Tuning type tubular acoustic black hole hydraulic pulsation attenuation-energy harvesting composite system

Abstract

The invention discloses a tuning type tubular acoustic black hole hydraulic pulsation attenuation-energy harvesting composite system which comprises a shell, a micro-lattice acoustic metamaterial, an acoustic black hole partition plate, a piezoelectric corrugated diaphragm, a Helmholtz resonance unit and a cavity adjusting mechanism. Medium-high frequency pulsation (500Hz-2000Hz) in the hydraulic oil is attenuated through the gradient porosity micro-lattice acoustic metamaterial, and low frequency pulsation is focused through the acoustic black hole partition plate and then drives the piezoelectric corrugated diaphragm to deform and generate electricity. The four-channel reducing neck pipe around the diaphragm and the containing cavity form a Helmholtz resonator for balancing static pressure, and the volume of the containing cavity is adjusted through the air cylinder to adapt to residual frequency pulsation. According to the invention, integration of multi-band suppression and energy recovery of hydraulic pulsation is realized.

Description

Technical Field

[0001] This invention relates to the field of hydraulic system pressure control and piezoelectric energy recovery technology, specifically a hydraulic pulsation suppression-energy harvesting composite system that combines microlattice acoustic metamaterial attenuation, acoustic black hole focusing, Helmholtz resonance and cavity adjustment. Background Technology

[0002] Hydraulic system pressure pulsation suppression often employs devices such as throttle valves and accumulators, but these suffer from high energy consumption and poor suppression effects at mid-to-high frequencies. While microlattice acoustic metamaterials can attenuate pulsations in specific frequency bands, they lack multi-band adaptability; acoustic black hole structures can be used for wave energy focusing, but they are not integrated with energy recovery. Existing piezoelectric energy harvesting devices struggle to operate efficiently in hydraulic pulsation environments and lack a hydrostatic balancing mechanism. Therefore, a composite system capable of synergistically suppressing multi-frequency pulsations and recovering energy is needed. Summary of the Invention

[0003] This invention achieves synergy between multi-band pulsation suppression and energy recovery by using microlattice acoustic metamaterials to attenuate high-frequency pulsations, acoustic black hole septa to focus low-frequency pulsations to enhance piezoelectric diaphragm deformation, Helmholtz resonators to balance static pressure, and cylinders to adjust the cavity volume to eliminate residual frequency pulsations. Through multi-structure synergy, it solves the problem that a single technology cannot cover multi-frequency pulsations.

[0004] Furthermore, the tuned tubular acoustic black hole hydraulic pulsation attenuation-energy capture composite system includes a top cover, plunger, shell, piezoelectric ceramic sheet, piezoelectric corrugated diaphragm, acoustic black hole partition, microlattice acoustic metamaterial, titanium alloy support frame, tee pipe joint, etc.

[0005] Furthermore, in the above-mentioned hydraulic pulsation attenuation-energy-harvesting composite system based on harmonic tubular acoustic black hole, the inner surface of the titanium alloy support frame is provided with multiple positioning grooves for embedding 12 acoustic black hole partitions, the first resonant cavity and the second resonant cavity; and the positioning grooves of adjacent two used to place acoustic black hole partitions adopt a hollow structure design.

[0006] Furthermore, in the above-mentioned resonant tubular acoustic black hole hydraulic pulsation attenuation-energy capture composite system, the upper end face of the first resonant cavity is provided with an installation groove for positioning and installing the lower cover plate; the lead wire of the piezoelectric ceramic sheet passes through the circular wire hole on the side wall of the first resonant cavity, the internal channel of the second resonant cavity, and the cylindrical wire hole of the top cover in sequence, and then extends to the outside of the shell.

[0007] Furthermore, in the above-mentioned harmonic tubular acoustic black hole hydraulic pulsation attenuation-energy trapping composite system, the microlattice acoustic metamaterial adopts porosity gradient control (gradually changing from 60% to 20%) along the hydraulic oil flow direction, and its outer surface is coated with a perfluorosilane modified silicone aerogel coating to enhance sound attenuation and hydraulic oil erosion resistance.

[0008] Furthermore, in the above-mentioned harmonic tubular acoustic black hole hydraulic pulsation attenuation-energy capture composite system, the circumferential parts of the upper and lower cover plates both adopt a four-channel neck tube structure design, and each neck tube and its corresponding cavity cooperate to form a Helmholtz resonant unit.

[0009] Furthermore, in the above-mentioned hydraulic pulsation attenuation-energy-harvesting composite system based on the harmonic tubular acoustic black hole, the fitting clearance between the plunger and the cylinder telescopic rod is 0.05mm to 0.1mm, and the mating surface is coated with a polytetrafluoroethylene wear-resistant layer to ensure the accuracy and durability of the cavity volume adjustment.

[0010] By utilizing the gradient porosity attenuation of high-frequency pulsations in microlattice acoustic metamaterials, the focusing of low-frequency pulsations by acoustic black hole septa to enhance piezoelectric corrugated diaphragm deformation, the Helmholtz resonator formed by a four-channel neck tube and cavity to balance static pressure, and the synergistic effect of cylinder adjusting cavity volume to adapt to residual frequency pulsations, high efficiency suppression of multi-frequency pressure pulsations in hydraulic oil and piezoelectric recovery of pulsation energy are achieved, thereby improving the operational stability and energy efficiency of hydraulic systems. This technology is suitable for high-pressure hydraulic systems in fields such as engineering machinery and aerospace.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows.

[0012] For mid-to-high frequency pulsations in the 500-2000Hz range, efficient attenuation is achieved through a stepped porosity microlattice acoustic metamaterial.

[0013] To address low-frequency pulsations, an acoustic black hole channel is used to focus wave energy, driving the piezoelectric corrugated diaphragm to deform and increase voltage output, thus achieving energy recovery. At the same time, a Hector resonator is formed by the four neck tubes of different diameters around the diaphragm and the upper cavity to balance the static pressure. The volume of the cavity is adjusted by a cylinder to eliminate residual low-frequency pulsations. Ultimately, this approach combines multi-frequency pulsation suppression with energy recovery, improving the stability and energy efficiency of the hydraulic system. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0015] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0016] Figure 2 for Figure 1 A magnified view of part A in the middle (showing the microlattice acoustic metamaterial mounting structure).

[0017] Figure 3 for Figure 1 A magnified view of part B in the middle (showing the piezoelectric diaphragm assembly).

[0018] Figure 4 yes Figure 3 Top view (showing the four-channel neck tube layout).

[0019] Figure 5 This is a microstructure diagram of a microlattice acoustic metamaterial. Detailed Implementation

[0020] To make the purpose, technical solution and advantages of this patent clearer, the invention will be further described in detail below with reference to the accompanying drawings.

[0021] Figure 1 This is one embodiment of the present invention, including a three-way pipe joint 1, sealing rings (2, 5, 13-1, 13-4, 15, 16, 17, 18), a housing 3, a damping material 4, a cylindrical partition 6, a grooved cylindrical housing 7, a microcrystalline acoustic metamaterial 8, a gel 9, a titanium alloy support frame 10, an acoustic black hole partition 11, a first resonant cavity 12, a piezoelectric ceramic sheet 13-6, a piezoelectric corrugated diaphragm 13-5, a piezoelectric diaphragm upper cover plate 13-2, a piezoelectric diaphragm lower cover plate 13-3, a second resonant cavity 14, a top cover 20, a plunger 19, and a cylinder 21.

[0022] As shown in Figure 1, the shell 3 has six circumferentially distributed bolt fixing through holes at the top and a cylindrical through hole at the bottom with external threads for connection to the internal thread end of the tee pipe connector 1. The tee pipe connector 1 is connected to the hydraulic system pipeline through this connection to realize the introduction of hydraulic oil. The shell 3 has a layered pressure-bearing design. The middle layer is filled with a damping and vibration-damping layer 4 composed of butyl rubber and lead foil. The inner layer is used to contact the cylindrical partition 6 to achieve sealing oil. The upper and lower end faces of the cylindrical partition 6 are arranged with sealing rings 5 ​​and 16. The outer layer is a stainless steel forging layer.

[0023] As shown in Figure 5, the microlattice acoustic metamaterial 8 adopts gradient control of porosity, from 60% to 20%. The outer circumferential surface of the microlattice acoustic metamaterial 8 is arranged in the groove of the grooved cylindrical shell 7, and perfluorosilane modified silica aerogel 9 is arranged on the surface of the microlattice acoustic metamaterial 8.

[0024] As shown in Figure 1, the acoustic black hole partition 11, the first resonant cavity 12, and the second resonant cavity 14 are positioned in the groove of the titanium alloy support frame 10 by matching the positioning groove on the inner surface of their outer circumferential surface. When the hydraulic oil attenuates the mid-to-high frequency pulsations through the microcrystalline acoustic metamaterial 8, the tubular acoustic black hole structure formed by the titanium alloy support frame 10 and the acoustic black hole partition 11 will focus the low-frequency pulsations in the hydraulic oil onto the surface of the piezoelectric corrugated diaphragm 13-5 due to the gradient impedance design of the acoustic black hole partition 11, thus driving the diaphragm to deform.

[0025] As shown in Figure 3, the piezoelectric module has an upper cover plate 13-2 and a lower cover plate 13-3 of a piezoelectric corrugated diaphragm arranged between the first resonant cavity 12 and the second resonant cavity 14. The piezoelectric corrugated diaphragm 13-5 is tightly pressed between the upper cover plate 13-2 and the lower cover plate 13-3. Eight circumferentially evenly distributed piezoelectric ceramic sheets 13-6 are arranged on the upper surface of the piezoelectric corrugated diaphragm 13-5. The end face of the first resonant cavity 12, which contacts the lower cover plate 13-3, is provided with a groove and sealed by a sealing ring 13-4. The end face of the second resonant cavity 14, which contacts the upper cover plate 13-2, is provided with a groove and sealed by a sealing ring 13-1.

[0026] The plunger 19 inside the second resonant cavity 14 is as follows Figure 1 As shown, the cylindrical surface of the plunger 19, which is in contact with the second resonant cavity (14), is provided with four sealing rings 18.

[0027] Furthermore, in order to allow the wires of the piezoelectric ceramic sheet 13-6 to be led out of the housing 3, through holes for wire lead-out are provided in the first resonant cavity 12, the second resonant cavity 14 and the top cover 20.

[0028] Furthermore, after the microlattice acoustic metamaterial 8, titanium alloy support frame 10, acoustic black hole partition 11, first resonant cavity 12, piezoelectric module 13, and second resonant cavity 14 are sequentially arranged, in order to prevent relative rotation or axial movement of the components, hexagonal bolts are used for fixing through the six bolt fixing holes of the shell 3 and the top cover. Finally, the sealed installation of the entire composite system is achieved.

[0029] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A tuned tubular acoustic black hole hydraulic pulsation attenuation-energy trapping composite system, comprising a shell (3), a three-way pipe joint (1), a microlattice acoustic metamaterial (8), an acoustic black hole partition (11), a piezoelectric corrugated diaphragm assembly (13), and a cavity adjustment mechanism; characterized in that: The shell (3) is a three-layer cylindrical structure, with the middle layer filled with damping material (4); the microlattice acoustic metamaterial (8) is arranged in the grooved cylindrical shell (7), and its porosity decreases from 60% to 20% along the hydraulic oil flow direction; the acoustic black hole partition (11) is installed in the groove of the titanium alloy support frame (10), and together with the piezoelectric corrugated diaphragm assembly (13), it constitutes the acoustic black hole focusing structure; the piezoelectric corrugated diaphragm assembly (13) includes an upper cover plate (13-2), a lower cover plate (13-3), a piezoelectric corrugated diaphragm (13-5), and a piezoelectric ceramic sheet (13-6). The upper cover plate (13-2) and the lower cover plate (13-3) are provided with four-channel neck tubes of different diameters around their circumference, which together with the cavity constitute a Helmholtz resonant unit; the cavity adjustment mechanism includes a plunger (19) and a cylinder (21), and the cavity volume of the second resonant cavity (14) is adjusted by the cylinder extension rod.

2. The system according to claim 1, characterized in that: The inner surface of the titanium alloy support frame (10) is provided with 12 grooves for installing the acoustic black hole partition (11), and the adjacent grooves are hollowed out.

3. The system according to claim 1, characterized in that: The surface of the microlattice acoustic metamaterial (8) is coated with perfluorosilane modified silica aerogel (9).

4. The system according to claim 1, characterized in that: The substrate of the piezoelectric corrugated diaphragm (13-5) is a Hastelloy C276 annular corrugated sheet with a corrugation depth of 0.3 mm and a spacing of 2 mm; the piezoelectric ceramic sheet (13-6) is a PZT-8 fan-shaped ceramic sheet.

5. The system according to claim 1, characterized in that: The clearance between the plunger (19) and the cylinder extension rod of the cylinder (21) is 0.05mm to 0.1mm, and the mating surfaces are coated with a polytetrafluoroethylene wear-resistant layer.

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