Acoustics – Sound-modifying means – Muffler – fluid conducting type
Patent
1981-04-15
1983-10-18
Fuller, Benjamin R.
Acoustics
Sound-modifying means
Muffler, fluid conducting type
181222, 181241, 181286, 181292, F04F 1704, F01N 102, F01N 124
Patent
active
044100655
ABSTRACT:
An acoustic lining for a flow duct has a first perforate skin fixed to an underlying sound-absorbing layer. The first perforate skin is overlain by a second perforate skin which forms the wall of the flow duct. One of the skins is relatively moveable in a sliding sense with respect to the other skin so as to vary the acoustic impedance of the duct wall as the perforations in the respective skins slide into and out of registration with each other. This enables the acoustic impedance of the duct wall to be varied to suit the flow and noise conditions prevailing in the duct and so obtain optimum noise attenuation in the duct, which may be the intake duct of a turbofan aeroengine.
REFERENCES:
patent: 2320668 (1943-06-01), Smith
patent: 2988302 (1961-06-01), Smith
patent: 3630312 (1971-12-01), Woodward
patent: 3937590 (1976-02-01), Mani
patent: 4104002 (1978-08-01), Ehrich
patent: 4235303 (1980-11-01), Dhoore et al.
patent: 4294329 (1981-10-01), Rose et al.
Fuller Benjamin R.
Rolls-Royce Limited
LandOfFree
Multi-layer acoustic linings does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multi-layer acoustic linings, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multi-layer acoustic linings will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1285550