【作者】 陈锐；

【导师】 石仲堃；

【作者基本信息】 华中科技大学 ， 船舶与海洋结构物设计制造， 2005， 硕士

【摘要】 本文在分析了结构声辐射问题的发展历史和研究现状的基础上,从理论、方法和应用技术等方面对振动声辐射问题进行了深入系统的研究。详细地推导出振动声辐射问题的边界积分方程计算公式,并对声辐射边界积分方程计算过程中,解的不唯一性问题进行了研究,指出CHIEF方法是解决积分方程解不唯一性问题有效而可靠的方法。本文根据有限元软件ANSYS和边界元软件SYSNOISE的特点,将两者有机结合起来,数值计算研究了单层壳体结构潜艇的声辐射问题。先利用有限元软件ANSYS计算潜艇结构和外部流体介质的耦合振动,得到耦合振动的节点位移响应值。将位移响应数据转换为速度响应数据后,再利用边界元软件SYSNOISE计算了壳体表面节点处的声压值。同时可得到壳体表面的辐射声功率和辐射效率等声学量。本文分析计算了单层壳体结构潜艇在单点简谐激振力作用下产生的结构振动和声辐射特性。改变激振力的频率和位置进行计算,并对计算结果进行了分析,得到的结果能反映激振频率及激振位置对声压的影响。详细分析了壳体振速曲线与潜艇结构阻抗的关系,计算得出了潜艇结构辐射效率的特性。本文对潜艇结构振动声辐射特性的研究具有重要的意义。本文给出的结论对于潜艇噪声预报,降低潜艇的噪声具有一定的指导意义。更多还原

【Abstract】 In this dissertation, the numerical computation for the acoustic radiation problem(ARP) is studied deeply and systematically in the theory, method and the application technique, based on analyzing the phylogeny and situation of the home and abroad on the numerical computation for the acoustic radiation problem. The calculating formulas of the boundary element method(BEM) for the exterior acoustic radiation problem in the full-space and half-space are deduced, based on the wave propagation theories. The arising of the non-unique solutions, which is associated with the application of the boundary integral equation(BIE) in acoustic radiation problem is analyzed. The Combined Helmholtz Integral Equation Formulation(CHIEF) is proved to be a effectual and reliable method that can overcome the non-uniqueness problem. The numerical analyses of vibration and acoustic radiation from single-shell submarine is carried out by using FEM software ANSYS and BEM software SYSNOISE. First, the coupled-vibration of the shell and water is calculated and the displacement of the nodes is obtained. Then, by transferring the mesh of the single-shell and the displacement values on the nodes into software SYSNOISE, the sound pressure,the radiated sound power and the radiant efficiency are carried out by SYSNOISE. The characteristics of vibration and acoustic radiation from single-shell submarine is analyzed. The results can reflect the relationship between the sound pressure and the stimulating force. The relationship between the structural damp and the average square velocity is analyzed. The characteristics of the radiation efficiency is carried out. The research work in this paper is valuable for investigation of the vibration and acoustic radiation of the submarine. The conclusion of the paper can be use to predict the acoustic radiation of the submarine and reduce the sound pressure.更多还原