A similitude for structural acoustic enclosures

A similitude is proposed for the analysis of the dynamic response of acousto-elastic assemblies. It is defined by invoking the energy distribution approach which allows the exact representation of all the fundamental parameters in terms of modal coordinates. The similitude laws are then defined by imposing that the dynamic responses in the original and parent models are the same. Herein, two test cases are discussed: the first is represented by the finite element modelling of a flexural plate coupled to an acoustic room; the second is purely analytical and concerns an infinite cylinder containing a fluid. If the original damping values are kept, it is shown that a complete similitude can be defined: it allows working with parent configurations of increased or reduced sizes. Even if the proposed schemes are very simple, the results are very promising.