US 11,674,481 B2
Acoustic resonator
Pascal Guerry, Seppois-le-haut (FR); Adrien Eustache, Port (FR); and Michel Robinault, Sene (FR)
Assigned to AKWEL, Champfromier (FR)
Filed by AKWEL, Champfromier (FR)
Filed on Feb. 5, 2020, as Appl. No. 16/782,722.
Claims priority of application No. 1901098 (FR), filed on Feb. 5, 2019.
Prior Publication US 2020/0248660 A1, Aug. 6, 2020
Int. Cl. F02M 35/12 (2006.01)
CPC F02M 35/1266 (2013.01) [F02M 35/1216 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A resonator for attenuating noise in a duct, the duct having an internal channel for the flow of a fluid and a reference axis, the resonator comprising:
a generally annular compartment extending around the internal channel, the generally annular compartment forming a generally annular Helmholtz resonance cavity;
an orifice forming a neck connecting the generally annular Helmholtz resonance cavity with the internal channel, the orifice extending longitudinally along a circumference of the internal channel; and
a generally tubular insert member around the reference axis intended to be inserted inside the duct which delimits, internally, the internal channel and, externally, with the duct, a space comprising the generally annular compartment,
wherein the generally annular compartment presents an inner structure with a revolution asymmetry about the reference axis, the revolution asymmetry being adapted to generate a phase shift of an acoustic pressure wave propagating in the generally annular Helmholtz resonance cavity relative to an acoustic pressure wave propagating in the internal channel, and
wherein the insert member has a tubular intermediate portion and end portions which are respectively convergent and divergent to and from the intermediate portion.