近水面状态有限长圆柱壳受迫振动的输入功率流和声辐射特性

Research on input power flow and sound radiation from a cylindrical shell immersed near the free surface

基于声固耦合模型,采用波传播方法分析近水面状态有限长圆柱壳受迫振动的输入功率流和声辐射特性,并考虑了自由液面的影响。通过与有限元仿真结果进行对比分析,验证了该方法的正确性。当圆柱壳接近自由液面时,自由液面的存在致使水下圆柱壳输入功率流和声辐射特性的峰值频率向高频偏移,且响应幅值也略有增大。随着潜深的增大,自由液面对圆柱壳输入功率流特性的影响逐渐减小。当潜深大于5倍半径时,自由液面对耦合系统输入功率流的影响可以忽略,但其对耦合系统声辐射特性的影响不可忽略。

The sound-structure interaction model is used to analyze the input power flow and sound radiation characteristics from a cylindrical shell immersed in fluid near the free surface,and the effect of free surface is considered.The accuracy of present method is verified through comparison with the FEM.When cylindrical shell is close to free surface,the existence of free surface will result in the reduction of resonance frequencies.When the immersion depth of shell increases,the influence of free surface will be reduced.Finally,the free surface effect on structure vibration characteristics is negligible,but it will still affect the response level of sound radiation characteristics of coupled system.