Finite Element Prediction of Damping in Structures with Constrained Viscoelastic Layers

TLDR

The study presents an efficient finite element method for modelling three‑layer laminates with a viscoelastic layer and discusses its application to designing integrally damped structures. The method estimates modal damping ratios using the modal strain energy approach and compares NASTRAN MSE results with exact solutions and experimental data. The method yields frequencies, modal damping ratios, and mechanical admittances for simple beams, plates, and rings.

Abstract

An efficient method is described for finite element modelling of three-layer laminates containing a viscoelastic layer. Modal damping ratios are estimated from undamped normal mode results by means of the modal strain energy method. Comparisons are given between results obtained by the MSE method implemented in NASTRAN, by various exact solutions for approximate governing differential equations, and by experiment. Results are in terms of frequencies, modal damping ratios, and mechanical admittances for simple beams, plates, and rings. Application of the finite element -- MSE method in design of integrally damped structures is discussed.