Acoustic characterization of a hybrid liner consisting of porous material by using a unified linearized navier-stokes approach
2016 (English)In: 22nd AIAA/CEAS Aeroacoustics Conference, 2016, American Institute of Aeronautics and Astronautics, 2016Conference paper (Refereed)
In this paper, the acoustic properties of a hybrid liner placed at the end of an impedance tube are investigated using numerical simulations. The hybrid liner constitutes of three components, a perforated plate, a porous layer and a rectangular back cavity. The presence of the porous layer is to enhance the absorptive performance of a liner. The main objective of the paper is to verify the proposed numerical methodology - a unified linearized Navier-Stokes Equations (LNSE) approach. In the unified LNSE approach, the combination of the Helmholtz Equation, LNSE as well as the equivalent fluid model are solved in different regions of the impedance tube. To achieve this, the continuity of the coupling condition between the LNSE and the Helmholtz equation is examined. Another objective is to analyze the effectiveness of the porous material to the acoustic performance of the liner. Acoustic liner simulations with and without porous material, porous material with different flow resistivity are carried out. A good agreement is found between the numerical results and the measurements previously performed at KTH MWL.1 Compared to previous work234, several improvements have been made in the numerical methodology, such as that the energy equation has been added in order to include the damping due to viscous dissipation as well as the thermal dissipation in the vicinity of the perforated plate.
Place, publisher, year, edition, pages
American Institute of Aeronautics and Astronautics, 2016.
Acoustic impedance, Acoustic properties, Aeroacoustics, Characterization, Helmholtz equation, Linearization, Numerical methods, Oil well casings, Perforated plates, Porous materials, Viscous flow, Acoustic characterization, Acoustic performance, Coupling condition, Linearized Navier-Stokes, Linearized navier-stokes equations, Numerical methodologies, Thermal dissipation, Viscous dissipation, Navier Stokes equations
IdentifiersURN: urn:nbn:se:kth:diva-194621ScopusID: 2-s2.0-84982871151ISBN: 9781624103865OAI: oai:DiVA.org:kth-194621DiVA: diva2:1043829
22nd AIAA/CEAS Aeroacoustics Conference, 2016, 30 May 2016 through 1 June 2016
Conference Paper. QC 201611012016-11-012016-10-312016-11-01Bibliographically approved