OOFEM Based Research On The Performance Of Coatings For Acoustic Insulation And Vibration Decoupling

Laying Coatings for Acoustic Insulation and Vibration Decoupling is a useful method for decreasing sound radiation of submarine hull. In this paper, the acoustic performance is studied by the Object-Oriented Finite Element Method (OOFEM).Some of the experimentally measured material parameters can not be set in the general finite element software, and most of the existing finite element software is developed using poorly extensible programming. In order to overcome such limitations, the merits of VC++ \FORTAN\ANSYS/APDL\Matlab are integrated to one acoustic simulation software which includes steps of modeling\solution\post analysis. All the processing are made on one platform, with a simple interface, good scalability, fast calculation speed and so on.In this paper, the plannar muti-layered periodic structures are mainly studied, which are symmetric while excited by normally incident plane wave or uniformly distributed normal force. And the smallest cell of finit element encircled by the symmetry plane is analyzed. The acoustic performance of double-layered plate with different types of coatings are numerically analyzed, such as uniform acoustic decoupling coating, hemispherical acoustic decoupling coating, conical cavity, cylindrical cavity and a variety of composite cavity. And the whole performance of coatings are dentally analyzed by changing the parameter of material, such as Young's modulus, loss factor of Young's modulus, density, thick, position of cavity, radius of cavity, and space of cavity.Some valuable conclusions are obtained through the numerical analysis on various coatings and can be very useful to theoretical design. The developed Acoustic simulation software has good adapabitity for various forms of cavity shape and various parameters of material of coatings.