A hybrid computational model is presented to predict scattering and refractive effects on acoustic waves propagating through a boundary layer surrounding an aircraft fuselage. The fuselage is represented by an infinitely long cylinder with a noncircular cross section. The propagation effects through the boundary layer can be significant and should be included in noise predictions. The computational model uses finite elements to solve the acoustic pressure inside the boundary-layer area and boundary elements to calculate the pressure outside the boundary layer. An important advantage of the present model is that complicated geometries can be handled more easily than with prediction models that are based on analytical techniques. Most of these analytical prediction models are limited to circular cross shapes of fuselages. The purpose of the present investigation is to overcome this limitation and to assess the effects of noncircular geometries by comparing the pressure distributions with those of circular geometries. The computational model is applied to the noncircular cross section of a Fokker 50-like fuselage.
Hybrid computational model for noise propagation through a fuselage boundary layer
Hybrides Rechenmodell für die Schallfortpflanzung durch eine Grenzschicht am Flugzeugrumpf
AIAA Journal ; 34 , 9 ; 1785-1792
1996
8 Seiten, 16 Bilder, 12 Quellen
Article (Journal)
English
Flugzeugrumpf , Grenzschichtströmung , Schallfortpflanzung , mathematisches Modell , Streuung , Brechung , Schallwelle , Zylinder (Körper) , Querschnitt , Prognose , Finite-Elemente-Methode , Schalldruck , Rand-Elemente-Methode , geometrische Form , Druckverteilung , Luftschraube , Differenzialgleichung , Integralgleichung , Maschennetz , Scherströmung , Mach-Zahl , Anströmwinkel , Geschwindigkeitsverteilung , Verlagerung , Turbulenz
Hybrid Computational Model for Noise Propagation Through a Fuselage Boundary Layer
Online Contents | 1996
|A Hybrid Computational Model for Noise Propagation through a Fuselage Boundary Layer
British Library Conference Proceedings | 1995
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