 |
Composite materials are widely used in the aerospace industry, for their low mass and high stiffness, however, these characteristics tend to increase noise transmission. Sound protection must therefore be added, in the form of porous material layers. Uncertainties may affect both the structural and sound package parameters. It is therefore important to assess the influence of these uncertain parameters on the sound transmission properties of the assembly. The sound transmission loss through a composite plate-foam assembly is first computed with the transfer matrix method. The effect of uncertainty of several parameters such as the porosity, flow resistivity and mechanical parameters is then analysed with the FAST (Fourier amplitude sensitivity test) method. The effect of adding a thin screen at the interface between the porous and the air is also investigated.
