Acoustic metamaterial based on impedance matching effect and acoustic device

An acoustic metamaterial and impedance matching technology, applied in the field of acoustics, can solve the problem of significant sound wave reflection, and achieve the effect of improving the impedance mismatch problem

Active Publication Date: 2020-08-11
NANJING UNIV
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Based on this, it is necessary to provide an improved acoustic metamaterial for the problem of significant reflection of sound waves on hard boundary materials

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Acoustic metamaterial based on impedance matching effect and acoustic device
  • Acoustic metamaterial based on impedance matching effect and acoustic device
  • Acoustic metamaterial based on impedance matching effect and acoustic device

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0056] This embodiment is a simulation embodiment of the acoustic metamaterial 100 . The following will combine Figure 2 to Figure 4 To further illustrate the impedance matching effect of the acoustic metamaterial 100 of the first embodiment. It should be pointed out that in the simulation, the loss of acoustic waves in the hard boundary material is not introduced.

[0057] figure 2 Figure (a) in Figure 1 shows the incident schematic diagram of Embodiment 1, where the arrow indicates the incident direction of the sound wave (ie the x direction). The microstructure 10 is arranged in sequence along the x direction with 3 Class A thin and hard bounded cylinders, 4 Class B thick and hard bounded cylinders, and 3 Class A thin and hard bounded cylinders, and the microstructure 10 is arranged along the y direction with multiple .

[0058] figure 2 Figure (b) in the figure shows the acoustic wave transmission and reflection curves when the microstructure 10 is arranged in 2 la...

Embodiment 2

[0064] This embodiment is an experimental embodiment of the acoustic metamaterial 100 . The following will combine Figure 5 To further illustrate the impedance matching effect of the acoustic metamaterial 100 of the second embodiment.

[0065] Such as Figure 5 As shown, the impedance matching effect of the acoustic metamaterial 100 is further verified by building an acoustic experiment platform.

[0066] Specifically, a speaker is used as a sound source, and a microphone is used as a receiver. The entire experimental platform is sandwiched by two layers of hard boards, similar to a two-dimensional acoustic waveguide, with a height of 30mm. Surrounded by sound-absorbing sponges to reduce the impact of noise. The sample is prepared from resin by 3D printing technology, the structural size of the microstructure 10 is a=30mm, d=3mm, and the number of cycles in the x direction is set to 2, and the length in the y direction is set to 480mm. Different angles of incidence are a...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides an acoustic metamaterial based on an impedance matching effect and an acoustic device. The acoustic metamaterial comprises a plurality of microstructures, and the microstructures are of a plane symmetrical structure. The microstructures are formed by arranging a plurality of groups of hard boundary material structures with sound wave incident gaps along a preset axis, and the symmetric plane of the microstructures are perpendicular to the preset axis; and the plurality of groups of hard boundary material structures comprise at least two groups of hard boundary material structures with different effective sound speeds. According to the acoustic metamaterial based on the impedance matching effect, incident sound waves can pass through the hard boundary material in a wide working frequency range in a wide-angle and almost non-reflective mode, the problem that impedance of a traditional hard boundary material is not matched is solved, and the application range of some common hard boundary materials in daily life in acoustic engineering is widened.

Description

technical field [0001] The invention relates to the technical field of acoustics, in particular to an acoustic metamaterial and an acoustic device based on an impedance matching effect. Background technique [0002] In the field of acoustics, impedance is a very important topic. Acoustic impedance is generally defined as the product of mass density and sound velocity or the ratio of sound pressure to particle velocity. Acoustic impedance describes the resistance a sound wave encounters as it travels through a material. When a sound wave is incident from one material to another, if there is an impedance difference between the two materials, the reflected wave will inevitably occur, except for the formation of Fabry-Pérot resonance at a specific frequency or at a specific angle (cloth Ruster angle) incident to achieve zero reflection. [0003] In daily life, almost all solid materials (such as glass, resin, plastic, etc.) are acoustic hard boundary materials (abbreviated as...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G10K11/02G10K11/162
CPCG10K11/02G10K11/162Y02T90/00
Inventor 刘晨凯赖耘
Owner NANJING UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap