An experimental validation of a nonlinear acoustic resistance model for an acoustically compact area contraction with steady mean flow

Abstract A method for controlling noise level in duct flows is described. The method is based on the principle of energy extraction by active source(s), rather than by wave cancellation as in “anti-sound”. As such the method of energy extraction is robust; it does not need the delicate signal processing, perfect phase and amplitude matching, crucial to sound cancellation. Analysis indicates that in the presence of through flow the control is effective in extracting energy from any waves traversing it. As the duct flow Mach number increases the control appears to be less effective for waves produced upstream of it but it is more effective for the waves produced downstream of the device. Further, this conclusion remains valid whether the detector is placed on the upstream or downstream side of the control device. A future paper will report the experimental validation of the analysis.

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ON NONLINEAR ACOUSTIC RESISTANCE OF A PERFORATED PLATE

Acta Physica Sinica ◽

10.7498/aps.27.600 ◽

1978 ◽

Vol 27 (5) ◽

pp. 600

Author(s):

ZHAO SONG-LING ◽

LU YUAN-WEI

Keyword(s):

Perforated Plate ◽

Acoustic Resistance ◽

Nonlinear Acoustic

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An Experimental Study of the Nonlinear Acoustic Response of Sense-lines with Steady Mean Flow

2018 AIAA Aerospace Sciences Meeting ◽

10.2514/6.2018-1002 ◽

2018 ◽

Author(s):

Thomas W. Teasley ◽

David E. Scarborough

Keyword(s):

Experimental Study ◽

Acoustic Response ◽

Mean Flow ◽

Nonlinear Acoustic

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Experimental Validation of an Analytical Prediction Model for Fan Buzz-Saw Noise

Volume 2D: Turbomachinery ◽

10.1115/gt2020-14279 ◽

2020 ◽

Author(s):

Antoine Moreau ◽

Sébastien Guérin

Keyword(s):

Mach Number ◽

Prediction Model ◽

Analytical Model ◽

Experimental Validation ◽

Test Cases ◽

Sound Power ◽

Analytical Prediction ◽

Mean Flow ◽

Reasonable Prediction ◽

Inflow Conditions

Abstract This paper is focused on the application of an analytical model, which was previously developed and published for the prediction of buzz-saw noise emitted by supersonic fan rotors. The application test cases are six different fan stages equipped with hardwall inlet ducts and clean inflow conditions. The model is validated through a comparison with experimental sound power levels measured along the working line of each fan in high subsonic, transonic and supersonic regimes. In terms of overall evolution and maximum levels, the model provides a reasonable prediction; the sensitivity to parameters such as the intake axial Mach number or the intake duct length is well reproduced. However the significant discrepancies observed locally show that the prediction of buzz-saw noise is still a difficult task. The model is then extended to the case of distorted mean flow impinging on the rotor. Following this extension, the maximum levels of buzz-saw noise are expected to occur over a wider range of Mach number compared to the case with clean inflow.

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Low-dispersion scheme for nonlinear acoustic waves in nonuniform mean flow

10.2514/6.1997-1582 ◽

1997 ◽

Author(s):

Oktay Baysal ◽

Dinesh Kaushik ◽

Moumen Idres ◽

Oktay Baysal ◽

Dinesh Kaushik ◽

...

Keyword(s):

Acoustic Waves ◽

Mean Flow ◽

Nonlinear Acoustic ◽

Low Dispersion

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Experimental Validation of a 2-D Constriction Resistance Model at the Microscale

10.1109/holm.2009.5284387 ◽

2009 ◽

Author(s):

Lise Bilhaut ◽

Christophe Poulain ◽

Romain Anciant ◽

Laurent Duraffourg

Keyword(s):

Experimental Validation ◽

Constriction Resistance ◽

Resistance Model

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Generation of vorticity motion by sound in a chemically reacting gas and inversion of acoustic streaming in the non-equilibrium regime

Open Physics ◽

10.2478/s11534-010-0077-x ◽

2011 ◽

Vol 9 (3) ◽

Cited By ~ 2

Author(s):

Anna Perelomova ◽

Paweł Wojda

Keyword(s):

Acoustic Streaming ◽

Mean Flow ◽

Acoustic Source ◽

The Mean ◽

Nonlinear Acoustic ◽

Chemically Reacting ◽

And Inversion ◽

Equilibrium Chemical ◽

Stimulation Of ◽

Non Equilibrium

AbstractNonlinear stimulation of the vorticity mode caused by losses in the momentum of sound in a chemically reacting gas is considered. The instantaneous dynamic equation for the vorticity mode is derived. It includes a quadratic nonlinear acoustic source, which reflects the fact that the reason for the interaction between sound and the vorticity mode is nonlinear. Both periodic and aperiodic sound may be considered as the origin of the vorticity flow. The equation governing the mean flow (the acoustic streaming) in the field of periodic sound is also derived. In the non-equilibrium regime of a chemical reaction, there may exist streaming vortices whose direction of rotation is opposite to that of the vortices in the standard thermoviscous flows. For periodic sound, this is illustrated by an example. The theory and the example describe both equilibrium and non-equilibrium chemical reactions.

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