Wave field of acoustic antenna in uniform subsonic flow
Bryukhovetski, AS, Vichkan’, AV |
Organization:
O. Ya. Usikov Institute for Radiophysics and Electronics of the National Academy of Sciences of Ukraine |
https://doi.org/10.15407/rej2019.03.009 |
Language: russian |
Abstract:
Subject and purpose. The wave field of an acoustic antenna in a uniform subsonic flow is theoretically investigated. Purpose of the work is to obtain an analytical dependence of the sound field on physical parameters. Method and methodology. The article presents the aperture method of theoretical calculation of wave field of the acoustic antenna, which on the approximate Kirchhoff boundary conditions and the Fourier method of separation of variables in the wave equation for a moving medium. In determining the coordinate representation of the sound field in the wave zone of the source from its frequency-wave representation, is used the asymptotic method of the stationary phase for calculating double oscillating integrals. Results. It is established that the wave field of an acoustic antenna is represented as a product of the wave field of a point source and a spatial angular factor, which depend not only on the position of the observation point, but also on the flow velocity vector. Conclusion. It was shown that the results of calculations can serve as a theoretical basis for explaining the experimental data for radio acoustic sounding of the atmosphere. |
Keywords: anisotropy, aperture method, Kirchhoff diffraction, saddle point method |
Manuscript submitted 29.11.2018
PACS 94.20.ws, 43.20.Bi
Radiofiz. elektron. 2019, 24(3): 9-20
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