Estimation of rms strain in laminated face plates of simply-supported sandwich panels subjected to random acoustic loading. Including a simplified natural frequency prediction method
ESDU 86024 introduces a Fortran program@ available on disc (uncompiled) in the software volume as ESDUpac A8624@ to calculate the rms surface strains in two orthogonal directions at the centre of the face plates. In estimating strains it is assumed the panel responds only in its fundamental mode and that the loading spectral density is constant over a range of frequencies that includes the predominant response frequency. The method applies to sandwich panels with thin@ flat or slightly curved@ face plates having principal axes of orthotropy parallel to the panel edges; the face plates may be of dissimilar materials and thicknesses@ and the core is assumed to have simply-supported edges but@ since that cannot be achieved in practice@ the use of effective panel dimensions allows real edge conditions to be approximated and guidance is included on the choice of values. A comparison is shown of experimental results@ for centre strains extracted from the literature for honeycomb core sandwich panels with fibre-reinforced laminated face plates@ and rms strains predicted using the program.