A substructuring technique for finite element wave propagation in multi-layered systems

In this paper, the guided wave propagation in multi-layered elastic slender systems is numerically analyzed. In this context, the applicability of the wave finite element (WFE) formulation is discussed for the description of the wave modes and their frequency evolutions. The WFE formulation suffers from a number of numerical issues, especially when multi-layered structures are concerned. To address this problem, a dynamic substructuring technique is proposed, which allows the dynamics of a typical layer cross-section to be projected on a reduced local wave mode basis with appropriate dimension. The formulation, termed modified wave finite element (MWFE), allows the standard wave motions of multi-layered systems to be correctly captured. Numerical simulations and comparisons with classic theories show the pertinence of the modelings.