Liquid resistance vibration reduction device with multi-stage segmented acoustic black hole structure

Abstract

The present invention discloses a liquid-resistance vibration reduction device with a multi-stage segmented acoustic black hole structure, comprising a cylinder cup filled with damping fluid and a multi-stage segmented acoustic black hole structure disposed within the cylinder cup; the multi-stage segmented acoustic black hole structure comprises a plurality of acoustic black hole structures stacked in parallel with each other, each having a segmented power-finger profile; an inertial channel damping disk is disposed between two adjacent acoustic black hole structures; the multi-stage segmented acoustic black hole structure includes but is not limited to a first-stage acoustic black hole structure and a second-stage acoustic black hole structure; the inertial channel damping disk is provided with a plurality of inertial channels for passage of the damping fluid; a connecting rod of the first-stage acoustic black hole structure extends from the cylinder cup and connects to a top disk. Compared with the prior art, the present invention has the advantages of a low cutoff frequency, a wide effective bandwidth, and robust and controllable damping characteristics. The present invention utilizes a multi-stage segmented acoustic black hole structure, which can filter, grade, and focus bending waves propagating in the structure, achieving a vibration reduction effect with a lower cutoff frequency and a wider bandwidth.

Description

Technical Field

[0001] The present invention belongs to the technical field of structural vibration and noise reduction, and in particular relates to a broadband adsorbable active liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure. Background Art

[0002] With the widespread application of lightweight structural design in aerospace, high-speed rail transit, electric vehicles, large oil / electric driven engineering machinery and other fields, the lightweight and high strength of structures have been greatly improved, but the problems of structural vibration and structural sound radiation have become increasingly prominent.

[0003] The main mechanism for structural vibration and sound radiation is that the bending wave in the structure is reflected after encountering boundary conditions such as truncation or structural defects during propagation, forming a standing wave with the original bending wave, generating structural vibration, and the elastic wave is coupled with the ambient sound medium, and the evanescent wave escapes to generate structural sound radiation.

[0004] Therefore, controlling the bending waves in the structure through master control design and sticking damping materials on the surface of the structure are currently common methods to deal with structural vibration and sound radiation.

[0005] However, the adhesion of the damping layer usually introduces external mass into the system, and the effectiveness of the damping layer cannot be guaranteed in the face of various working environments. The cutoff frequency of structural vibration suppression needs to be further improved.

[0006] In addition, the current active control costs on the market are high and the mechanism design is relatively complex, which is not conducive to widespread promotion and application.

[0007] An acoustic black hole structure is one in which the cross-sectional thickness is manufactured or tailored according to a power-law function. Such structures exploit variations in local geometric parameters to achieve a gradient in material properties, thereby creating an acoustic black hole effect. This effect is achieved by gradually changing the impedance of the structure, causing the propagation velocity of flexural waves in the acoustic black hole region to gradually decrease, ideally achieving zero reflection.

[0008] Therefore, the acoustic black hole structure can control and trap the bending waves in the structure, and can effectively suppress structural vibration and sound radiation.

[0009] However, most existing acoustic black hole structures, on the one hand, only follow a single power law in a section of a one-dimensional or two-dimensional acoustic black hole unit, and then form an acoustic black hole structure system through repeated stacking and arrangement in space. This design can achieve a certain degree of vibration reduction effect in the corresponding frequency band, but the effective frequency band is relatively single;

[0010] On the other hand, the acoustic black hole structure commonly manufactured is difficult to achieve an ideal state. By gluing, the damping layer can further improve its acoustic black hole effect, but the gluing parameters of the damping layer are difficult to accurately control, and the gluing effect is difficult to guarantee in a variety of working environments.

[0011] Therefore, there is an urgent need in this field to design a new vibration reduction device with an acoustic black hole structure that has filtering characteristics, low cutoff frequency, wide bandwidth, and robust and controllable damping characteristics, so as to achieve effective structural vibration reduction and sound radiation suppression of the system structure under complex and extreme working conditions such as high speed, high temperature, heavy load, large impact, and multiple excitation fields. Summary of the Invention

[0012] The object of the present invention is to provide a liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure that can solve the above problems and achieve effective structural vibration reduction and sound radiation suppression for the system structure.

[0013] The present invention discloses a liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure, comprising a cylinder cup filled with damping liquid and a multi-stage segmented acoustic black hole structure arranged in the cylinder cup;

[0014] The multi-stage segmented acoustic black hole structure comprises a plurality of acoustic black hole structures stacked in parallel and having segmented power-finger profiles; an inertial channel damping disk is provided between two adjacent acoustic black hole structures;

[0015] The multi-stage segmented acoustic black hole structure includes but is not limited to a first-stage acoustic black hole structure and a second-stage acoustic black hole structure;

[0016] The inertia channel damping disk is provided with a plurality of inertia channels for the damping fluid to pass through;

[0017] The connecting rod of the first-stage acoustic black hole structure extends out of the cylinder cup and is connected to the top plate.

[0018] Furthermore, the acoustic black hole structure is formed by a circumferential array of segmented acoustic black hole beam structure units; the segmented acoustic black hole beam structure units have multiple sections of variable thickness, and the number of sections is at least segments.

[0019] Furthermore, the segmented acoustic black hole beam structure unit includes a uniform beam region and a segmented acoustic black hole region sequentially arranged from the inside to the outside along the radial direction;

[0020] The uniform beam area has a constant beam thickness; the segmented acoustic black hole area structure includes multiple variable cross-section areas, and the beam thickness of each variable cross-section area varies in a power function; in the vertical direction, the segmented acoustic black hole area is located within the inertial channel area of the inertial channel damping disk.

[0021] Furthermore, the segmented acoustic black hole region includes a first segment acoustic black hole region, a second segment acoustic black hole region and a third segment acoustic black hole region;

[0022]

[0023] Where x represents the horizontal distance from a point in the variable cross-section region of the segmented acoustic black hole beam to the edge of the acoustic black hole structure, h(x) represents the thickness of the section at that point, m1, m2, and m3 represent the power exponents obeyed by the first, second, and third segments of the segmented acoustic black hole, respectively, and m1, m2, and m3 must be greater than or equal to 2. ε1, ε2, and ε3 represent the variable cross-section coefficients of each segment of the power function, respectively.

[0024] Furthermore, the top plate includes a metal plate that contacts the vibration-damping component and a strong magnetic annular component arranged in the metal plate.

[0025] Furthermore, the damping fluid is viscous silicone oil.

[0026] Furthermore, the cylinder cup is provided with an oil filling hole and an oil extraction hole; the oil filling hole and the oil extraction hole are used to connect to the fluid resistance control system to realize the addition and replacement of the damping fluid in the cylinder cup;

[0027] The hydraulic resistance control system includes a waste oil recovery tank connected to the oil extraction hole for recovering waste oil from the cylinder cup and a silicone oil tank connected to the oil injection hole for providing damping liquid to the cylinder cup;

[0028] The silicone oil box includes a high-viscosity silicone oil adding box, a medium-viscosity silicone oil adding box, and a low-viscosity silicone oil adding box.

[0029] Furthermore, the liquid outlet of the silicone oil tank is provided with an electromagnetic switch valve; the electromagnetic switch valve includes a first electromagnetic switch valve, a second electromagnetic switch valve and a third electromagnetic switch valve;

[0030] The first electromagnetic switch valve controls the liquid outflow of the high-viscosity silicone oil addition box, the second electromagnetic switch valve controls the liquid outflow of the medium-viscosity silicone oil addition box, and the third electromagnetic switch valve controls the liquid outflow of the low-viscosity silicone oil addition box;

[0031] Under the action of the motor, the oil pump sends the damping liquid in the silicone oil tank into the oil filling hole through the oil filling pipe;

[0032] The motor, the electromagnetic switch valve, and the acceleration sensor provided on the metal plate are electrically connected to a lower computer control board. The acceleration sensor measures the vibration signal on the vibration-damped component and transmits it to the lower computer control board. The control board outputs high and low levels according to the signal characteristics to control the operation of the motor and the opening and closing of the corresponding electromagnetic switch valve.

[0033] One end of the oil extraction pipeline is connected to the oil extraction hole, and the other end is connected to the waste oil recovery tank to collect the replaced and discharged waste oil.

[0034] The beneficial effects of the present invention are:

[0035] 1. Compared with existing technologies, this invention offers the advantages of a low cutoff frequency, a wide effective bandwidth, and robust and controllable damping characteristics. It employs a multi-stage segmented acoustic black hole structure, which filters and aggregates flexural waves propagating through the structure. The combined effects of these various levels of flexural wave aggregation achieve vibration reduction with a lower cutoff frequency and a wider bandwidth.

[0036] 2. The present invention uses high-viscosity silicone oil liquid resistance and an inertial channel damping disc structure. The liquid damping material can more fully contact the acoustic black hole structure and has the advantages of stable performance, heat resistance and cold resistance. When combined with the inertial channel damping disc structure, it can further improve the liquid damping energy dissipation effect, so that the device can obtain a more stable acoustic black hole effect and vibration reduction effect.

[0037] 3. The present invention adopts an active liquid resistance device, which can actively control the liquid damping in the device. According to the working conditions with different vibration characteristics, the viscosity of the liquid resistance in the device is actively adjusted to achieve more effective damping characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 Schematic diagram of the overall structure of the hydraulic resistance vibration reduction device of the present invention;

[0039] Figure 2 Schematic cross-section of the cylinder cup of the present invention;

[0040] Figure 3 for Figure 2 Schematic diagram of the decomposition;

[0041] Figure 4 Schematic diagram of the segmented acoustic black hole structure in the present invention;

[0042] Figure 5 Schematic diagram of the three-level acoustic black hole structure in the present invention;

[0043] Figure 6 Schematic diagram and cross-sectional view of the structure of the inertial channel damping disk of the present invention;

[0044] Figure 7 Schematic diagram of the fixed installation position of the single-stage acoustic black hole structure and the inertial channel damping disk in the present invention;

[0045] Figure 8 This is a control principle diagram of the hydraulic resistance control system in the present invention. DETAILED DESCRIPTION

[0046] The present invention will be described in detail below with reference to the accompanying drawings:

[0047] This invention proposes a broadband, adsorbable, active hydraulic damping device with a multi-stage, segmented acoustic black hole structure. Through the multi-stage, multi-segment acoustic black hole design and the active control of the hydraulic resistance, the device boasts a low cutoff frequency, a wide effective bandwidth, and robust and controllable damping characteristics. This device is primarily applicable to damped structures such as construction machinery cab floors, high-speed rail panels, tracks, and engine support structures, achieving ideal vibration and noise reduction.

[0048] In order to more clearly and easily demonstrate the above-mentioned objects and advantages of the present invention, further description will be given below in conjunction with specific implementations and accompanying drawings.

[0049] Figure 1 This is a structural schematic diagram of an embodiment of a broadband adsorbable active liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure of the present invention. The device includes a multi-stage segmented acoustic black hole vibration reduction system and a liquid resistance control system. The multi-stage segmented acoustic black hole vibration reduction system is a liquid resistance vibration reduction device, and the liquid resistance control system is a multi-viscosity silicone oil replacement device.

[0050] See also Figure 1-3 The structure of the multi-stage segmented acoustic black hole liquid resistance vibration reduction device includes: a metal plate 2 and multiple strong magnetic annular components 3 fixedly connected to form an adsorbable top plate, a first-stage acoustic black hole structure 4, a second-stage acoustic black hole structure 6, a third-stage acoustic black hole structure 8, a first inertia channel damping plate 5 and a second inertia channel damping plate 7, a liquid resistance 11, and a cylinder cup assembled by a cylinder cup cover 9 and a cylinder cup body 10.

[0051] The metal plate 2 and the plurality of annular strong magnetic components 3 are fixedly connected to form an adsorbable top plate, which is used to ensure the convenience of disassembly and assembly and to ensure that the rigidity of the vibration-damped structure is not damaged.

[0052] The cylinder cup cover 9 is put on the first-stage acoustic black hole structure 4 and fixed, and the fixed part is fixed on the adsorbable top plate.

[0053] Subsequently, the first inertial channel damping disk 5, the second-stage acoustic black hole structure 6, the inertial channel damping disk 7, and the third-stage acoustic black hole structure 8 are fixed in sequence along the central axis, and the fixed whole is fixed to the first-stage acoustic black hole 4 along the central axis, and the cylinder cup body 10 is sealed and connected to the cylinder cup cover.

[0054] The liquid damping inside the cylinder cup uses silicone oil polydimethylsiloxane (PDMS), which is injected into the cylinder cup through a pipe. The oil injection pipe 16 and the oil extraction pipe 14 are connected to the oil injection hole 12 at the bottom of the cylinder cup body and the oil extraction hole 13 at the top of the cylinder cup cover, respectively. The external upper and lower pressure differential controls the replacement of the silicone oil in the cylinder cup.

[0055] like Figure 4 As shown, Figure 4(b) is the basic acoustic black hole beam structure unit of each level of segmented acoustic black hole structure. Figure 4 (a) is a schematic diagram of the cross-sectional thickness of the basic acoustic black hole beam structure unit. Taking the side of the beam close to the cylinder cup as the origin, the cross-sectional thickness of the beam changes as a piecewise power function. The expression of its thickness variation is:

[0056]

[0057] Where x represents the horizontal distance from a point in the variable cross-section region of the segmented acoustic black hole beam to the edge of the acoustic black hole structure, h(x) represents the thickness of the section at that point, m1, m2, and m3 represent the power exponents obeyed by the first, second, and third segments of the segmented acoustic black hole, respectively, and m1, m2, and m3 must be greater than or equal to 2. ε1, ε2, and ε3 represent the variable cross-section coefficients of each segment of the power function, respectively.

[0058] like Figure 5 As shown, use Figure 4 The a, b, and c basic segmented acoustic black hole beam structure units are rotated around the central axis to form the first, second, and third level segmented acoustic black hole structures. Each level of the segmented acoustic black hole structure is made of the same material as the structure to be vibrated, ensuring impedance matching between the vibration reduction device and the structure to be vibrated, so that the bending waves in the structure to be vibrated can smoothly enter the vibration reduction device.

[0059] like Figure 6 As shown, the inertial channel damping disk in this embodiment is designed with a certain density of inertial channels, and the diameter of the through-holes can be determined according to actual operating conditions. The inertial channel damping disk is also made of the same material as the structure being damped to ensure impedance matching with the segmented acoustic black hole structure connected above and below, and to ensure the propagation of bending waves.

[0060] like Figure 7 As shown, the inertial channel damping disk must be installed as close as possible to the acoustic black hole area of the segmented acoustic black hole structure, and the inertial channel density on the inertial channel damping disk must be large enough so that the inertial channel area can cover the adjacent acoustic black hole area.

[0061] Figure 8 This is a schematic diagram of the hydraulic resistance control principle of an embodiment of the present invention. Acceleration sensor 26, located on the damped component 1, detects the component's vibration acceleration time-domain signal and transmits it to the lower-level control board. The main control chip performs a fast Fourier transform on the acceleration time-domain signal to obtain the vibration acceleration frequency-domain signal. All vibration acceleration peaks within the frequency band of interest are selected and their arithmetic mean is calculated. The lower-level control board's main control chip can be an STM32F103ZET6.

[0062] When the arithmetic mean of the vibration acceleration peak value is greater than 0.3g, the main control chip outputs high and low levels, controls the motor 18 to start, and makes the oil pump 17 work. At the same time, it controls the first electromagnetic switch valve 19 corresponding to the high-viscosity silicone oil circuit where the 5000cst high-viscosity silicone oil adding box 23 is located to open, so that the high-viscosity silicone oil circuit is unblocked. At this time, the oil in the high-viscosity silicone oil circuit can smoothly enter the cylinder cup cavity of the multi-stage segmented acoustic black hole structure liquid resistance vibration reduction device.

[0063] When the arithmetic mean of the vibration acceleration peak value is within the range of 0.15g-0.3g, the main control chip outputs high and low levels, controls the motor 18 to start, and makes the oil pump 17 work. At the same time, it controls the second electromagnetic switch valve 20 corresponding to the medium-viscosity silicone oil circuit where the 3000cst medium-viscosity silicone oil addition box 24 is located to open, so that the medium-viscosity silicone oil circuit is unblocked. At this time, the oil in the medium-viscosity silicone oil circuit can smoothly enter the cylinder cup cavity of the multi-stage segmented acoustic black hole structure liquid resistance vibration reduction device.

[0064] When the arithmetic mean of the vibration acceleration peak is below 0.15g, the main control chip outputs high and low levels, controls the motor to start, and makes the oil pump work. At the same time, it controls the third electromagnetic switch valve 21 corresponding to the low-viscosity silicone oil circuit where the 2000cst low-viscosity silicone oil adding box 25 is located to open, so that the low-viscosity silicone oil circuit is unobstructed. At this time, the oil in the low-viscosity silicone oil circuit can smoothly enter the cylinder cup cavity of the multi-stage segmented acoustic black hole structure liquid resistance vibration reduction device.

[0065] The lower computer control board can also send information such as the vibration acceleration spectrum, vibration acceleration peak, arithmetic mean of vibration acceleration peak, motor control level status, and electromagnetic switch valve level control status to the upper computer for real-time data monitoring. The upper computer can also transmit control signals to the lower computer to control the opening and closing status of the motor 18 and the electromagnetic switch valve.

[0066] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit them. Those skilled in the art will appreciate that the technical solutions described in the aforementioned embodiments may be modified, or some of the technical features thereof may be replaced with equivalents; such modifications or replacements do not deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure, characterized by: It comprises a cylinder cup filled with damping fluid (11) and a multi-stage segmented acoustic black hole structure arranged in the cylinder cup; The multi-stage segmented acoustic black hole structure comprises a plurality of acoustic black hole structures stacked in parallel and having segmented power-finger profiles; an inertial channel damping disk is provided between two adjacent acoustic black hole structures; The multi-stage segmented acoustic black hole structure includes but is not limited to a first-stage acoustic black hole structure (4) and a second-stage acoustic black hole structure (6); The inertia channel damping disk is provided with a plurality of inertia channels through which the damping fluid (11) can pass; The connecting rod of the first-stage acoustic black hole structure (4) extends out of the cylinder cup and is connected to the top plate.

2. The liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure according to claim 1 is characterized in that: The acoustic black hole structure is formed by a circumferential array of segmented acoustic black hole beam structure units; the segmented acoustic black hole beam structure units have multiple sections with variable thickness, and the number of sections is at least 2.

3. The liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure according to claim 2, characterized in that: The segmented acoustic black hole beam structure unit includes a uniform beam region and a segmented acoustic black hole region sequentially arranged from the inside to the outside along the radial direction; The uniform beam region has a constant beam thickness; the segmented acoustic black hole region includes multiple variable cross-section regions, and the beam thickness of each variable cross-section region varies in a power function; in the vertical direction, the segmented acoustic black hole region is within the inertial channel region of the inertial channel damping disk.

4. The liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure according to claim 3 is characterized in that: The segmented acoustic black hole region includes a first segment acoustic black hole region, a second segment acoustic black hole region and a third segment acoustic black hole region; The thickness of the multi-section variable thickness section changes according to a piecewise power function, and the piecewise power function is: Where x represents the horizontal distance from a point in the variable cross-section region of the segmented acoustic black hole beam to the edge of the acoustic black hole structure, h(x) represents the thickness of the section at that point, m1, m2, and m3 represent the power exponents obeyed by the first, second, and third segments of the segmented acoustic black hole, respectively, and m1, m2, and m3 must be greater than or equal to 2. ε1, ε2, and ε3 represent the variable cross-section coefficients of each segment of the power function, respectively.

5. The liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure according to claim 1, characterized in that: The top plate comprises a metal plate (2) contacting a vibration-damping component (1) and a strong magnetic annular component (3) arranged in the metal plate (2).

6. The liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure according to claim 1, characterized in that: The damping liquid (11) is made of viscous silicone oil.

7. The liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure according to claim 5, characterized in that: The cylinder cup is provided with an oil filling hole (12) and an oil extraction hole (13); the oil filling hole (12) and the oil extraction hole (13) are used to connect to a fluid resistance control system to enable addition and replacement of the damping fluid in the cylinder cup; The hydraulic resistance control system comprises a waste oil recovery tank (15) connected to the oil extraction hole (13) for recovering waste oil in the cylinder cup, and a silicone oil tank (22) connected to the oil injection hole (12) for providing damping liquid to the cylinder cup; The silicone oil box (22) comprises a high-viscosity silicone oil adding box (23), a medium-viscosity silicone oil adding box (24), and a low-viscosity silicone oil adding box (25).

8. The liquid resistance vibration reduction device with a multi-stage segmented acoustic black hole structure according to claim 7, characterized in that: The liquid outlet of the silicone oil tank (22) is provided with an electromagnetic switch valve; the electromagnetic switch valve comprises a first electromagnetic switch valve (19), a second electromagnetic switch valve (20) and a third electromagnetic switch valve (21); The first electromagnetic switch valve (19) controls the discharge of the high-viscosity silicone oil addition box (23), the second electromagnetic switch valve (20) controls the discharge of the medium-viscosity silicone oil addition box (24), and the third electromagnetic switch valve (21) controls the discharge of the low-viscosity silicone oil addition box (25); The oil pump (17) is driven by the motor (18) to deliver the damping liquid in the silicone oil tank (22) into the oil filling hole (12) through the oil filling pipe (16); The motor (18), the electromagnetic switch valve, and the acceleration sensor (26) provided on the metal plate (2) are electrically connected to a lower computer control board. The acceleration sensor (26) measures a vibration signal on the vibration-damped component and transmits it to the lower computer control board. The control board outputs a high or low level according to the signal characteristics, controls the operation of the motor (18), and simultaneously controls the opening and closing of the corresponding electromagnetic switch valve. One end of the oil extraction pipeline (14) is connected to the oil extraction hole (13), and the other end is connected to the waste oil recovery tank (15) to collect the replaced and discharged waste oil.

Images