Jet Noise : 1st Report, Far Noise Field of Subsonic Free Air Jet
نویسندگان
چکیده
منابع مشابه
Nonlinear interaction model of subsonic jet noise.
Noise generation in a subsonic round jet is studied by a simplified model, in which nonlinear interactions of spatially evolving instability modes lead to the radiation of sound. The spatial mode evolution is computed using linear parabolized stability equations. Nonlinear interactions are found on a mode-by-mode basis and the sound radiation characteristics are determined by solution of the Li...
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A subsonic circular jet with a Mach number of 0.9 and a Reynolds number of 65 000 is computed by a compressible Large Eddy Simulation (LES) to determine both the flow field and the sound field in the same calculation. The noise radiated by the jet, provided by LES, is in good agreement with experimental data of the literature in terms of sound pressure spectra, levels and directivity, showing t...
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Jets are one of the most fascinating topics in fluid mechanics. For aeronautics, turbulent jet-noise modelling is particularly challenging, not only because of the poor understanding of high Reynolds number turbulence, but also because of the extremely low acoustic efficiency of high-speed jets. Turbulent jet-noise models starting from the classical Lighthill acoustic analogy to state-of-the ar...
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This study is motivated by the development of aircraft that use jet noise shielding by the airframe. Current methods to predict shielding from aircraft surfaces rely on formulae developed for diffraction of sound from omnidirectional point sources. However, the jet noise source is distributed and directional, thus requiring a different approach. In this study, the jet noise source is modeled as...
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ژورنال
عنوان ژورنال: Transactions of the Japan Society of Mechanical Engineers
سال: 1963
ISSN: 0029-0270,2185-9485
DOI: 10.1299/kikai1938.29.969