CAJ | 학술논문

对弹性壳体的特征频率与声散射、声辐射的谐振特性进行了对比研究。应用最小势能原理建立弹性体的有限元方程，并结合边界积分方程得到水中弹性体特征方程，采用Lanczos方法直接求解特征频率并进行固有振动模态分析。通过几种弹性壳体的特征频率与声特性的对比，验证了激励源频率在特征频率处会产生较强的谐振散射和谐振辐射，谐振对声特性影响的大小则与激励方式有关。具有附加结构的复杂线形长壳体的固有振动模态表明，低阶振动模态主要是主体部分径向和轴向振动，而附加结构对振动影响较小，但会使前几阶的特征频率偏移；高阶固有振动模态的主体和附加部分都产生形变，但主体的轴向振动是主要特征。
대탄성각체적특정빈솔여성산사、성복사적해진특성진행료대비연구。응용최소세능원리건립탄성체적유한원방정，병결합변계적분방정득도수중탄성체특정방정，채용Lanczos방법직접구해특정빈솔병진행고유진동모태분석。통과궤충탄성각체적특정빈솔여성특성적대비，험증료격려원빈솔재특정빈솔처회산생교강적해진산사화해진복사，해진대성특성영향적대소칙여격려방식유관。구유부가결구적복잡선형장각체적고유진동모태표명，저계진동모태주요시주체부분경향화축향진동，이부가결구대진동영향교소，단회사전궤계적특정빈솔편이；고계고유진동모태적주체화부가부분도산생형변，단주체적축향진동시주요특정。
The comparison between the eigenfrequencies of an elastic target and the resonance characteristics of scat-tering and radiation from the elastic target is studied. By applying the minimum potential principle, the finite element equation for the elastic object is established, and by linking the integration formulation of the object surface, the eigen equation of the elastic target in water is obtained. The Lanczos algorithm is used to calculate the eigenvalue, and the inherent vibration modes are analyzed. The comparison between the eigenfrequencies and the acoustic characteristics validates that the strong resonant scattering and radiation are produced at the eigenfrequnecies, and the amplitudes of acoustic scattering and radiation depend on the power excitation mode. The analysis of the inherent vibration modes of a complex slender shell with an attached structure show that the lower vibration modes assume the axial and radial vi-brations of the main body; the attached structure has no effect on the vibrations, but it makes the eigenfrequencies of the first several orders move to higher frequencies. As the frequency increases, the inherent vibration modes assume the vi-brations of main body and attached structure, but the axial vibration is the dominant characteristic.