含椭圆柱型空腔的声学覆盖层的吸声特性研究

Absorption characteristics of anechoic coating embedding elliptic-cylinder cavities

摘要:

为进一步探索空腔谐振的吸声机理,研究了以钢板和空气为背衬的含椭圆柱型空腔的声学覆盖层的吸声特性.运用有限单元法对单空腔结构的覆盖层和混合型空腔的覆盖层的吸声性能进行了计算.结果表明,在相同穿孔率的情况下,含椭圆柱型空腔的覆盖层相对含圆柱型空腔的覆盖层具有更低的谐振频率,且扁率越大,谐振频率越低.含椭圆柱型空腔的覆盖层更具有一般性和优化空间,这符合覆盖层消声频率向宽频方向发展的要求.

Abstract:

To further explore the absorption mechanism of cavity resonance,the absorption characteristics of anechoic coating embedding elliptic-cylinder cavities with steel plate and air backing were studied.Based on finite element method,the absorption characteristics of both single-cavity coating and mix-cavity coating were obtained respectively.The results show that the anechoic coating embedding elliptic-cylinder cavities has lower resonant frequencies than anechoic coating embedding cylinder cavities under the same perforated rate.And the bigger the oblateness,the lower the resonant frequencies.On the whole,mix-cavity coating has better absorption characteristics at all frequencies.