摘要
利用Hankel变换和传递矩阵方法,推导了点激励敷设柔性层系的无限大薄板的辐射声压插入损失和辐射声功率插入损失。理论分析指出,当钢板的质量较大或者频率较高时,柔性层系对于板本身的减振效果实际上很小,辐射噪声降低的主要原因是柔性层系的隔振或隔声作用。辐射声压插入损失与通常所理解的两边都是水时覆盖层的透声系数(及相应的隔声量)没有简单的关系。数值计算表明:(1)低频段存在一个失效区,辐射噪声不降反升;(2)柔性层的损耗越大插入损失提高越多;(3)阻抗渐变的柔性层系的敷设顺序引起的插入损失不同,但均比单层结构有更好的降噪效果。
Radiation pressure insert loss and radiation power insert loss of a point-excited infinite plate covered with multiple compliant layers are provided using Hankel transformation and transfer matrix. Theoretical analysis shows that vibration reduction caused by compliant layers is little when the mass of plate is larger or the frequency is higher, the chief reason of noise reduction is vibration isolation or sound insu- lation by multiple layers.Radiation pressure insert loss is not related simply with transmission coefficient （or sound transmission loss） of multiple layers immersed in water. Calculation results show that： （1） radia- tion noise increases after plate covered layer at low frequency, （2） the higher dissipation of layer is, the more insert loss is, （3） different covering sequence of multiple layers whose impedan to different insert loss, but both can reduce much more noise than single layer. ces vary gradually leads
出处
《船舶力学》
EI
北大核心
2010年第4期421-429,共9页
Journal of Ship Mechanics
基金
上海交通大学海洋工程国家重点实验室自主研究课题基金资助项目(GKZD010014)
关键词
去耦层
传递矩阵
插入损失
decoupling layer
transfer matrix
insert loss
