Time domain FE-formulation for the equivalent fluid model

Publikation: Beitrag in Buch/Bericht/KonferenzbandBeitrag in einem Konferenzband


Acoustically absorbing materials such as acoustic foam can be described by the equivalent fluid model. The homogenized fluid’s acoustic behavior is thereby described by complex-valued, frequency-dependent material parameters (equivalent density and compression modulus).
In this case, convolution integrals of the material parameters and the acoustic pressure arise when the acoustic wave equation is transformed from frequency to time domain. We circumvent the direct calculation of these integrals by introducing auxiliary differential equations (ADEs), which are coupled to the wave equation according to the ADE method. The set of coupled differen-
tial equations is solved using the finite element method (FEM). The approach requires the equivalent fluid parameters to be modeled by a rational function representing the frequency-dependent material behavior (frequency response function, FRF). Thereby, the order of the FRF defines the number of additionally introduced ADEs and auxiliary variables. For the sake of simplicity,
the formulation’s derivation is presented for FRFs consisting of only one real pole. The passivity of the porous material is demonstrated, and it is validated against
a frequency-domain simluation in openCFS based on a two-dimensional duct containing an equivalent fluid.
TitelFortschriftte der Akustik - DAGA 2023
ISBN (elektronisch)978-3-939296-21-8
PublikationsstatusVeröffentlicht - 2023
VeranstaltungDAGA 2023 - 49. Jahrestagung für Akustik - Hamburg, Deutschland
Dauer: 6 März 20239 März 2023


KonferenzDAGA 2023 - 49. Jahrestagung für Akustik
KurztitelDAGA 2023


Untersuchen Sie die Forschungsthemen von „Time domain FE-formulation for the equivalent fluid model“. Zusammen bilden sie einen einzigartigen Fingerprint.

Dieses zitieren