Gradient slitting double-porosity sound absorbing device and application thereof

A sound-absorbing device and double-porosity technology, which is applied in the directions of sound-producing equipment, instruments, floors, etc., to achieve the effect of enhancing low-frequency sound absorption performance, good sound absorption performance, and excellent sound absorption performance

Active Publication Date: 2019-05-03
XI AN JIAOTONG UNIV
View PDF6 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The above two methods of sound-absorbing panels are difficult to maintain good sound-absorbing performance in the whole frequency band

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
  • Gradient slitting double-porosity sound absorbing device and application thereof
  • Gradient slitting double-porosity sound absorbing device and application thereof
  • Gradient slitting double-porosity sound absorbing device and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0043] see figure 1 and figure 2 , periodically open gradient slots in a perforated porous material plate 1 with a total height of 60mm, the porosity of the base porous material is 90%, and the flow resistance is 47700N·s / m 2 , the viscous characteristic length is 24 μm, the thermal characteristic length is 200 μm, and the tortuosity is 1.29; the slit widths at both ends of the gradient slit are 22 mm and 2 mm respectively, the slit type is trumpet-shaped, the slit edge is an arc, and the slope of the slit edge is in the presence of sound waves Continuously increasing in the direction, the slit rate on the sound-absorbing panel (the total volume of slits accounted for the total volume of the panel without slits) is 16.68%; the side of the end face with the smallest slit width of the perforated porous material plate 1 is placed on the rigid backing In order to simulate the situation where the designed sound-absorbing material is attached to the interior wall, the wall of the ...

Embodiment 2

[0046] The trumpet-shaped seam in Example 1 is changed to a tapered seam, the seam edge is a straight line, and the slope of the seam edge remains unchanged in the direction of sound wave incidence, while the seam width and other structural parameters at both ends of the gradient seam, and the porous material of the substrate The material parameters remain unchanged relative to Example 1. At this time, the slit rate of the sound-absorbing panel is 24%; The sound-absorbing material is closely attached to the indoor wall, the wall of the transportation vehicle and the inner wall of the machine. The sound absorption coefficient of embodiment 2 is referring to image 3 . Compared with a uniform porous material plate without slits of the same base material and the same thickness, the structure of this embodiment can appear the sound absorption peak earlier at the frequency of 960 Hz, and achieve enhanced sound absorption in the range above 580 Hz.

[0047] Comparing Example 1 and...

Embodiment 3

[0049] Set the slit widths at both ends of the gradient slit in Example 1 to 6 mm and 2 mm, and select the slit type as trumpet type. Other structural parameters and base porous material remain unchanged, and the placement method is also unchanged. At this time, the slit rate is 7.3%. . The sound absorption coefficient of embodiment 3 is referring to Figure 4 . Compared with the uniform porous material plate without slits of the same base material and the same thickness, the structure of this embodiment can appear the sound absorption peak earlier at the frequency of 550 Hz, and achieve enhanced sound absorption in the range above 290 Hz.

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

PropertyMeasurementUnit
heightaaaaaaaaaa
porosityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a gradient slitting double-porosity sound absorbing device and application thereof. The gradient slitting double-porosity sound absorbing device comprises a seamed porous material plate and rigid backing; the seamed porous material plate is arranged on the rigid backing, a plurality of gradient slits are formed in the seamed porous material plate periodically at intervals,and the slitting direction of the gradient slits is perpendicular to the seamed porous material plate. The gradient slitting double-porosity sound absorbing device is simple and practical in structure, has a superior sound absorbing property and a flexible sound absorbing adjusting function in a low frequency band, a medium frequency band and a high frequency band, and has good and wide application prospects.

Description

technical field [0001] The invention belongs to the technical field of building materials, and in particular relates to a gradient slit double-porosity sound-absorbing device and its application. Background technique [0002] The existing sound-absorbing panel is a plate-shaped material with sound-absorbing and noise-reducing functions, and is mainly used in scenes such as concert halls, museums, libraries, and inner walls of vehicles. Traditional sound-absorbing panels mainly absorb sound in two ways: one is to use porous fibers or foam materials for sound absorption, and the sound absorption coefficient increases with the increase of frequency, which is suitable for high-frequency sound absorption; the other is to use The micro-perforated plate of the cavity is used for sound absorption, which can have resonance sound absorption peaks at lower frequencies, and is suitable for middle and low frequency sound absorption. It is difficult for the above two methods of sound-abs...

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
Patent Type & Authority Applications(China)
IPC IPC(8): E04B1/82E04B1/86G10K11/162
Inventor 辛锋先刘学伟马晓文
Owner XI AN JIAOTONG 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