Finite Element Modeling and Design of Honeycomb Sandwich Panels for Acoustic Performance

Honeycomb cellular metamaterial structures offer many distinct advantages over homogenous materials because their effective material properties depend on both their constituent material properties and their geometric cell configuration. From this, a wide range of targeted effective material properties can be achieved thus supporting forward design by tailoring the honeycomb cellular materials and properties for specific applications. One area that has not been fully explored is the set of acoustic properties of honeycomb materials and how these can offer increased design flexibility when targeting acoustic performance. Understanding these relations, the designer can effectively tune designs to perform better in specific acoustic applications. One such example is the insulation of target sound frequencies to prevent sound transmission through a panel. This work explores how certain geometric and effective structural properties of in-plane honeycomb cores in sandwich panels affect the sound transmission loss properties of the panel. The two acoustic responses of interest in this work are the general level of sound transmission loss of the panel and the location of the frequencies related to the natural frequencies that exhibit high levels of sound transmission, or low sound transmission loss. Two different studies comparing constant mass sandwich panels and constant core shear modulus sandwich panels are conducted to determine the effects of varying properties. The results of these studies are used to formalize a design method, which is then used on a test case design application