CN-121486743-B - Loudspeaker device based on M-H metamaterial and sound propagation method using loudspeaker device

CN121486743BCN 121486743 BCN121486743 BCN 121486743BCN-121486743-B

Abstract

The application provides a sound amplifying device based on M-H metamaterial and a sound propagation method using the same, wherein the sound amplifying device at least comprises an upper shell, a lower shell and a waveguide positioned between the upper shell and the lower shell, and the waveguide is made of Mie metamaterial; the waveguide comprises an outer wall, a plurality of sound wave inlets are formed in the outer wall, a waveguide space is formed by surrounding an upper shell, a lower shell and the outer wall, through holes penetrating the waveguide and the upper shell are formed in the waveguide space, the through holes are sound wave outlets in the sound amplifying device, the waveguide comprises a plurality of fan parts which are circumferentially arranged around the through holes in a radiation mode, a waveguide channel penetrating between the sound wave outlets and the sound wave inlets is formed between every two adjacent fan parts, control current of a sound source is determined by the size of the sound amplifying device and scattering distribution conditions of the sound amplifying device under different resonance modes, sound at the sound wave outlets is larger than sound energy levels at the sound source, and an included angle exists in the propagation direction. By determining the control current at the sound source that is the best match with the size of the loudspeaker, low cost, high accuracy, wide range of application sound propagation control is achieved.

Inventors

ZENG ZHEN
ZHANG MING
REN LI

Assignees

华中科技大学

Dates

Publication Date: 20260505
Application Date: 20260109

Claims (10)

1. An M-H metamaterial-based amplifying device, wherein the amplifying device at least comprises: the device comprises an upper shell, a lower shell and a waveguide positioned between the upper shell and the lower shell, wherein the waveguide is made of Mie metamaterial; the waveguide comprises an outer wall, a plurality of sound wave inlets are arranged on the outer wall, and the upper shell, the lower shell and the outer wall surround to form a waveguide space; a through hole penetrating through the waveguide and the upper shell is arranged in the waveguide space, and the through hole is an acoustic wave outlet in the sound amplifying device; the waveguide comprises a plurality of sectors which are circumferentially arranged in a radiation manner around the through hole; each fan part comprises a radial rib and a plurality of circumferential ribs arranged on two sides of the radial rib, the plurality of circumferential ribs on the same side are arranged at intervals, two groups of circumferential ribs which are opposite to each other on adjacent fan parts are arranged in a staggered way, and the free ends of the circumferential ribs of each radial rib are arranged at intervals relative to the adjacent radial ribs, so that a waveguide channel which penetrates through between the sound wave outlet and the sound wave inlet is formed between the adjacent fan parts; The control current of the sound source is determined by the size of the sound amplifying device and the scattering distribution condition of the sound amplifying device under different resonance modes, the sound at the sound wave outlet is larger than the sound energy level at the sound source, an included angle exists in the propagation direction, the forward and backward scattering ratio of the sound amplifying device is reduced along with the increase of the thickness of the upper shell at the resonance frequency under the monopole resonance mode, the up and down scattering ratio is reduced along with the increase of the height of the upper shell along with the increase of the diameter of the through hole, the width of the waveguide channel is narrower and the regulated sound wave wavelength is larger under the same unit size.
2. The loudspeaker of claim 1, wherein the control current is in a non-linear inverse relationship with the thickness of the upper housing, the length of the waveguide channel, and the height of the loudspeaker, respectively, and the control current is in a non-linear proportional relationship with the diameter of the through hole, respectively, in the same resonant mode.
3. The loudspeaker of claim 1, wherein a first spacing of free ends of the circumferential ribs from adjacent radial ribs is less than a length of the circumferential ribs, the first spacing of the circumferential ribs of a same sector being equal, a spacing of free ends of circumferential ribs furthest from the through hole on each sector from adjacent radial ribs being the sound wave inlet, and a spacing of free ends of circumferential ribs closest to the through hole on each sector from adjacent radial ribs being the sound wave outlet.
4. The loudspeaker of claim 1, wherein the waveguide is a hollow cylindrical structure having a center through which the sound wave inlet and the sound wave outlet have the same height as the waveguide, and the radial rib and the circumferential rib have the same height as the waveguide.
5. The loudspeaker of claim 1, wherein said radial ribs isolate adjacent said waveguide channels, each of said sectors comprising one of said waveguide channels, each of said sectors having the same area and each of said waveguide channels having the same channel width.
6. A sound propagation method using a loudspeaker device according to any one of claims 1-5, characterized in that the method comprises: adjusting the control current of the sound source according to the size of the sound amplifying device; And placing the sound amplifying device on a sound propagation path, outputting sound from the sound amplifying device, wherein an included angle exists between the sound amplifying device and the direction of inputting the sound amplifying device, and the energy value is increased, and the increasing amplitude of the energy value is related to the control current value.
7. The method of claim 6, the adjusting the control current of the sound source according to the size of the loudspeaker device, comprising: Determining the thickness of an upper shell of the sound amplifying device, the length of the waveguide channel, the height of the sound amplifying device and the diameter of the through hole; Calculating a ratio between a square of the diameter of the through hole and a thickness of the upper case; Calculating the sum of the ratio and the derivative of the diameter of the through hole; calculating a first product of the sum and the loudspeaker height; Determining a resonant frequency from a product of an evolution value of the first product and a length of the waveguide channel; And adjusting the control current of the sound source to be the optimal control current according to the optimal control current of the sound source matched with the resonance frequency.
8. The method of claim 6, the placing the loudspeaker device on a sound propagation path, comprising: performing univariate test on the amplifying device to obtain the association relation between the sound transmission performance of the amplifying device and the mounting azimuth of the amplifying device; And determining the receiving azimuth of the sound, and determining the placement position of the sound amplifying device on the sound propagation path according to the receiving azimuth and the association relation, wherein an included angle exists between a connecting line between the receiving azimuth and a sound outlet of the sound amplifying device and a local sound propagation path between a sound source and the sound amplifying device, and the energy level of the sound at the receiving position is higher than that of the sound at the emitting position.
9. The method of claim 8, the performing a univariate test on the loudspeaker device comprising: performing a univariate comparison experiment on the pointing characteristic process of the sound amplifying device, wherein the univariate comprises at least the azimuth of the sound amplifying device relative to a sound source and the distance of the sound amplifying device relative to the sound source; calculating directivity parameters according to sound intensity ratios of different dimensions under single variables; and according to the directivity parameter evaluation test result, determining the relation between the sound source energy level change condition and the arrangement azimuth and distance of the sound amplifying device respectively according to the evaluation result.
10. The method of claim 9, wherein the calculating directivity parameters from the sound intensity ratios of different dimensions under a single variable comprises: in a univariate test of azimuth, calculating directivity parameters according to the ratio of sound intensity in a specific direction to sound intensity in an omnidirectional direction; In the range univariate experiment, the directivity parameters are calculated from the ratio of the sound intensity of the sound source in the far field to the sound intensity emitted by the omnidirectional sound source of the same intensity in the two-dimensional case.

Description

Loudspeaker device based on M-H metamaterial and sound propagation method using loudspeaker device Technical Field The application relates to the technical field of sound amplification, in particular to a sound amplifying device based on M-H metamaterial and a sound transmission method using the sound amplifying device. Background Sound propagation is ubiquitous in life, for example, electromagnetic speakers such as mobile phones, computers, sound equipment, etc. or moving-coil speakers can be regarded as a sound source, and the sound propagates through a medium to reach a predetermined sound receiving place. During the sound propagation, there is a reduction in energy level, and the heard sound has different levels of energy level loss, so that clear sound content cannot be obtained. In recent years, the application of the super-structure material in the sound wave regulation and control scene has greatly progressed in scientific research, and development of novel acoustic elements by utilizing the ultra-conventional acoustic specific effect is also attracting attention. However, due to the defects of high loss, complex structure, limited specific properties and the like of the traditional super-structure material, the design of the acoustic super-structure material still has a plurality of challenges, and the effective regulation and control of the large-wavelength low-frequency sound wave by the micro-unit size structure is a difficult problem in acoustic research. In addition, the structure of the super-structure material directly influences the resonance effect, the control effect of the traditional super-structure material structure on the sound wave is poor, the super-structure is usually manually determined to be placed according to experience or a trial and error mode, and the direction and energy of the sound wave cannot be accurately regulated. Furthermore, in the prior art, the amplifying device is designed according to a specific application scenario, that is, all parameters of the sound source are well defined, for example, a current frequency value and a current magnitude of the electromagnetic speaker are well defined, and therefore, frequency and energy level of sound are well defined. Disclosure of Invention In view of this, the application provides a sound amplifying device based on M-H metamaterial and a sound propagation method using the same, which are used for adjusting the current frequency at the sound source according to the size information of the sound amplifying device, so that the sound amplifying device with the same structure can be adapted to the sound regulation and control under various scenes, and the directivity and energy level of the sound can be adjusted with low cost and high adaptability. Specifically, the application is realized by the following technical scheme: According to a first aspect of the application, there is provided a loudspeaker device based on M-H metamaterial, the loudspeaker device comprising at least: the device comprises an upper shell, a lower shell and a waveguide positioned between the upper shell and the lower shell, wherein the waveguide is made of Mie metamaterial; the waveguide comprises an outer wall, a plurality of sound wave inlets are arranged on the outer wall, and the upper shell, the lower shell and the outer wall surround to form a waveguide space; a through hole penetrating through the waveguide and the upper shell is arranged in the waveguide space, and the through hole is an acoustic wave outlet in the sound amplifying device; the waveguide comprises a plurality of sectors which are circumferentially arranged in a radiation manner around the through hole; each fan part comprises a radial rib and a plurality of circumferential ribs arranged on two sides of the radial rib, the plurality of circumferential ribs on the same side are arranged at intervals, two groups of circumferential ribs which are opposite to each other on adjacent fan parts are arranged in a staggered way, and the free ends of the circumferential ribs of each radial rib are arranged at intervals relative to the adjacent radial ribs, so that a waveguide channel which penetrates through between the sound wave outlet and the sound wave inlet is formed between the adjacent fan parts; the control current of the sound source is determined by the size of the sound amplifying device and the scattering distribution condition of the sound amplifying device under different resonance modes, the sound at the sound wave outlet is larger than the sound energy level at the sound source, and an included angle exists in the propagation direction. A second aspect of the present application provides a sound propagation method based on the loudspeaker device provided in the first aspect, the method comprising: adjusting the control current of the sound source according to the size of the sound amplifying device; And placing the sound amplifying device on a sound propagation path, outp