The partition of unity finite element method for short wave acoustic propagation on non-uniform potential flows
The partition of unity finite element method for short wave acoustic propagation on non-uniform potential flows
A novel numerical method is proposed for modelling time-harmonic acoustic propagation of short wavelength disturbances on non-uniform potential flows. The method is based on the partition of unity finite element method in which a local basis of discrete plane waves is used to enrich the conventional finite element approximation space. The basis functions are local solutions of the governing equations. They are able to represent accurately the highly oscillatory behaviour of the solution within each element while taking into account the convective effect of the flow and the spatial variation in local sound speed when the flow is non-uniform. Many wavelengths can be included within a single element leading to ultra-sparse meshes.
Results presented in this article will demonstrate that accurate solutions can be obtained in this way for a greatly reduced number of degrees of freedom when compared to conventional element or grid-based schemes. Numerical results for lined uniform two-dimensional ducts and for non-uniform axisymmetric ducts are presented to indicate the accuracy and performance which can be achieved. Numerical studies indicate that the pollution effect associated with cumulative dispersion error in conventional finite element schemes is largely eliminated.
potential flow acoustics, partition of unity method, short wave problems
425-444
Gamallo, P.
cb7fed9f-a96a-4b58-8939-6db1010f9893
15 January 2006
Gamallo, P.
cb7fed9f-a96a-4b58-8939-6db1010f9893
Gamallo, P.
(2006)
The partition of unity finite element method for short wave acoustic propagation on non-uniform potential flows.
International Journal for Numerical Methods in Engineering, 65 (3), .
(doi:10.1002/nme.1459).
Abstract
A novel numerical method is proposed for modelling time-harmonic acoustic propagation of short wavelength disturbances on non-uniform potential flows. The method is based on the partition of unity finite element method in which a local basis of discrete plane waves is used to enrich the conventional finite element approximation space. The basis functions are local solutions of the governing equations. They are able to represent accurately the highly oscillatory behaviour of the solution within each element while taking into account the convective effect of the flow and the spatial variation in local sound speed when the flow is non-uniform. Many wavelengths can be included within a single element leading to ultra-sparse meshes.
Results presented in this article will demonstrate that accurate solutions can be obtained in this way for a greatly reduced number of degrees of freedom when compared to conventional element or grid-based schemes. Numerical results for lined uniform two-dimensional ducts and for non-uniform axisymmetric ducts are presented to indicate the accuracy and performance which can be achieved. Numerical studies indicate that the pollution effect associated with cumulative dispersion error in conventional finite element schemes is largely eliminated.
This record has no associated files available for download.
More information
Published date: 15 January 2006
Keywords:
potential flow acoustics, partition of unity method, short wave problems
Identifiers
Local EPrints ID: 27992
URI: http://eprints.soton.ac.uk/id/eprint/27992
ISSN: 0029-5981
PURE UUID: 9792c104-b015-439d-98c8-611c5f94fb6c
Catalogue record
Date deposited: 28 Apr 2006
Last modified: 15 Mar 2024 07:22
Export record
Altmetrics
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics