Pipeline noise control device and method based on local resonance mechanism acoustic metamaterial

Abstract

The invention discloses a pipeline noise control device based on a local resonance mechanism acoustic metamaterial. The pipeline noise control device comprises a pipeline, a flexible film with pretightening force is embedded in the side wall of the pipeline, a plurality of connecting points are arranged on the flexible film, spring vibrators are arranged on the connecting points, the spring vibrators and the flexible film can generate superposed vibration, and when incident sound excitation reaches a specific frequency, radiation sound waves generated by vibration of the spring vibrators and the flexible film are cancelled with incident sound waves. According to the pipeline noise control device, a brand new design method is adopted, especially, a good control effect on low-frequency noise which is difficult to solve is achieved, and high sound insulation can be achieved at an ultra-low frequency band. The pipeline noise control device is small in number of adopted assemblies and simple in structure, so that the construction period is short, the design effect is remarkable, and certain practical engineering application value is achieved.

Description

technical field [0001] The invention relates to an acoustic metamaterial applying a local resonance mechanism, which is composed of a spring vibrator and a tensioned embedded film. This structural design is applied to the sound insulation and noise reduction of pipelines, and belongs to the field of noise control. Background technique [0002] Piping structures are commonly found in aerospace, industrial production, transportation and other daily life. Acoustic waves in pipes have the characteristics of long propagation distance, small attenuation, and difficult control. It is of great practical significance to study pipe noise reduction. Existing anechoic design applications include the variable-section automobile exhaust pipe that uses the acoustic impedance mismatch mechanism to reflect sound waves, and the pipe acoustic lining that uses damping to dissipate sound energy. However, the variable cross-section design is often cumbersome, and there is a passband, which affe...

AI Technical Summary

Problems solved by technology

This structure is simplified compared with the previous one, but there are still too many additional equipment and the disadvantages of changing the original flow field in the pipe. At the same time, it only targets the first-order noise mode and cannot control the subsequent modes.

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