A low-frequency sound absorbing material with subwavelength thickness

作者：Chen, Changru; Du, Zhibo; Hu, Gengkai^*; Yang, Jun

来源：Applied Physics Letters, 2017, 110(22): 221903.

DOI：10.1063/1.4984095

• SATURATED POROUS-MEDIA
• ACOUSTIC METAMATERIALS
• ABSORPTION
• WAVES
• FLOW
• METASURFACE
• PROPAGATION
• TORTUOSITY
• PERFECT
• AIR

We propose a sound absorbing material efficient for low frequency. This material is mainly composed of two axially coupled tubes in series, which are co-planarly coiled in a plane perpendicular to incident waves. By carefully designing the geometric parameters of the coupled tubes, we can overlap the absorption coefficient curves of each individual tube and are therefore able to broaden the frequency bandwidth within which the absorption coefficient is larger than a designed value. A material with an absorption coefficient greater than 0.8 over a frequency bandwidth of 36 Hz for a low frequency of around 100 Hz can be designed, and the wavelength to thickness ratio reaches as high as 38.5. The experiment measurement with the sample made by the 3D printing technique is also conducted to validate the proposed design method. This work may stimulate the research studies on and applications for low frequency sound absorption. Published by AIP Publishing.

• 出版日期2017-5-29
• 单位北京理工大学