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Sandwich structures are widely used in several sectors, including aerospace and other branches of civil and mechanical engineering, thanks to their lightweight properties together with a high bending stiffness. This trend is imposed by demands for high load capacity and reduced consumption. From an acoustic point of view, decreasing the mass could have a significant influence on the vibro-acoustic performance of the structure. As a result, it might lead to unsatisfactory noise reduction properties. Therefore, a meso-macro approach is developed to control the acoustic properties. The approach connects the meso-scale parameters of the honeycomb sandwich panel to their macro-scale vibro-acoustic properties.
The prediction of accurate wave dispersion characteristics in a cellular honeycomb core bonded by two laminated orthotropic face-sheets is key information for computing the vibro-acoustic indicators. In the last decade, various analytical methods have been developed to predict the wave dispersion characteristics taking into account deflections due to the shear of the core in the sandwich panel. However, the analytical methods do not reveal the meso-scale influence on the acoustic transmission of the sandwich structure.
The present work aims to bring out the effects of the different meso-scale parameters of the honeycomb sandwich panel on their vibro-acoustic response using a meso-macro approach. The present approach is developed using a numerical method known as wave finite element method (WFEM). The WFE method combines the classical finite element method (FEM) and the periodic structure theory (PST). The main advantage of this method is that it takes into consideration the periodicity of the structure, which allows to model typically just one elementary cell instead of the whole structure. Accordingly, the calculations cost is hugely reduced. In addition to that, this numerical model keeps the meso-scale parameters of the periodic cell. The obtained results are compared with different analytical methods and commercial tool (Ms-NOVA), showing a very good agreement.
