US3566989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sound suppression nozzle structure for fan jet aircraft engine
Assignee: Rohr Inc
•
Filing: 1969-12-01
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Granted: 1971-03-02
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Expires: 1989-12-01
Abstract
Abstract A turbofan jet aircraft engine has a fan air plenum chamber housing mounted coaxially of the engine and downstream of the engine exhaust duct, the downstream end of the housing having an opening therein to form a central fan air discharge nozzle. A plurality of circumferentially spaced fan air inlet tubes communicate the housing with the usual annular fan air duct surrounding the engine, and a plurality of short ducts, interposed in interdigitated relation between the fan air inlet tubes, discharge the remainder of the fan air into the main stream of primary exhaust gases closely adjacent the engine. A plurality of fan air nozzle tubes also radiate from the plenum chamber housing, and extend downstream to surround the central nozzle. A fluted tailpipe, coextensive with the outer wall of the annular fan air engine duct, surrounds the plenum chamber and all of the ducts and nozzles. A retractable ejector ring, preferably acoustically lined, is mounted for movement from retracted position surrounding the tailpipe to deployed position just downstream of the nozzle exit plane.
Inventors
- 👤 Peter H Ellis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:47
CPC Classifications
F; F02; F02K; F02K1/00; F02K1/40; F02K1/36
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
208 words
A sound suppression nozzle structure for a turbofan jet aircraft engine having an axial exhaust duct and a fan air duct, with a rear rotor bearing support centered in the downstream end of said exhaust duct, said nozzle structure comprising: a plenum chamber housing mounted coaxially of the engine and downstream of the rotor bearing support, the downstream end of the housing being open and forming a central fan air exhaust nozzle; a plurality of fan air inlet tubes spaced apart in the downstream end of the fan air duct and communicating the fan air duct with the interior of the housing; a plurality of short fan air ducts opening from the fan air duct directly into exhaust gases from the engine exhaust duct and mounted in interdigitated relation between the fan air inlet tubes, said short ducts terminating upstream of the central fan air exhaust nozzle; a plurality of fan air nozzle tubes mounted on and sealed to said housing and in open communication with the interior thereof, said nozzle tubes extending downstream and surrounding the central nozzle; and a tail pipe mounted coextensively with the exterior of the downstream end of the engine fan air duct, said tailpipe enclosing said housing and said tubes and nozzles.
Claim 2
Dependent Claim
208 words
A sound suppression nozzle structure for a turbofan jet aircraft engine having an axial exhaust duct and a fan air duct, with a rear rotor bearing support centered in the downstream end of said exhaust duct, said nozzle structure comprising: a plenum chamber housing mounted coaxially of the engine and downstream of the rotor bearing support, the downstream end of the housing being open and forming a central fan air exhaust nozzle; a plurality of fan air inlet tubes spaced apart in the downstream end of the fan air duct and communicating the fan air duct with the interior of the housing; a plurality of short fan air ducts opening from the fan air duct directly into exhaust gases from the engine exhaust duct and mounted in interdigitated relation between the fan air inlet tubes, said short ducts terminating upstream of the central fan air exhaust nozzle; a plurality of fan air nozzle tubes mounted on and sealed to said housing and in open communication with the interior thereof, said nozzle tubes extending downstream and surrounding the central nozzle; and a tail pipe mounted coextensively with the exterior of the downstream end of the engine fan air duct, said tailpipe enclosing said housing and said tubes and nozzles.
Claim 3
Dependent Claim
33 words
A sound suppression nozzle structure as claimed in claim 1 wherein the wall of the housing is a surface of revolution and the housing is secured coaxially to the rear rotor bearing support.
Claim 4
Dependent Claim
28 words
A sound suppression nozzle structure as claimed in claim 2 wherein the housing is in the form of a necked vase with the neck portion thereof directed downstream.
Claim 5
Dependent Claim
31 words
A sound suppression nozzle structure as claimed in claim 3 wherein the fan air inlet tubes have their downstream ends attached to, and opening into the housing near the base thereof.
Claim 6
Dependent Claim
33 words
A sound suppression nozzle structure as claimed in claim 3 wherein a conical base is provided in the housing and said base extends downstream coaxially within the housing with its apex directed downstream.
Claim 7
Dependent Claim
36 words
A sound suppression nozzle structure as claimed in claim 1 wherein the nozzle tubes terminate at their downstream ends in a circle around the central nozzle on a nozzle exit plane defined by the central nozzle.
Claim 8
Dependent Claim
24 words
A sound suppression nozzle structure as claimed in claim 6 wherein the tailpipe also terminates at its downstream end on the nozzle exit plane.
Claim 9
Dependent Claim
43 words
A sound suppression nozzle structure as claimed in claim 1 wherein a plurality of flutings are provided in the downstream terminal portion of the tailpipe for drawing streams of ambient atmospheric air into the periphery of the exhaust gases discharged from the tailpipe.
Claim 10
Dependent Claim
55 words
A sound suppression nozzle structure as claimed in claim 1 wherein an ejector ring is movably mounted coaxially of the engine for axial movement from a retracted position surrounding the fan air duct and upstream of the downstream end of the tailpipe, to a deployed position just downstream of the downstream end of the tailpipe.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-01 | 1974-08-31 | 1975-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-01 | 1978-08-31 | 1979-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-01 | 1982-08-31 | 1983-03-02 | $7700.00 | Window Closed / Lapsed |