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Output of acoustical sourcesAcoustic radiation from a source, here viewed as an immobile point singularity with periodic strength and a given multipolar nature, is affected by the presence of nearly structural elements (e.g., rigid or impedance surfaces) as well as that of a background flow in the medium. An alternative to the conventional manner of calculating the net source output by integrating the energy flux over a distant control surface is described; this involves a direct evaluation of the secondary wavefunction at the position of the primary source and obviates the need for a (prospectively difficult) flux integration. Various full and half-planar surface configurations with an adjacent source are analyzed in detail, and the explicit results obtained, in particular, for the power factor of a dipole brings out a substantial rise in its output as the source nears the sharp edge of a half-plane.
Document ID
19800053636
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Levine, H.
(Stanford University Stanford, Calif., United States)
Date Acquired
August 10, 2013
Publication Date
June 1, 1980
Publication Information
Publication: Acoustical Society of America
Subject Category
Acoustics
Accession Number
80A37806
Funding Number(s)
CONTRACT_GRANT: NSG-2215
Distribution Limits
Public
Copyright
Other

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