STUDY OF SCATTERING, PRODUCTION, AND STIMULATED EMISSION OF SOUND BY VORTEX FLOWS
The basic theory of aeroacoustics, using the Bernoulli enthalpy concept, is applied to the problems of sound scattering, production, and stimulated emission. A general theory of scattering from low speed three-dimensional vortex flows is presented. Specific results are given for the horseshoe vortex and vortex ring. The noise of an elementary corotating vortex pair in various flows is calculated. It is shown that a potential flow and shear flow can substantially increase the basic pair noise. The results for six vortices illustrate how external pure tones can amplify the broadband noise of a jet.
National Aeronautics and Space Administration600 Independence Avenue, SW
Washington, DC United States 20546
- Yates, J E
- Publication Date: 1979-5
- Features: References;
- Pagination: 61 p.
- TRT Terms: Acoustic properties; Aerodynamic noise; Aerodynamics; Aircraft; Aircraft noise; Flow; Jet engines; Noise; Pollutants; Production; Simulation; Vortices
- Uncontrolled Terms: Scatter
- Old TRIS Terms: Acoustic effects; Aeroacoustics; Jet engine noise; Jet noise
- Subject Areas: Aviation; Environment; Vehicles and Equipment;
- Accession Number: 00301383
- Record Type: Publication
- Source Agency: Engineering Index
- Report/Paper Numbers: CR-3139 Contr Rpt.
- Files: TRIS
- Created Date: Feb 11 1980 12:00AM