中文摘要：

文章基于有限元／边界元方法计算了双层圆柱壳空气中的固有模态以及在水下激励力作用下的振动与声辐射响应，分析了内外壳振型的相似性，提出用相似性系数来描述振型的相似程度。最后分析了不同轴向位置处的内外壳响应相似程度，得出了一些结论：双层壳内外壳具有很强的相似性；实肋板处的相似性更好。本文为潜艇实验测点布置位置的研究提供了一定的理论根据，具有一定的实用价值。

英文摘要：

FEM/BEM is used to analyze intrinsic modes in air and vibration and sound radiation of the double cylindrical shell in water under force excited state. The similarity coefficient is proposed to describe the similarity between inner and outer shells of double cylindrical shell. Finally, the similarity coefficient between inner and outer shells of double cylindrical shell at various axial positions is analyzed and calcu- lated, and some useful conclusions are drawn： there is a good similarity between inner and outer shells of double cylindrical shell, the similarity at the position of solid floors is better than others. This paper provides some theoretical basis for arranging measuring-point in submarine experiment, which has a certain practical value.