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Comparison of FFP predictions with measurements of a low-frequency signal propagated in the atmosphereAn experimental study of low-frequency propagation over a distance of 770 m was previously reported (J. Acoust. Soc. Am. Suppl. 1 86, S120 (1989)). For that study, sound speed profiles were reconstructed entirely from surface-layer micrometeorological data. When the acoustic data were compared with theoretical predictions from a fast field program (FFP), it was found that the FFP underpredicted sound levels measured in a shadow zone. Here, the effect on the predictions of including meteorological data for heights greater than the surface layer, i.e., wind profiles measured by a Doppler sodar, is discussed. Vertical structure of turbulence is simulated by stochastically perturbing the mean profiles, and the agreement between the acoustic data and FFP predictions is improved.
Document ID
19910007385
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Wilson, K. Keith
(Pennsylvania State Univ. University Park, PA, United States)
Thomson, Dennis W.
(Pennsylvania State Univ. University Park, PA, United States)
Date Acquired
September 6, 2013
Publication Date
December 1, 1990
Publication Information
Publication: NASA, Langley Research Center, 4th International Symposium on Long-Range Sound Propagation
Subject Category
Acoustics
Accession Number
91N16698
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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