Underwater sound wave energy collection device

Abstract

The invention provides an underwater sound wave energy collection device, which is characterized in that a middle layer cavity, an upper Helmholtz resonant cavity and a lower Helmholtz resonant cavity are arranged in an outer layer cavity of which the top end is covered by a waterproof sound transmission film; the waterproof sound transmission film is arranged in the outer layer cavity, so that sound waves can enter the upper Helmholtz resonant cavity, the first waveguide area and the second waveguide area after entering the outer layer cavity through the waterproof sound transmission film, and the phases of the sound waves entering the upper Helmholtz resonant cavity and the first waveguide area are the same. The phases of the sound waves entering the second waveguide area change after passing through the labyrinth waveguide, namely the phases of the sound waves contacted with the top surface of the first flexible film and the bottom surface of the second flexible film are the same, the phases of the sound waves contacted with the bottom surface of the first flexible film and the top surface of the second flexible film are the same, and a phase difference exists between the front and rear sound waves; therefore, the first flexible thin film and the second flexible thin film move face to face or back to back at the same frequency, and meanwhile the magnetic sheet and the coil are driven to move along with the first flexible thin film and the second flexible thin film to generate electric energy.

Description

Technical Field

[0001] The present invention relates to the field of novel energy harvesting devices, and in particular to an underwater sound wave energy harvesting device. Background Art

[0002] To monitor radioactive materials in the deep sea, it is necessary to install underwater sensor nodes. These nodes are typically battery-powered, but batteries have limited battery life and are difficult to replace, making them difficult to meet the demand for long-term standby. Furthermore, batteries contain harmful chemicals, and improper handling can cause environmental pollution.

[0003] Because the attenuation coefficient of sound waves propagating in seawater is much smaller than that in air, they can be effectively transmitted over long distances with less energy loss. In addition, with the continuous development of microelectronics technology, the power consumption of microelectronic devices continues to decrease, making it possible to capture sound wave energy from water to power sensor nodes. Summary of the Invention

[0004] The purpose of the present invention is to solve the problem of how to capture underwater acoustic wave energy for power generation. An underwater acoustic wave energy harvesting device is invented. Compared with traditional wired and battery-powered methods, the device has the advantages of low cost, simple structure, flexible deployment, and wide application range.

[0005] The present invention solves the above-mentioned technical problems through the following technical solutions: An underwater acoustic wave energy harvesting device, characterized in that it comprises:

[0006] An outer cavity, the top of which is covered by a waterproof and sound-permeable membrane;

[0007] a middle cavity, disposed in the outer cavity, wherein the middle cavity is flush with the top of the outer cavity, and a first waveguide region is formed between the middle cavity and the outer cavity;

[0008] an inner layer structural unit disposed in the middle layer cavity, the inner layer structural unit comprising an upper Helmholtz resonant cavity and a lower Helmholtz resonant cavity arranged vertically, a first short tube being disposed at the upper end of the upper Helmholtz resonant cavity and a first flexible film being disposed at the lower end, a second flexible film being disposed at the upper end of the lower Helmholtz resonant cavity and a second short tube being disposed at the lower end, a second waveguide region being formed between the inner layer structural unit and the middle layer cavity, the second waveguide region being provided with a labyrinth-type waveguide, the labyrinth-type waveguide being formed between the outer wall of the upper Helmholtz resonant cavity and the inner wall of the middle layer cavity, the upper Helmholtz resonant cavity being not connected to the second waveguide region, and the lower Helmholtz resonant cavity being connected to the first waveguide region via the second short tube;

[0009] A magnetic sheet and a coil, one of which is fixed to the surface of the first flexible film, and the other of which is fixed to the surface of the second flexible film, and the projections of the magnetic sheet and the coil on the horizontal plane at least partially overlap.

[0010] The present invention provides a middle cavity, an upper Helmholtz resonant cavity, and a lower Helmholtz resonant cavity within an outer cavity covered by a waterproof sound-permeable membrane. When the underwater sound wave energy harvester is placed underwater, sound waves enter the outer cavity through the waterproof sound-permeable membrane and can then enter the upper Helmholtz resonant cavity, the first waveguide region, and the second waveguide region. The sound waves entering the upper Helmholtz resonant cavity and the first waveguide region have the same phase, while the sound waves entering the second waveguide region have a phase change after passing through the labyrinthine waveguide. That is, the sound waves contacted by the top surface of the first flexible film and the bottom surface of the second flexible film have the same phase, while the sound waves contacted by the bottom surface of the first flexible film and the top surface of the second flexible film have the same phase, but a phase difference exists between the two. This causes the first and second flexible films to move toward or away from each other at the same frequency, simultaneously driving the magnetic sheet and the coil to move toward or away from each other at the same frequency, thereby generating electrical energy.

[0011] In a preferred embodiment, the labyrinth waveguide is formed by a plurality of partitions arranged in an interlaced manner, so that the phase of the sound wave entering the second waveguide area changes after passing through the labyrinth waveguide.

[0012] Furthermore, the partitions are annular, and a plurality of the partitions are fixed to the outer wall of the upper Helmholtz resonant cavity and the inner wall of the middle cavity in an alternating manner. Alternatively, the plurality of the partitions are integrally formed with the outer wall of the upper Helmholtz resonant cavity and the inner wall of the middle cavity. This arrangement ensures that the sound waves contacted by the bottom surface of the first flexible film and the top surface of the second flexible film are in phase with each other, while having a phase difference with the sound waves contacted by the top surface of the first flexible film and the bottom surface of the second flexible film.

[0013] In a preferred embodiment, the dimensions of the labyrinthine waveguide are designed so that the phases of the acoustic waves input to the upper and lower sides of the first and second flexible membranes are 180° apart. This arrangement maximizes the displacement of the first and second flexible membranes when moving toward or away from each other at the same frequency.

[0014] In a preferred embodiment, the top of the first short tube is flush with the top of the outer cavity, or a separator ring is provided at the upper end of the upper Helmholtz resonant cavity, the top of which is flush with the top of the outer cavity, and the first short tube is located within the separator ring. This arrangement separates the upper Helmholtz resonant cavity from the second waveguide region.

[0015] Furthermore, the upper Helmholtz resonant cavity and the lower Helmholtz resonant cavity are arranged axially symmetrically, so that the projection overlap of the first flexible film and the second flexible film along the symmetry axis is maximized, thereby facilitating the magnet to cut the magnetic lines of force to generate electrical energy.

[0016] Furthermore, the magnetic sheet and the coil are arranged axially symmetrically, and the symmetry axis of the magnetic sheet and the coil coincides with the symmetry axis of the upper Helmholtz resonant cavity and the lower Helmholtz resonant cavity. This arrangement maximizes the electrical energy generated by the magnetic sheet and the coil during their movement toward or away from each other.

[0017] In a preferred embodiment, the central axis of the middle cavity is coincident with or parallel to the central axis of the inner structural unit. This arrangement makes the structure simple and easy to assemble.

[0018] In a preferred embodiment, the top end of the first short tube is flush with the top end of the outer cavity, and the upper and lower Helmholtz resonant cavities are centrally symmetrically arranged. This arrangement provides the upper and lower Helmholtz resonant cavities with identical structures and dimensions, facilitating processing and assembly, and further reducing costs.

[0019] In a preferred embodiment, the magnetic sheet and the coil are both thin sheets, with one of the magnetic sheet and the coil secured to the upper or lower surface of the first flexible film, and the other secured to the upper or lower surface of the second flexible film. This arrangement facilitates a greater relative displacement between the magnet and the coil, thereby improving the efficiency of power generation.

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

[0021] 1. Improve the capture efficiency of acoustic wave energy based on waterproof and sound-permeable membrane and Helmholtz resonant cavity;

[0022] 2. Through the ingenious design of setting up the middle cavity, upper Helmholtz resonant cavity and lower Helmholtz resonant cavity in the outer cavity, the sound waves entering the outer cavity are divided into three regions, and the phase of the sound waves in one of the regions is cleverly changed through the maze-type waveguide;

[0023] 3. Through the ingenious arrangement of the first flexible film and the second flexible film, the phase difference of the sound wave is converted into the same-frequency movement of the first flexible film and the second flexible film towards or away from each other. At the same time, the same-frequency movement of the first flexible film and the second flexible film towards or away from each other is converted into electrical energy through the magnet and the coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0025] Figure 1 is a cross-sectional view of an underwater acoustic wave energy harvesting device provided in Example 1;

[0026] Figure 2 is a cross-sectional view of an underwater acoustic wave energy harvesting device provided in Example 2;

[0027] Figure numerals: 1-outer cavity; 2-waterproof sound-permeable membrane; 3-middle cavity; 4-inner structural unit; 5-upper Helmholtz resonant cavity; 51-first short tube; 52-first flexible film; 53-separation ring; 6-lower Helmholtz resonant cavity; 61-second short tube; 62-second flexible film; 7-maze waveguide; 8-magnetic sheet; 9-coil; 10-partition. DETAILED DESCRIPTION

[0028] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0029] Example 1

[0030] Combine Figure 1As shown, the present invention provides an underwater sound wave energy harvesting device, comprising an outer cavity 1 with a top covered by a waterproof sound-permeable membrane 2, a middle cavity 3 arranged in the outer cavity 1, and an inner structure unit 4 arranged in the outer cavity 1, wherein the middle cavity 3 and the outer cavity 1 are both cylindrical, with tops flush, and central axes coincident, and a first waveguide region is formed between the middle cavity 3 and the outer cavity 1; the inner structure unit 4 comprises an upper Helmholtz resonant cavity 5 and a lower Helmholtz resonant cavity 6 that are axially symmetrical and spaced apart, the upper end of the upper Helmholtz resonant cavity 5 is provided with a separating ring 53 whose top is flush with the top of the outer cavity 1 and a first short tube 51 arranged in the separating ring 53, and a first flexible film 52 is provided at the lower end, the upper end of the lower Helmholtz resonant cavity 6 is provided with a second flexible film 62, and a second short tube 61 is provided at the lower end, and the inner structure unit 4 and the middle cavity 3 are spaced apart. A second waveguide region is formed between the first and second flexible films 52 and 62. The second waveguide region is provided with a labyrinth waveguide 7. The labyrinth waveguide 7 is formed by a plurality of annular baffles 10 arranged at intervals and staggered. The plurality of baffles 10 are integrally formed with the outer wall of the upper Helmholtz resonant cavity 5 and the inner wall of the middle cavity 3. After the sound waves entering the second waveguide region pass through the labyrinth waveguide 7, the phases of the sound waves input to the upper and lower sides of the first flexible film 52 and the second flexible film 62 are 180° different. The lower Helmholtz resonant cavity 6 is connected to the first waveguide region via the second short tube 61. A magnetic sheet 8 is provided on the top surface of the first flexible film 52, and a coil 9 is provided on the bottom surface of the second flexible film 62. The magnetic sheet 8 and the coil 9 are arranged axially symmetrically, and the symmetry axis of the magnetic sheet 8 and the coil 9 coincides with the symmetry axis of the upper and lower Helmholtz resonant cavities 5 and 6.

[0031] When the underwater acoustic wave energy harvester is required to generate electricity, it is ensured that the underwater acoustic wave energy harvester is located underwater. Then, after passing through the waterproof and sound-permeable membrane 2 and entering the outer cavity 1, the acoustic waves can respectively enter the upper Helmholtz resonant cavity 5, the first waveguide region, and the second waveguide region. The acoustic waves entering the upper Helmholtz resonant cavity 5 and the first waveguide region have the same phase, while the acoustic waves entering the second waveguide region undergo a 180° phase change after passing through the labyrinthine waveguide 7. That is, the acoustic waves contacted by the top surface of the first flexible film 52 and the bottom surface of the second flexible film 62 have the same phase, and the acoustic waves contacted by the bottom surface of the first flexible film 52 and the top surface of the second flexible film 62 have the same phase, while there is a 180° phase difference between the two. As a result, the first flexible film 52 and the second flexible film 62 move toward or away from each other at the same frequency, simultaneously driving the magnetic sheet 8 and the coil 9 to move toward or away from each other at the same frequency, thereby generating electrical energy.

[0032] It should be noted that in order to ensure that the phase of the sound wave entering the second waveguide area changes by 180° after passing through the labyrinth waveguide 7, a sound wave generator is required to provide sound waves of corresponding frequency.

[0033] Example 2

[0034] Combine Figure 2 As shown, the structure of this embodiment is basically similar to that of Example 1, except that the middle cavity 3 is cylindrical and has a square cross-section. The middle cavity 3 is parallel to the central axis of the outer cavity 1. The upper end of the upper Helmholtz resonant cavity 5 is provided with only a first short tube 51, and the top of the first short tube 51 is flush with the top of the outer cavity 1. The upper Helmholtz resonant cavity 5 and the lower Helmholtz resonant cavity 6 are arranged in a central symmetric manner. The multiple partitions 10 of the labyrinth waveguide 7 are fixed to the outer wall of the upper Helmholtz resonant cavity 5 and the inner wall of the middle cavity 3 at intervals. The bottom surface of the first flexible film 52 is provided with a coil 9, and the top surface of the second flexible film 62 is provided with a magnetic sheet 8.

[0035] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. An underwater acoustic wave energy harvesting device, characterized in that: include: An outer cavity (1), the top of the outer cavity (1) being covered by a waterproof and sound-permeable membrane (2); A middle cavity (3) is provided in the outer cavity (1), the middle cavity (3) is flush with the top of the outer cavity (1), and a first waveguide region is formed between the middle cavity (3) and the outer cavity (1); An inner layer structural unit (4) is provided in the middle layer cavity (3), and the inner layer structural unit (4) comprises an upper Helmholtz resonant cavity (5) and a lower Helmholtz resonant cavity (6) arranged in an upper and lower manner, a first short tube (51) being provided at the upper end of the upper Helmholtz resonant cavity (5) and a first flexible film (52) being provided at the lower end, a second flexible film (62) being provided at the upper end of the lower Helmholtz resonant cavity (6) and a second short tube (61) being provided at the lower end, a second waveguide region being formed between the inner layer structural unit (4) and the middle layer cavity (3), a labyrinth-type waveguide (7) being provided in the second waveguide region, the labyrinth-type waveguide (7) being formed between the outer wall of the upper Helmholtz resonant cavity (5) and the inner wall of the middle layer cavity (3), the upper Helmholtz resonant cavity (5) not being connected to the second waveguide region, and the lower Helmholtz resonant cavity (6) being connected to the first waveguide region via the second short tube (61); A magnetic sheet (8) and a coil (9), one of the magnetic sheet (8) and the coil (9) is fixed to the surface of the first flexible film (52), and the other of the magnetic sheet (8) and the coil (9) is fixed to the surface of the second flexible film (62), and the projections of the magnetic sheet (8) and the coil (9) on the horizontal plane at least partially overlap.

2. The underwater acoustic wave energy harvesting device according to claim 1, characterized in that: The labyrinth waveguide (7) is formed by a plurality of partitions (10) arranged in an interlaced manner.

3. The underwater acoustic wave energy harvesting device according to claim 2, characterized in that: The partition (10) is annular, and a plurality of the partitions (10) are fixed to the outer wall of the upper Helmholtz resonant cavity (5) and the inner wall of the middle cavity (3) at intervals and in an alternating manner; alternatively, the plurality of the partitions (10) are integrally formed with the outer wall of the upper Helmholtz resonant cavity (5) and the inner wall of the middle cavity (3), respectively.

4. The underwater acoustic wave energy harvesting device according to claim 1, characterized in that: By designing the dimensions of the labyrinth waveguide (7), the phases of the sound waves input to the upper and lower sides of the first flexible film (52) and the second flexible film (62) differ by 180 degrees.

5. The underwater acoustic wave energy harvesting device according to claim 1, characterized in that: The top end of the first short tube (51) is flush with the top end of the outer cavity (1). Alternatively, a separation ring (53) is further provided at the upper end of the upper Helmholtz resonant cavity (5), the top end of the separation ring (53) is flush with the top end of the outer cavity (1), and the first short tube (51) is located inside the separation ring (53).

6. The underwater acoustic wave energy harvesting device according to claim 5, characterized in that: The upper Helmholtz resonant cavity (5) and the lower Helmholtz resonant cavity (6) are arranged in an axisymmetric manner.

7. The underwater acoustic wave energy harvesting device according to claim 6, characterized in that: The magnetic sheet (8) and the coil (9) are arranged in an axisymmetric manner, and the symmetry axes of the magnetic sheet (8) and the coil (9) coincide with the symmetry axes of the upper Helmholtz resonant cavity (5) and the lower Helmholtz resonant cavity (6).

8. The underwater acoustic wave energy harvesting device according to claim 1, characterized in that: The central axis of the middle cavity (3) coincides with or is parallel to the central axis of the outer cavity (1).

9. The underwater acoustic wave energy harvesting device according to claim 1, characterized in that: The top end of the first short tube (51) is flush with the top end of the outer cavity (1), and the upper Helmholtz resonant cavity (5) and the lower Helmholtz resonant cavity (6) are centrally symmetrically arranged.

10. The underwater acoustic wave energy harvesting device according to claim 1, characterized in that: The magnetic sheet (8) and the coil (9) are both in the form of thin sheets, and one of the magnetic sheet (8) and the coil (9) is fixed to the upper surface or the lower surface of the first flexible film (52), and the other is fixed to the upper surface or the lower surface of the second flexible film (62).

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