水下圆柱壳结构表面振速插值方法及其辐射声场预测  

An interpolation method for the measured velocity and its application in the prediction of acoustic radiation of submerged cylindrical shell structures

作　　者：吴海军[1] 张一麟[1] 蒋伟康[1] 

机构地区：[1]上海交通大学机械系统与振动国家重点实验室振动冲击噪声研究所,上海200240

出　　处：《声学学报》2015年第5期631-638,共8页Acta Acustica

基　　金：国家自然科学基金(11074170)资助

摘　　要：提出一种圆柱壳表面速度的全局插值算法,表面速度函数周向采用Fourier级数、轴向采用分段Lagrange函数表示,利用圆柱壳结构表面有限位置处的测量数据,计算得到速度函数的级数展开式系数,然后对表面其它位置处的振速进行插值,避免了传统的局部插值和离散产生的误差。数值算例验证了该插值方法能通过有限点位置处的数据,获取连续光滑的表面速度分布,并能满足圆柱壳辐射声场预测的需求。进而,在实验条件下,使用该插值方法对双层圆柱壳水下辐射声场进行了预测,实验结果表明通过该插值方法得到壳体表面速度分布,利用快速边界元方法计算得到的预测声场与实测声场有很好的一致性,验证了该插值方法在圆柱壳辐射声场预测中的正确性和工程适用性。An interpolation method is proposed for the surface velocity of cylindrical shell structures. The surface velocity is expressed by the Fourier series in the circumferential direction and the piecewise Lagrange function in the radial direction. The coefficients of the series expression are computed from few measured surface velocity. Once the coefficients are obtained, the series expression can be used to calculate the velocity at other positions on surface of the cylindrical shell structures which can avoid the errors of conventional interpolation methods and errors caused by discretization. Numerical examples demonstrate that the interpolation method can get smooth velocity distribution on the surface which is satisfactory for predicting the acoustic radiation based on few measured surface velocity. Finally, the accuracy and applicability of the interpolation method for the prediction of acoustic radiation from cylindrical shell structures are experimentally validated.

关 键 词：双层圆柱壳 辐射声场 插值方法 结构表面 预测 振速 水下 FOURIER级数 

分 类 号：O427[理学—声学]