Table of Contents

Lattice Boltzmann Modeling of Acoustic Systems

Participants: Shi Yong, Andrey da Silva and Gary Scavone

Period: 2005 - ongoing


The mechanisms of sound production in single-reed woodwind instruments are not yet fully understood. Rather than being simply explained by the coupling between the reed and the acoustic field within the bore, the characteristics of the sound seem to be strongly influenced by phenomena associated with the presence of the airflow driven by the player into the instrument.

The flow-induced excitation of the reed appears to be a major occurrence among the list of flow-related phenomena. Unlike the case of the larynx in the human phonatory system, the flow-induced oscillation of the reed is not a predominant factor on the process of self-sustained oscillation but plays an important role in the characteristics of sound. Furthermore, the unsteadiness of the downstream flow in normal playing conditions is another flow-related phenomenon, which acts as a major factor on the nonlinear dissipation of the acoustic energy within the instrument's bore and on the instrument's radiation directivity.

The goal of this research is to conduct numerical studies of the above-mentioned phenomena in order to provide a deeper understanding of the mechanisms responsible for the sound quality of woodwind instruments. These numerical models are constructed by using the lattice Boltzmann method, which has the advantage of providing integrated solutions for the different scales associated with the acoustic field and the flow, thus allowing the representation of the fluid-acoustic interaction.