A wave approach to estimating frequency-dependent damping under transient loading

A wave model is proposed for estimating damping loss factor as a function of frequency for a beam with arbitrary transient loading applied through the boundary conditions. In contrast to modal methods which provide measures of damping only at the modal frequencies of the test structure, the damping factor is determined over discrete, but regularly spaced, frequency values associated with the temporal sampling frequency. This makes it possible to predict or simulate damping in complex structures built from the tested component. Numerical and experimental data from a free-free beam are used to validate the approach. (C) 2000 Academic Press.