Open Access
Airframe Noise Prediction Method
TLDR
In this article, a noise component method is presented for calculating airframe noise, where the clean wing and tail surface noise is represented as a lift dipole normal to the deflected flap, with amplitude and spectrum given by a correlation of flyover data.Abstract:
: A noise component method is presented for calculating airframe noise. Noise from clean wing and tail surface is represented as trailing edge noise caused by the turbulent boundary layer. Landing gear noise is given by an empirical representation of model data. Trailing edge flap noise is modeled as a lift dipole normal to the deflected flap, with amplitude and spectrum given by a correlation of flyover data. Measured flyover data for the Prue-2 sailplane, Aero Commander Shirke general aviation airplane, Lockheed JetStar business jet, Boeing 747 commerical jet, and Convair F-106B delta wing airplane are used as test cases. These spectra are compared with predictions by this method and the NASA ANOPP total aircraft method and drag element method. Methods for reducing various components of airframe noise are examined and evaluated.read more
Citations
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Journal ArticleDOI
Almost 40 Years of Airframe Noise Research: What Did We Achieve?
TL;DR: In this article, the authors provide a concise survey of the achievements in airframe noise source description and reduction over the last 40 years worldwide and provide examples but do not claim to be complete.
Journal ArticleDOI
Aircraft noise reduction technologies: A bibliographic review
TL;DR: In this article, a bibliographical review of the main technologies employed for the mitigation of aircraft noise is presented, according to a component-based approach, analytical and semi-empirical models of the aeroacoustic mechanisms involved in the noise generation from airframe and engine components are presented as a key element of the noise reduction technology.
Aircraft noise prediction program theoretical manual, part 2
TL;DR: The prediction of data which affect noise generation and propagation is addressed, including the aircraft flight dynamics, the source noise parameters, and the propagation effects.
Proceedings ArticleDOI
Aircraft Optimization for Minimal Environmental Impact
Nicolas E. Antoine,Ilan Kroo +1 more
TL;DR: In this article, the authors investigate the trade-off between operating cost and environmental acceptability of commercial aircraft and determine the feasibility of including noise and emissions constraints in the early design of the aircraft and mission.
Proceedings ArticleDOI
Design of the Next Generation Aircraft Noise Prediction Program: ANOPP2
Leonard V. Lopes,Casey L. Burley +1 more
TL;DR: The requirements, constraints, and design of NASA's next generation Aircraft NOise Prediction Program (ANOPP2) are introduced in this article, which is designed to facilitate the combination of acoustic approaches of varying fidelity for the analysis of noise from conventional and unconventional aircraft.
References
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Prediction of Airfoil Tone Frequencies
TL;DR: It has been demonstrated that the use of CSOR b results in material savings in computational times over theuse of Jh, GSh, andSORh.
Journal ArticleDOI
Experimental Evaluation of Theories for Trailing Edge and Incidence Fluctuation Noise
TL;DR: In this paper, a flat-plate airfoil with flush-mounted surface pressure transducers was tested in an anechoic wind tunnel at velocities of 31.5-177 m/sec (108-580 fps) and nominal 4 and 6°7o grid-generated turbulence levels.