A new type of muffler based on microperforated tubes

S Allam, M Åbom - 2011 - asmedigitalcollection.asme.org
Microperforated plate (MPP) absorbers are perforated plates with holes typically in the
submillimeter range and perforation ratios around 1%. The values are typical for …

Acoustic absorption modeling of single and multiple coiled-up resonators

A Magnani, C Marescotti, F Pompoli - Applied Acoustics, 2022 - Elsevier
This work proposes an improved design procedure of sound absorption metamaterials
consisting of acoustic coiled-up quarter-wave resonators that fit into a limited space, in order …

Prediction of ingestion through turbine rim seals—Part I: Rotationally induced ingress

JM Owen - 2011 - asmedigitalcollection.asme.org
The mainstream flow past the stationary nozzle guide vanes and rotating turbine blades in a
gas turbine creates an unsteady nonaxisymmetric variation in pressure in the annulus …

LattSAC: a software for the acoustic modelling of lattice sound absorbers

JW Chua, Z Lai, X Li, W Zhai - Virtual and Physical Prototyping, 2024 - Taylor & Francis
The increasingly distressing problem of noise pollution prompts the rapid research and
development of lattice-based acoustic materials for practical applications. These lattices …

Broadband and low-frequency sound absorption of modified Helmholtz resonator combined with porous layer addition

EF Vergara, GN Almeida, LR Barbosa… - Journal of Applied …, 2022 - pubs.aip.org
In this work, a hybrid acoustic material (HAM) is designed for broadband and low-frequency
sound absorption based on the combination of two different materials: a porous layer …

Optimisation of micro-perforated cylindrical silencers in linear and nonlinear regimes

T Bravo, C Maury, C Pinhède - Journal of Sound and Vibration, 2016 - Elsevier
This paper describes analytical and experimental studies conducted to understand the
potential of lightweight non-fibrous alternatives to dissipative mufflers for in-duct noise …

Transfer impedance of microperforated materials with tapered holes

T Herdtle, J Stuart Bolton, NN Kim… - The Journal of the …, 2013 - pubs.aip.org
It has been previously shown that relatively simple computational fluid dynamics (CFD)
models can be used to calculate the transfer impedances, including the associated end …

Hybrid noise control in a duct using a light micro-perforated plate

XN Wang, YS Choy, L Cheng - The Journal of the Acoustical Society of …, 2012 - pubs.aip.org
A plate silencer consists of an expansion chamber with two side-branch cavities covered by
light but extremely stiff plates. It works effectively with a wide stopband from low-to-medium …

Strouhal number dependency of the aero-acoustic response of wall perforations under combined grazing-bias flow

EMT Moers, D Tonon, A Hirschberg - Journal of Sound and Vibration, 2017 - Elsevier
The influence of low Mach number grazing-bias flow on the linear acoustic response of slit
shaped wall perforations is determined in terms of a dimensionless acoustical impedance …

The Effect of deviation due to the manufacturing accuracy in the parameters of an MPP on its acoustic properties: Trial production of MPPs of different hole shapes …

K Sakagami, M Kusaka, T Okuzono, S Nakanishi - Acoustics, 2020 - mdpi.com
In this study, we discuss the effect of the manufacturing accuracy of a microperforated panel
(MPP) produced by 3D printers on acoustic properties through measured and calculated …