水中双层弹性球壳的回声特性  

Echoes from double elastic spherical shell in water

作　　者：汤渭霖[1] 范军[1] 

机构地区：[1]上海交通大学振动,冲击,噪声国家重点实验室,上海200030

出　　处：《声学学报》1999年第2期174-182,共9页Acta Acustica

摘　　要：研究水中双层同心弹性球壳的声散射．利用严格弹性理论和分离变量法导出了Rnyleigh简正级数解．计算并比较了单层和双层弹性球壳的反向散射形态函数．为了分析回波结构也计算了窄脉冲回波序列．结果表明，外壳很薄内壳稍厚的双层弹性球壳的回波特性主要依赖于内壳。在低Ka时双层壳体的回波可以近似用内部充水的外壳和内部真空的内壳的回波叠加而成．Acoustic scattering by double concentric elastic spherical shell in water is studied. TheRayleigh normal mode solution is derived using exact elastic theory and separation of variables. Thebackscattering form functions of single and double shell were calculated and compared. To analyze echostructure the echo pulse sequence of a narrow incident pulse were also presented. Calculation resultsshow that echo characteristics of double shell constituted by a very thin outer shell and a thicker innershell are dependent mainly on the inner shell. At low ha echoes from double shell can be approximatedby a sum of two echoes one of which is from the outer shell with water filled and the other is from theinner shell with vacuum filled.

关 键 词：水声学 弹性球壳 回声特性 瑞利简正级数解 

分 类 号：O427.1[理学—声学]