Passive models of viscothermal wave propagation in acoustic tubes.
A continued fraction expansion to the immittances defining viscothermal wave propagation in a cylindrical tube has been presented recently in this journal, intended as a starting point for time domain numerical method design. Though the approximation has the great benefit of passivity, or positive realness under truncation, its convergence is slow leading to approximations of high order in practice. Other passive structures, when combined with optimisation methods, can lead to good accuracy over a wide frequency range, and for relatively low order.
Acoustics and Audio Group, University of Edinburgh, Kings Buildings, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom.
Stefan
S
Bilbao
Acoustics and Audio Group, University of Edinburgh, Kings Buildings, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom.
Reginald
R
Harrison
Laboratoire de Mécanique et Acoustique, CNRS-UPR 7051, Université Aix-Marseille, Centrale Marseille, 13402 Marseille Cedex 20, France.
Jean
J
Kergomard
Laboratoire de Mécanique et Acoustique, CNRS-UPR 7051, Université Aix-Marseille, Centrale Marseille, 13402 Marseille Cedex 20, France.
Bruno
B
Lombard
Laboratoire de Mécanique et Acoustique, CNRS-UPR 7051, Université Aix-Marseille, Centrale Marseille, 13402 Marseille Cedex 20, France.
Christophe
C
Vergez