Acoustic properties of model cellular vitreous carbon foams

This paper deals with the relations between structural and acoustic properties of model vitreous carbon foams, i.e., presenting different porous structures in terms of bulk density, cell size and connectivity, while having the same composition and the same carbon texture. This is a major achievement with respect to former studies, in which foams had cell sizes directly correlated to their total porosity, thus preventing the independent analysis of these two parameters. The permeability k0 and the absorption coefficients A of these new carbon foams were studied in relation to their porous structures. k0 was controlled by cell diameter, and an absorption optimum is expected in the range 1×10−9m²

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