This paper describes the development and application of a time-domain acous
tic liner model which is suitable for the simulation of sound propagation a
nd attenuation in lined ducts. The fluid Row within the duct domain is repr
esented by the non-linear. unsteady Euler equations while the liner model c
onsists of a resistive frequency-independent part and a reactive part which
is obtained by solving the one-dimensional Euler equations within the line
r cavity. Specialized boundary conditions are used for matching the 1D cavi
ty Row and the 2D duct flow. The liner model has been formulated in order t
o predict the sound attenuation with or without mean Row. as well as for li
near or non-linear sound propagation. The model has been validated in the c
ase of linear pure-tone and N-wave signals by checking against analytical F
ormulations obtained via eigensolutions of the linearized inviscid Row equa
tions. Very good agreement was obtained for both zero and subsonic mean flo
ws. (C) 2001 Academic Press.