赝随机扩散体吸声性能的理论分析  

Theoretical analysis about sound absorption produced by pseudostochastic diffusors

作　　者：赵松龄[1] 盛胜我[1] 

机构地区：[1]同济大学声学研究所

出　　处：《声学学报》1996年第4期555-564,共10页Acta Acustica

摘　　要：本文对赝随机扩散体的吸声性能提出了一个新的分析理论，该理论中假定相邻闭管管口间的声压一般并不保持相等，引入了“耦合声阻抗率”的概念来反映相邻闭管间的声耦合。文中分析了管口附近区域的振速场和声压场，获得了一阶近似的精确解。在这基础上，导出了严格的非线性耦合声阻抗率理论计算公式。典型的数值计算表明，即使在入射声压级并不很高时，非线性耦合声阻率仍可明显地提高共振吸声系数并展宽有效吸声频率范围，从而可以较圆满地解释赝随机扩散体的吸声规律。In this paper, a new theory about sound absorption by pseudostochastic diffusors is proposed.A quantity ."coupling specific acoustic impedance" is introduced, which represents coupling between adjacent wells of the structure. The variation of particle velocity and sound pressure in the vicinity of the opening of wells is investigated and the exact solution of the lst approach is derived. Moreover, the nonlinear effect is discussed. The rigorous formula to calculate the nonlinear coupling specific acoustic impedance is derived. Typical calculation shows the nonlinear effect can apparently improve the sound absorption character of the structure even if the sound pressure level of incident wane is medial.

关 键 词：吸声 声扩散体 

分 类 号：O422.4[理学—声学]