舷间充水双层弹性薄球壳结构声辐射研究

Structural-acoustic radiation of elastic thin spheric double-shell with contained water

文章推导了简谐径向集中力作用下舷间充水双层弹性薄球壳振动和水下辐射噪声的解析计算式,可用于数值计算方法的考核验证。在此基础上,以不同结构阻尼下辐射声功率与输入总功率随频率的变化关系为主线展开研究,同时分析了舷间水、外球壳对水下辐射噪声和激励点输入机械阻抗的影响。最后,对采用输入功率流评定结构声辐射大小的方法的适用性提出了一点质疑。

An analytic solution of underwater vibration and acoustic radiation of elastic thin spheric dou ble-shell driven by a harmonic point force in the radial direction is deduced, and it can been used for test- ing and verifying numerical method. On the basis, the variability of radiated power and input total power with frequency at different structural damping, and the effects of the contained water and the outer shell on underwater acoustic radiation and driving-point mechanical impedance are discussed. Finally, a small query for applicability of the method which uses input power flow to assess the magnitude of structural-acoustic radiation is proposed.