M. De Gennaro, H. Kühnelt:

"Wiener-Hopf Technique for Acoustic Characterization of Duct Elements";

Vortrag: Forum Acusticum 2011, Aalborg, Dänemark; 27.06.2011 - 01.07.2011; in: "Proceedings of Forum Acusticum 2011", Danish Acoustical Society, 411 (2011), ISBN: 978-84-694-1520-7; S. 1 - 6.

The Wiener-Hopf (W-H) technique is a methodology used for the system identification developed in the frame of communications engineering. It is based on the assumption that a generic system can be identified by a transfer matrix able to correlate system inputs to system outputs via a set of coefficients that are determined by the system itself. This assumption can be considered valid also in

the case of duct elements for HVAC applications that are acoustically characterized by a two-port transfer matrix correlating upstream and downstream acoustic pressure and velocity. According to

the W-H technique a generic system can be identified by its time-dependent responses to a series of input impulses. Knowing the time-histories of input and output signals it is possible to reconstruct

the transfer matrix coefficients with an algebraic procedure.

The target of this paper is to provide a detailed description of this methodology coupled with Computational Fluid Dynamics (CFD) for the characterization of the acoustic transfer matrix for a

duct element. Time series of acoustic pressure and velocity are calculated by time-dependant RANS simulation for an area change duct geometry and results are compared with an analytical solution

available in literature. Moreover particular attention is given to CFD simulation requirements, boundary conditions, computational grid and solver settings in order to estimate the acoustic transfer

matrix of HVAC components with highly competitive computational cost.

Erstellt aus der Publikationsdatenbank des AIT Austrian Institute of Technology.