Acoustic field associated with parabolized stability

Jet noise and its reduction is a technological problem of great importance that has received continuous understanding of the physics involved in the generation of turbulent mixing noise and reduced-order models for its prediction and control are lacking. the study of forced supersonic jets,2,15,17,18 for which the measured near-field

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Alternating lobed mixer/ejector concept suppressor - Stage

A mixer/ejector suppressor is disclosed for reducing the noise level created by the exhaust flows in gas turbines. In the preferred embodiment, the suppressor comprises a mixing ring of alternating lobes attached to the engine's tailpipe; an ejector shroud mounted onto the mixing ring; and a plurality of arcuate gaps, between the mixing ring and ejector shroud, that permit ambient air to be

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Two-stage mixer ejector suppressor - Stage III

Thrust is obtained through larger mass flow rates, and lower jet velocities. This results in much lower jet noise levels. Accordingly, it is a primary object of the present invention to provide a multi-stage mixer ejector system that decreases the noise levels of older engines, within short shrouds, to meet the new Stage III noise regulations.

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Noise radiated by a non-isothermal, temporal mixing layer

Vol. IV: Theory of turbulence generated jet noise, noise radiation from upstream sources and combustion noise. Part II: Generation of sound in a mixing region. U.S. Air Force Aero Propulsion Lab., AFAPL-TR-72-53 (1972) 31. Lilley, G.M.: The radiated noise from isotropic turbulence with applications to the theory of jet noise. J. Sound Vib.

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A Collection of Technical Papers 9th AIAA/CEAS

Predicting Forced Mixer Jet Noise L. Garrison, A. Lyrintzis, G. Blaisdell, and W. Dalton 571 Large Eddy Simulation of Plane Jet Sound Radiation Z. Hu, C. Morfey, and N. Sandham 581 Multiple-Source Semi-Empirical Model for 2D Mixer Ejector Noise Prediction J. Stone, B. Clark, and E. Krejsa 590 Development of a Jet Noise Prediction Method for

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ASCENT Project 59B Objective: JET NOISE MODELING AND

used by Project 59 jet noise modelers for the validation of low, medium, and high-fidelity jet noise prediction methods for supersonic transport applications (SST). Project Benefits: The validation of these prediction codes will give confidence in the noise prediction, which will aid in the design of low noise engines for reduced

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Impact of coherence decay on wavepacket models for

A comprehensive summary of subsonic jet-noise modelling using wavepackets can be found in the review of Jordan & Colonius (Reference Jordan and Colonius 2013). Wavepacket models have also been used for supersonic jet noise (Léon & Brazier Reference Léon and Brazier 2013; Sinha et al. Reference Sinha, Rodríguez, Brès and Colonius 2014). The

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AIAA 2003 3202 A Versatile Implementation of Acoustic

AIAA-2003-3165 Investigation of Extensions of the Four-Source Method for Predicting Forced Mixer Jet Noise. Garrison, L AIAA-2003-3168 Multiple-Source Semi-Empirical Model for 2D Mixer Ejector Noise Prediction. Stone, J print version. 601 AIAA-2003-3169 Development of a Jet Noise Prediction Method for Installed Jet Configurations

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Jet noise modeling method, jet noise analyzing method, and

2. The jet noise source modeling method according to claim 1, wherein the point sound sources are set along a jet axis of the jet stream. 3. A jet noise analyzing method of analyzing a sound field around a jet stream by using a jet noise source model created by the jet noise

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Transformers: Basics, Maintenance, and Diagnostics

Transformers: Basics, Maintenance, and Diagnostics vii Contents (continued) Page 4. Oil-Filled Transformer Inspections (continued) 4.3 Winding Temperature Thermometers..

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Jet nozzle mixer - Anderson, Jack H

An external jet nozzle mixer includes identically formed lobes. The external mixer works with the internal mixer further to mix the engine internal bypass flow with the internal jet engine core flow to level the disparate flow velocities, to reduce the peak velocities from the jet engine core and increase the lower bypass velocities of the engine internal bypass flow, and thereby reduce noise.

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