Non-linear model reduction method applied to viscoelastically damped sandwich structures

The aim of this paper is to present an efficient non-linear model reduction method intended to temporal dynamic analysis of viscoelastic sandwich structures. The proposed non-linear model reduction method is based on the combination of modal synthesis method, as well known, substructuring technique and Guyan reduction method. Each substructure is analyzed and reduced separately as a linear finite element model. The viscoelastic behavior of the core, which depends on frequency, is represented by Golla-Hughes-Mc Tavish (GHM) model. This model allows a correct representation of viscoelastic materials characteristics through the addition of dissipative coordinates. Once obtained, the reduced models of each substructure are assembled taking into account the local nonlinearities in the junctions leading to perform the capacity of the proposed method to reproduce the original model with accuracy and (CPU) time gain. Numerical examples are presented to illustrate the ability of the proposed non-linear model reduction method to handle both viscoelasticity and large finite elements models.