Acoustic end correction in micro-perforated plates - Revisited
2014 (English)In: 21st International Congress on Sound and Vibration 2014, ICSV 2014, 2014, 1203-1209 p.Conference paper (Refereed)
Micro-Perforated plates (MPP) are plates with a porosity of the order of 1% in which the perforation diameter is optimized for absorption of incident acoustic waves. The concept has been introduced by Maa, who proposed an analytical model based on the solution for the oscillating viscous flow in a long capillary tube. The finite length of the geometry is taken into account by reactive and resistive end-corrections of Ingard. In order to match experimental data, the single sided resistive end correction of Ingard has been multiplied by a factor a. This factor varies in the literature in the range 2 ≤ α ≤ 4. Bolton and Kim propose the use of CFD to determine these end-corrections. Using a similar approach, our present work proposes an alternative result to their work. We use a linear numerical model based on incompressible Navier-Stokes equations in 2D-axisymmetric coordinates, which is solved in the Fourier domain, rather than the time domain simulation as proposed by Bolton and Kim. Working in the Fourier domain with linearized equations ensures the numerical efficiency and absence of non-linear effects. We furthermore use an alternative procedure to determine the inertial part of the transfer impedance leading to a difference of the order of 10% with the results of Bolton and Kim. Moreover, our results show that resistive and reactive end corrections are mainly a function of the Shear number Sh. The porosity a and plate thickness to perforation diameter ratio t∗ seems to be less important.
Place, publisher, year, edition, pages
2014. 1203-1209 p.
Acoustic impedance, Acoustics, Computational fluid dynamics, Oscillating flow, Perforated plates, Porosity, Porous plates, Time domain analysis, Viscous flow, Alternative procedures, End corrections, Incompressible Navier Stokes equations, Linearized equations, Nonlinear effect, Numerical efficiency, Time-domain simulations, Transfer impedance, Navier Stokes equations
IdentifiersURN: urn:nbn:se:kth:diva-167940ScopusID: 2-s2.0-84922591209ISBN: 9781634392389OAI: oai:DiVA.org:kth-167940DiVA: diva2:817428
21st International Congress on Sound and Vibration 2014, ICSV 2014, 13 July 2014 through 17 July 2014
QC 201506052015-06-052015-05-222016-09-16Bibliographically approved