US 11,745,887 B2
Multifrequency absorption acoustic panel for an aircraft nacelle
Alain Porte, Toulouse (FR); Jacques Lalane, Toulouse (FR); Arnaud Bourhis, Toulouse (FR); and Florent Mercat, Toulouse (FR)
Assigned to Airbus Operations (S.A.S.), Toulouse (FR)
Filed by Airbus Operations (S.A.S.), Toulouse (FR)
Filed on Nov. 6, 2020, as Appl. No. 17/91,604.
Claims priority of application No. 1912487 (FR), filed on Nov. 7, 2019.
Prior Publication US 2021/0237890 A1, Aug. 5, 2021
Int. Cl. B64D 33/02 (2006.01); G10K 11/172 (2006.01); G10K 11/168 (2006.01)
CPC B64D 33/02 (2013.01) [G10K 11/168 (2013.01); G10K 11/172 (2013.01); B64D 2033/0206 (2013.01)] 15 Claims
OG exemplary drawing
 
1. An acoustic panel for an aircraft nacelle, comprising, from a central axis of the nacelle toward an exterior of the nacelle:
a resistive skin that forms a visible face of an interior duct of the nacelle, wherein the resistive skin is microperforated to have sound absorbing holes;
a core adapted to damp sound waves, the core comprising a first damping stage and a second damping stage which are separated from each other by a septum, wherein the septum is a planar wall that is formed with communication holes that extend between the first and second damping stages; and
a back skin configured to provide mechanical strength for the acoustic panel;
wherein a thickness of the septum is greater than a thickness of the resistive skin.