基于映射声无限元法柱壳振动声辐射特性分析

Analysis of the Acoustic-Vibration Characteristics of Cylindrical Shells Based on the Mapped Acoustic Infinite Element Method

基于径向形函数可任意变阶的映射声无限元法,对加筋双层圆柱壳的振动声辐射特性进行分析。取无限长圆柱壳体为研究对象,基于映射声无限元法,通过数值计算法对其辐射声场进行研究分析;并将其数值结果与解析解进行对比分析,结果显示二者吻合较好,验证了本文方法的可行性,同时发现此方法具有计算精度好、效率高等优点。在此研究基础上,基于映射变阶声无限元法,对加筋双层圆柱壳的内壳振动特性和远场声辐射特性进行分析,分别讨论内外壳厚度、型材尺寸和托板厚度对加筋双层圆柱壳内壳体表面振动均方加速度级及远场辐射声压级的影响,其分析结果表明,内壳厚度结构参数对其内表面振动均方加速度级及远场辐射声压级的影响最明显。

This paper adopts the mapped variable acoustic infinite element method to analyze the acoustic-vibration characteristics of stiffened double cylindrical shells. First,the sound radiation pressure of aninfinitely long cylinder is obtained via numerical analysis with the mapped acoustic infinite element method. The numerical results agree well with the analytic solutions,which proves the validity and precision ofthe method. Based on the mapped acoustic infinite element method,the paper then analyzes the stiffeneddouble cylindrical shell＇s vibration and far-field underwater noise characteristics,where the effects of theouter shell and inner shell thickness,plate thickness,ring-stiffener＇s dimension on the mean-square acceleration level of surface shell vibration and the influence on the far field sound pressure level of radiationare discussed. The results show that the vibration of inner-shell thickness has the greatest influence on theabove mentioned parameters.