Time-domain damping models in structural acoustics using digital filtering

Augustin Parret-Fréaud (1) , Benjamin Cotté (2) , Antoine Chaigne (1)

1 DFA - Dynamique des Fluides et Acoustique
2 IMSIA - UMR 9219 - Institut des Sciences de la mécanique et Applications industrielles

This paper describes a new approach in order to formulate well-posed time-domain damping models able to represent various frequency domain profiles of damping properties. The novelty of this approach is to represent the behavior law of a given material directly in a discrete-time framework as a digital filter, which is synthesized for each material from a discrete set of frequency-domain data such as complex modulus through an optimization process. A key point is the addition of specific constraints to this process in order to guarantee stability, causality and verification of thermodynamics second law when transposing the resulting discrete-time behavior law into the time domain. Thus, this method offers a framework which is particularly suitable for time-domain simulations in structural dynamics and acoustics for a wide range of materials (polymers, wood, foam, etc.), allowing to control and even reduce the distortion effects induced by time-discretization schemes on the frequency response of continuous-time behavior laws.

Mots clés: Digital filtering; Damping; Time-domain modeling; Vibroacoustics

Domaines: Mécanique [physics]; Acoustique [physics.class-ph]

Augustin Parret-Fréaud, Benjamin Cotté, Antoine Chaigne. Time-domain damping models in structural acoustics using digital filtering. Mechanical Systems and Signal Processing, 2016, 68-69, pp.587-607. ⟨10.1016/j.ymssp.2015.08.005⟩. ⟨hal-01253180⟩