阻尼层对水下圆柱壳辐射声场的去耦特性影响

摘要

Based on modal superposition method, a model of vibration and sound radiation of underwater cylindrical shell with viscoelastic damping layer is established. In this model, the behavior of the damping layer is described with Navier equation. Numerical results of this model are obtained. The decoupling characteristic of the viscoelastic damping layer to the sound radiation field of the underwater cylindrical shell is investigated by analyzing the mean square velocity of radial vibration and the sound radiation power of the cylindrical shell. The results show that the frequency response curve of the mean square velocity of the radial vibration of the viscoelastic damping layer can be divided into three intervals according to the frequencies. Only in the interval of significantly high frequencies, the sound radiation power can be reduced by the viscoelastic damping layer. Thickness of the damping layer has larger influence on the decoupling effect than the thickness of the shell does.%基于模态叠加法，采用Navier方程描述阻尼层，建立敷设粘弹性阻尼层的水下圆柱壳振动声辐射模型。与数值计算结果比对，验证了计算模型的可靠性。分析圆柱壳的径向均方振速和辐射声功率，研究了粘弹性阻尼层对水下圆柱壳辐射声场的去耦特性影响。结果表明，粘弹性阻尼层的径向均方振速频响曲线可以分作三个频段，当频率较高时，粘弹性阻尼层能降低辐射声功率；与壳体厚度相比，阻尼层厚度对阻尼层去耦特性的影响更大。