【摘要】 从球坐标中声波波动方程出发 ,利用本征函数展开方法和界面边界条件 ,导出了双层弹性封闭球壳的内部散射声场表达式。对于单位源强度的点声源 ,本文计算了分别由弹性 /粘弹性和弹性 /吸声材料组成的双层封闭球壳的内部散射声压随频率的变化关系。计算结果表明 ,粘弹性材料和吸声材料在某些频段对散射声压有十分明显的抑制作用更多还原

【Abstract】 Based on the acoustic wave equation in a spherical coordinate system, the eigenfunction expansion method and interface boundary conditions are used to derive the inside scattered sound field of a double layered elastic enclosed spherical shell in this paper. For a point sound source with unit intensity, the variation of the interior scattered sound pressure of an enclosed double layered elastic/viscoelastic spherical shell versus frequency is calculated. Besides, when a layer of sound absorpting material coveres the interior surface of a spherical shell, the formula for determing the interior scattered sound field is presented. The numerical results indicate that the viscoelastic material and sound absorption material have a very good performance on suppressing the noises of the scattered sound pressure in certain frequency band.更多还原