Sound Insulation Properties Of Layered Damping Stiffened Panels Acoustic Shield

In practice of noise control in the industrial field, layered damping stiffened panels(LDSP) has been broadly used in the design of sound insulation. In the structure of LDSP, metal elastic layers provide mechanical intensity and elastic damping layers consume vibration energy. Because of little research in the field ,it is necessary to study the sound insulation of LDSP.This article carry on the study of LDSP. according to the equality of stress and displace which occur between the surface of damping panel's layer, I get the capacity of sound insulation based on transfer matrix method. Compared this result with another which got form the method based on the wave equation of basic acoustics. After that, I change the primary panel into stiffened one. On the assumption that stiffened panel is composed of rectangle plates which all boundaries are been fixed, I use flexibility theory of thin plate to educe the flexibility and stress of LDSP on the z direction. Add the result of flexibility and stress to the computation model and got the sound insulation loss. At last , making use of SEA method get the non-resonance coupling loss factor of sound. Then get the other SEA parameter calculate the capacity of sound insulation.Based on the solution about sound insulation capacity of LDSP, with transfer matrix method, the article put forward the assumption mat LDSP is composed of rectangle plate which all boundaries are been fixed. By theoretic analysis, give the difference between the general stiffened plate and LDSP, it is concluded that the constant of material mechanics of the middle layer plate also take a great influence on the effect of sound insulation. I get the non-resonance coupling loss factor between sound fields by SEA method. Then build up the model of airtight sound insulation cover based on LDSP, also give the capacity of sound insulation. This article gives a detailed analysis on the influence of the material mechanics constant of the middle layer plate to sound insulation capacity. It also gives a powerful reference to uncover the capacity of sound transmission and sound insulation of the LDSP.