Identiﬁcation of honeycomb sandwich properties by high-resolution modal analysis
M. Rebillat1,2a and X. Boutillon1
LMS-CNRS, École Polytechnique, 91128
2 LIMSI-CNRS, Universite Paris-Sud, B.P. 133, 91403 Orsay Cedex, France
a e-mail: firstname.lastname@example.org
Published online: 10 June 2010
A method is proposed to identify the mechanical properties of the skin and core materials of honeycomb sandwich. All the elastic coeﬃcients and loss-factors that matter in the dynamics of a panel in the thick-plate approximation are identiﬁed. To this end, experimental natural modes (i.e. eigenmodes of the damped system) are compared to the numerical modes of a large sandwich panel (lx,y/h ≃ 80). The chosen generic model for the visco-elastic behaviour of the materials is E (1 + jη). The numerical modes are computed by means of a Rayleigh-Ritz procedure and their dampings are predicted according to the visco-elastic model. The frequencies and dampings of the natural modes of the panel are estimated experimentally by means of a high-resolution modal analysis technique. An optimisation procedure yields the desired coeﬃcients. A sensitivity analysis assess the reliability of the method.
© Owned by the authors, published by EDP Sciences, 2010