Mechanical impedance plate composite porous elastic tube sound absorbing structure

Abstract

The invention provides a mechanical impedance plate composite porous elastic tube sound absorbing structure composed of a plurality of sound absorbing units connected in parallel. Each sound absorbing unit comprises a rigid support, a support plate, an elastic tube and a mechanical impedance plate. The rigid support is mounted on a wall surface. The support plate is welded on the rigid support. The elastic tube is pasted between the support plate and the mechanical impedance plate. A gap is arranged between the mechanical impedance plate and the rigid support. The wall surface, the elastic tube, mechanical impedance plate and rigid support define an airtight resonant cavity. The elastic tube is a hollow tube made of viscous-elastic material and the wall surface has no holes. The mechanical impedance plate composite porous elastic tube sound absorbing structure is small in overall structure space. Theoretical analysis and experimental verification show that the mechanical impedance plate composite porous elastic tube sound absorbing structure can widen a sound absorption band at low frequency, can be combined with other sound absorbing structures such as micro perforated plates so that the composite structure has a good sound absorption effect from low frequency to medium frequency.

Description

technical field [0001] The invention relates to the technical field of noise control, in particular to a mechanical impedance plate composite porous elastic tube sound absorption structure. Background technique [0002] One of the key technologies of noise control is the absorption of sound waves in the process of propagation. Sound absorption and noise reduction are frequently used technical measures in many fields such as construction, vehicles and transportation, which require good sound-absorbing structures or sound-absorbing materials. At present, the commonly used micro-perforated plate suction structure and fiber sound-absorbing materials have good sound-absorbing effects at medium and high frequencies, but at low-frequency sound absorption, the thickness of the structure or material needs to be increased, which takes up a lot of space, otherwise the sound-absorbing effect is not good. The traditional sound-absorbing structure of mechanical impedance plates can produc...

AI Technical Summary

Problems solved by technology

The damping coefficient and elastic coefficient of the mechanical impedance are properly controlled, and it can have a high sound absorption peak at low frequencies, and the thickness of the structure is thin, but its sound absorption bandwidth is low. How to broaden the sound absorption frequency band is a current technical problem.

Images