Bamboo shoot spiral imitating bidirectional low-frequency sound absorption metamaterial and additive manufacturing method thereof

Abstract

The invention belongs to the related technical field of acoustic metamaterials, and discloses a bamboo shoot spiral imitating bidirectional low-frequency sound absorption metamaterial and an additive manufacturing method thereof, the metamaterial comprises a plurality of unit cells, and the plurality of unit cells are arranged in an array; each unit cell is provided with a first spiral cavity and a second spiral cavity which are mutually intertwined, one end of each first spiral cavity and one end of each second spiral cavity are both closed, and the other ends of the first spiral cavities and the second spiral cavities are both communicated with outside air. One end, communicated with outside air, of the first spiral cavity and one end, communicated with air, of the second spiral cavity are respectively positioned at two opposite ends of the unit cell; meanwhile, the first spiral cavity and the second spiral cavity are each of a bionic structure of a spiral cavity in a bamboo shoot spiral shell. The two spiral cavities are coupled in a limited space, the length of the resonant cavity is effectively increased through the spiral cavities, low-frequency sound absorption can be achieved under the condition that the size is far smaller than the size of the working wavelength, and the low-frequency sound absorption effects in two directions can be achieved through the two coupled cavities respectively.

Description

technical field

[0001] The invention belongs to the technical field of acoustic metamaterials, and more particularly, relates to a bidirectional low-frequency sound-absorbing metamaterial like bamboo shoots and snails and an additive manufacturing method thereof. Background technique

[0002] Noise widely exists in all areas of life. Long-term exposure to high-intensity noise will cause serious damage to human health. Therefore, it is necessary to reduce noise to provide a more comfortable environment. Traditional sound-absorbing materials such as sponges have a strong dissipation effect on the energy of sound waves due to the large number of micropores in them, and have a good effect of absorbing medium and high frequency noise. However, for low-frequency noise, the energy dissipation coefficient is very low, and traditional porous materials are difficult to absorb, and sound insulation materials obey the law of sound insulation quality, and it is difficult to effectively b...

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