机械和螺旋桨振动噪声作用下的物探船水下辐射噪声数值预报

Underwater Noise Numerical Prediction of Seismic Survey Vessel Considering Mechanical and Propeller Vibro-noise

文章探讨机械噪声与螺旋桨噪声共同作用下的物探船水下辐射噪声有效计算方法,采用基于结构有限元-声学边界元的声固耦合模式对水下总辐射的噪声级进行一体化计算。建立某物探船的整船三维结构有限元模型以及流体声学边界元模型。在船体总振动响应分析基础上,将螺旋桨噪声以点声源的形式与机械振动源同时输入统一声学环境中求解,对物探船水下辐射噪声进行数值预报,给出物探船辐射噪声指向特性,并比较2类噪声源一体化计算方法与直接叠加合成方法对物探船水下辐射噪声计算结果的影响。研究表明,工程精度上可接受机械噪声与螺旋桨噪声直接叠加合成总辐射声级的方法,但一体化计算是更合理的处理方式。

A sort of efficient method to calculate seismic survey vessel overall underwater radiation noise which considering mechanical and propeller noise simultaneously are deeply discussed. The noise level calculating is directly based on FEM-IBEM of vibro-acoustic coupling model. A three-dimensional FE model of the seismic survey vessel and fluid acoustic BE model are established. Based on the hull global vibration analysis, the hull mechanical vibration source is imported into the integrative solving acoustic environment together with the propeller noise by the form of a point source. Then underwater radiation noise of the seismic survey vessel is predicted and its directivity characteristics is given out, comparing the calculation differences between two noise source integrated calculation method and direct superposition synthesis method. The results show that the method of synthesizing the total radiated sound level directly by superposition of mechanical noise and propeller noise is acceptable in precision engineering, but the integrated calculation method is more reasonable and efficient.