 Pa, 0.49kg / m 3 and 1050kg / m 3 The primary resonator mass block 7 and the secondary resonator mass block 5 use lead as the material, and their Young's modulus, Poisson's ratio and density are: 4.08×10 10 Pa, 0.369kg / m 3 and 11600kg / m 3 .

[0035] (2) The multifunctional ultra-thin metamaterial is arranged on the assembly interface. The multifunctional ultra-thin metamaterial includes two layers in total. A piezoelectric ceramic sensor is attached to the surface of the first layer of the multifunctional ultra-thin metamaterial 10 to monitor the vibration signal of the high-end equipment assembly interface during service in real time. At the same time, the piezoelectric ceramic sensor can output the vibration signal in real time, and its measurement error is between ±1%. The vibration signal can be displayed in real time on the display.

[0036] The length, width and height of the first and second layers of multifunctional ultra-thin metamaterials are 10mm, 10mm and 1mm respectively. Each layer of multifunctional ultra-thin metamaterials includes three materials: polyurethane, lead and aluminum alloy.

[0037] (3) According to the vibration signal collected by the piezoelectric ceramic sensor, the resonant frequency band range of the vibration signal is determined, and by changing the values ​​of the radius of the first-stage resonator mass block and the inner and outer diameters of the second-stage resonator mass block in the two-stage resonator system of the second-layer multifunctional ultra-thin metamaterial 9, the band gap of the multifunctional ultra-thin band structure covers the resonant frequency band of the vibration signal, thereby realizing the design of the structure of the multifunctional ultra-thin metamaterial for the assembly interface and realizing ultra-wide frequency range vibration isolation for the assembly connection interface of high-end equipment.

[0038] Among them, by changing the values ​​of the radius of the first-stage resonator mass block and the inner and outer diameters of the second-stage resonator mass block in the two-stage resonator system of the second-layer multifunctional ultra-thin metamaterial 9, the band gap of the multifunctional ultra-thin energy band structure covers the resonant frequency band of the vibration signal, thereby realizing the design of the structure of the multifunctional ultra-thin metamaterial for the assembly interface, including the following steps:

[0039] When the radius R1 of the primary resonator mass block is 0.25 mm and the inner diameter R2 of the secondary resonator mass block is 0.5 mm, the vibration isolation band gap change of the metamaterial structure is tested under different values ​​of the outer diameter R3 of the secondary resonator mass block. For the vibration isolation band gap change, see Figure 5 .

[0040] When the outer diameter R3 of the secondary resonator mass block is 4.125 mm and the inner diameter R2 of the secondary resonator mass block is: R2 = R1 + 0.25 mm, the vibration isolation band gap change of the metamaterial structure under different values ​​of the radius R1 of the primary resonator mass block is tested. For the vibration isolation band gap change, refer to Figure 6 .

[0041] according to Figure 5 and Figure 6 By changing the radius of the first-stage resonator mass block and the inner and outer diameters of the second-stage resonator mass block in the two-stage resonator system of the second-layer multifunctional ultra-thin metamaterial, it is ensured that the band gap of the multifunctional ultra-thin band structure covers the resonant frequency band of the vibration signal, thereby determining the structure of the multifunctional ultra-thin metamaterial used for the assembly interface and achieving ultra-wide frequency range vibration isolation for the assembly connection interface of high-end equipment.

[0042] (4) The multifunctional ultrathin metamaterial with the structure determined in step (3) is arranged as a unit in a periodic array, and the number of arrays is determined according to the size of the actual assembly interface, thereby realizing the design of the multifunctional ultrathin metamaterial for the assembly interface.

[0043] See also Figure 7 , Figure 7 A periodic array of 5 units in two directions on the horizontal plane is shown in FIG.

[0044] The present invention is further described below in conjunction with specific embodiments.

[0045] See also Figure 1 , taking the most common bolt connection structure as the application object, the bolt connection structure includes an upper assembly 1 and a lower assembly 2, the upper assembly 1 and the lower assembly 2 are connected by bolts and nuts 3, and the multifunctional ultra-thin metamaterial 11 embedded in the assembly interface is used as the intermediate layer of the bolt connection interface, such as Figure 8 shown.

[0046] (1) Establish multifunctional ultra-thin metamaterial structures with dual-stage resonator systems, such as Figure 2 As shown, the structure includes a metal matrix frame 4, wherein each two-stage resonant subsystem includes a primary resonant subsystem and a secondary resonant subsystem. Each resonant subsystem includes an elastic element and a mass block. The metal matrix frame 4 is made of aluminum alloy material, the elastic element is made of polyurethane material, and the mass block is made of lead.

[0047] The periodic symmetry condition is set for the multifunctional ultra-thin metamaterial structure with a two-stage resonator system, and the frequency is swept in the first Brillouin zone to obtain the band structure diagram of the structure as shown in the figure below: Figure 3 As shown, it can be seen that the band gap of the band structure is easily opened. By extracting the average out-of-plane displacement of the metamaterial structure at different frequencies, the NMDz diagram of the structure is obtained, see Figure 4 , an out-of-plane wave low-frequency ultra-wide band gap of 104-364 Hz can be obtained, which indicates that the energy transmission performance of the structure in the range of 104-364 Hz is extremely low, and it plays a vibration isolation / vibration reduction effect.

[0048] (2) The parameters of the two-stage resonator system of the metamaterial structure are adjusted to extract the band gap range of the band structure and obtain the band gap diagram of the two-stage resonator system under different parameters, such as Figure 5 and Figure 6 As shown in the figure, it can be seen that by adjusting different parameters, the band gap exhibits switching characteristics and can be used as a logic gate to realize the opening and closing of the mechanical structure band gap. The radius R1 of the first-stage resonator mass block is designed to be 0.25mm, the inner diameter R2 of the second-stage resonator mass block is 0.5mm, and the outer diameter R3 is 3.5mm. Figure 7 Finally, the double-layer ultra-thin metamaterial array structure is placed in the middle layer of the assembly interface and fixed uniformly with bolts, as shown in FIG. Figure 8 shown.

[0049] The present invention utilizes the switching characteristics of multifunctional metamaterials to adjust the parameters of the second-stage resonator system corresponding to different switching frequencies, and then identifies the resonance frequency through the output signal of the piezoelectric ceramic sensor of the resonator of the metamaterial device, and then clearly defines the vibration isolation frequency band of the mating surface; according to the vibration isolation frequency band of the assembly interface, coordinately adjust the parameters of the two-stage resonator system to form an ultra-wide vibration isolation band gap and a switching band gap within a specific low-frequency range. The present invention can achieve the resonance frequency identification and ultra-wideband vibration isolation of the assembly connection interface by adjusting the specific parameters of the metamaterial with multiple vibration isolation layers at the assembly interface, improve the energy loss capacity of the assembly interface, and effectively ensure the dynamic connection performance of various components of high-end equipment such as rocket engines, high-end machine tools, ships, and submarines.

[0050] The above description is only for the best embodiment of the present invention, but it should not be understood as limiting the claims. The present invention is not limited to the above embodiments, and its specific structure is allowed to be changed. However, all changes made within the protection scope of the independent claims of the present invention are within the protection scope of the present invention.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

Claims

1. A multifunctional ultra-thin metamaterial design method for assembly interface, characterized in that: The following steps are involved: The multifunctional ultra-thin metamaterial is arranged on the assembly interface, wherein the multifunctional ultra-thin metamaterial comprises two connected layers, and a piezoelectric ceramic sensor is attached to the surface of the first layer of the multifunctional ultra-thin metamaterial; wherein the multifunctional ultra-thin metamaterial has a two-stage resonator system; According to the vibration signal collected by the piezoelectric ceramic sensor, the resonant frequency band range of the vibration signal is judged, and by adjusting the parameters of the two-stage resonator system of the second layer of multifunctional ultra-thin metamaterial, the band gap of the energy band structure of the multifunctional ultra-thin metamaterial covers the resonant frequency band range of the vibration signal, thereby determining the structure of the multifunctional ultra-thin metamaterial.

2. The multifunctional ultra-thin metamaterial design method for assembly interface according to claim 1, characterized in that: Also includes: The multifunctional ultrathin metamaterial with a certain structure is taken as a unit and arranged in a periodic array. The number of arrays is determined according to the size of the actual assembly interface, thereby realizing the design of the multifunctional ultrathin metamaterial for the assembly interface.

3. The multifunctional ultra-thin metamaterial design method for assembly interface according to claim 1, characterized in that: The double-stage resonator system comprises a metal base frame (4) and a double-stage resonator system arranged on the metal base frame (4).

4. The multifunctional ultra-thin metamaterial design method for assembly interface according to claim 3, characterized in that: The base frame (4) is a prism with a cross section in the shape of a Chinese character U, and a plurality of square through holes are evenly distributed around the prism.

5. The multifunctional ultra-thin metamaterial design method for assembly interface according to claim 1, characterized in that: The two-stage resonator system comprises a primary resonator system and a secondary resonator system; the primary resonator system comprises a primary resonator mass block (7) and a primary resonator elastic element (8); the secondary resonator system comprises a secondary resonator mass block (5) and a secondary resonator elastic element (6); the secondary resonator elastic element (6) is arranged on a metal base frame (4), the secondary resonator mass block (5) is arranged on the secondary resonator elastic element (6), the primary resonator elastic element (8) is arranged on the secondary resonator mass block (5), and the primary resonator mass block (7) is arranged on the primary resonator elastic element (8).

6. The multifunctional ultra-thin metamaterial design method for assembly interface according to claim 5, characterized in that: The first-stage resonator elastic element (8) is a cylinder with a circular ring cross section, the first-stage resonator mass block (7) is a cylinder, the second-stage resonator elastic element (6) is a cube with a square cross section and a circle removed from the middle, and the second-stage resonator mass block (5) is a cylinder with a circular ring cross section.

7. The multifunctional ultra-thin metamaterial design method for assembly interface according to claim 6, characterized in that: The primary resonator elastic element (8) is arranged in the circular ring of the secondary resonator mass block (5), and the primary resonator mass block (7) is arranged in the circular ring of the primary resonator elastic element (8).

8. The multifunctional ultra-thin metamaterial design method for assembly interface according to claim 1, characterized in that: The metal base frame (4) is made of aluminum alloy material, the first-level resonator elastic element (8) and the second-level resonator elastic element (6) are made of polyurethane material, and the first-level resonator mass block (7) and the second-level resonator mass block (5) are made of lead.

9. The multifunctional ultra-thin metamaterial design method for assembly interface according to claim 8, characterized in that: The Young's modulus, Poisson's ratio and density of aluminum alloy are: 7.76×10 10 Pa, 0.352kg / m 3 and 2730kg / m 3 , the Young's modulus, Poisson's ratio and density of polyurethane materials are: 3×10 5 Pa, 0.49kg / m 3 and 1050kg / m 3 .

10. The multifunctional ultra-thin metamaterial design method for assembly interface according to claim 1, characterized in that: The band gap of the energy band structure of the multifunctional ultra-thin metamaterial covers the resonant frequency range of the vibration signal through the following process: When the radius R1 of the primary resonator mass block is 0.25 mm and the inner diameter R2 of the secondary resonator mass block is 0.5 mm, the change of the vibration isolation band gap of the metamaterial structure under different values ​​of the outer diameter R3 of the secondary resonator mass block is tested; When the outer diameter R3 of the secondary resonator mass block is 4.125 mm and the inner diameter R2 of the secondary resonator mass block satisfies R2=R1+0.25 mm, the vibration isolation band gap change of the metamaterial structure under different values ​​of the radius R1 of the primary resonator mass block is tested; According to the change of the vibration isolation band gap of the metamaterial structure at different values ​​of the outer diameter R3 of the secondary resonator mass block and the change of the vibration isolation band gap of the metamaterial structure at different values ​​of the radius R1 of the primary resonator mass block, the values ​​of the radius of the primary resonator mass block and the inner and outer diameters of the secondary resonator mass block in the two-stage resonator system of the second layer of multifunctional ultra-thin metamaterial are changed, so that the band gap of the multifunctional ultra-thin band structure covers the resonant frequency band range of the vibration signal.

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