An active noise control model for reducing aircraft interior noise has been evaluated. The structural noise transmission properties of an aircraft fuselage were modeled as a flexible cylinder excited by external acoustic dipoles simulating, the noise produced by twin propellers. The amplitudes of an internal distribution of monopole control source were determined such that the area-weighted, mean-square acoustic pressure was minimized in the propeller plane. The noise control model was evaluated at low frequencies corresponding to the blade passage frequency and the first few harmonics of a typical turboprop aircraft. Interior noise reductions up to 20 dB were achieved over a substantial region of the cylindrical cross section, with just a few monopole control sources.
Active control of propeller-induced noise fields inside a flexible cylinder
Aktive Geräuschkontrolle von propellerinduzierten Schallfeldern im Innern eines flexiblen Zylinders
AIAA Journal ; 28 , 8 ; 1374-1380
1990
7 Seiten, 7 Bilder, 2 Tabellen, 10 Quellen
Article (Journal)
English
Online Contents | 2000
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