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Numerical Algorithms for Acoustic Integrals - The Devil is in the DetailsThe accurate prediction of the aeroacoustic field generated by aerospace vehicles or nonaerospace machinery is necessary for designers to control and reduce source noise. Powerful computational aeroacoustic methods, based on various acoustic analogies (primarily the Lighthill acoustic analogy) and Kirchhoff methods, have been developed for prediction of noise from complicated sources, such as rotating blades. Both methods ultimately predict the noise through a numerical evaluation of an integral formulation. In this paper, we consider three generic acoustic formulations and several numerical algorithms that have been used to compute the solutions to these formulations. Algorithms for retarded-time formulations are the most efficient and robust, but they are difficult to implement for supersonic-source motion. Collapsing-sphere and emission-surface formulations are good alternatives when supersonic-source motion is present, but the numerical implementations of these formulations are more computationally demanding. New algorithms - which utilize solution adaptation to provide a specified error level - are needed.
Document ID
19960024787
Document Type
Conference Paper
Authors
Brentner, Kenneth S. (NASA Langley Research Center Hampton, VA United States)
Date Acquired
August 17, 2013
Publication Date
May 8, 1996
Subject Category
Acoustics
Report/Patent Number
AIAA Paper 96-1706
NAS 1.15:111588
NASA-TM-111588
Meeting Information
AIAA/CEAS Aeroacoustics Conference(State College, PA)
Distribution Limits
Public
Copyright
Public Use Permitted.
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