Variable geometry nozzle

• US 4,754,924 A
• Filed: 04/03/1987
• Issued: 07/05/1988
• Est. Priority Date: 04/03/1987
• Status: Expired due to Fees

• Current Assignee: Aubrey J. Shannon
• Original Assignee: Aubrey J. Shannon
• Inventors: Shannon, Aubrey J.
• Primary Examiner(s): Kashnikow, Andres
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/033,620
• Time in Patent Office: 459 Days
• Field of Search: 239/127.3, 239/265.13, 239/265.17, 239/265.33, 181/215, 181/220, 60/230
• US Class Current: 239/127.3
• CPC Class Codes: B64D 33/04 of exhaust outlets or jet pipes exhaust outlets for combustion engines in general F01N; jet pipes or nozzles for jet-propulsion plants per se F02K; plants characterised by the form or arrangement of the jet pipe or nozzle F02K ; attitude, flight direction, or altitude control by jet reaction B64C
• CPC Class Codes: F02K 1/383 with retractable elements
• CPC Class Codes: F02K 1/50 Deflecting outwardly a portion of the jet by retractable scoop-like baffles

Abstract

A jet engine nozzle operable in a cruise setting and a noise attenuation setting. In the cruise setting the nozzle provides simple through flow. In the noise attenuation setting some ambient flow is ducted into the through flow and some through flow is ducted into ambient flow. The nozzle comprises a fixed portion and a movable portion, rotatable a part of a revolution about the fixed portion. The nozzle comprises two rotary valves which operate in unison, a sleeve type valve and a face type. The sleeve type comprises cooperating lobed openings in the fixed portion and in a forward segment of the movable portion, the movable portion fitting telescopically over the fixed portion. The rotary type comprises the exit faces of aft facing lobes in the fixed portion and cooperating entrance faces of lobes in the aft segment of the movable portion. In the attenuation setting both valves are open. The sleeve valve ducts ambient flow into the flow through the nozzles and the face valve allows flow into ambient air from the flow through the nozzle. In the cruise setting both valves are closed. Opening and closing are powered by an appropriate state-of-the-art actuation apparatus and system and involve rotating the movable portion a part of a revolution so that either the various openings register with each other to make the valves open or register with structure which obstructs the opening and closes the valves, providing simple through flow. The nozzle may also be effectively used in modifying the infra-red signature of an engine.

Claims

1. A nozzle for a jet engine operating in ambient air, said nozzle having a flow through passage for effluent gases and comprising:

a first rotary valve of the sleeve type, having an open state and a closed state,

a second rotary valve of the face type, having an open state and a closed state,

a fixed portion and

a movable portion,

said movable portion being assembled with and movable relative to said fixed portion to a first setting and second setting,

means for moving said movable portion to said first setting and to said second setting,

said first and second valves being in said open states when said movable portion is in said first setting and in said closed states when said movable portion is in said second state,

said first rotary valve providing at least one first passage from said ambient air to said flow through passage when said first valve is in said open state and said second rotary valve providing at

least one passage from said flow through passage to said ambient air when said second valve is in said open state,

said at least one first and second passages being closed off when said first and second valves are in said closed states,

whereby, when said nozzle is in said first setting said first and second valves are in said open states and air flows through said at least one first passage into said flow through passage and gasses flow through said at least one second passage into said ambient air.

2. The nozzle of claim 1 in which said passages comprise openings having lobes and said openings are rectangular.

3. A variable geometry nozzle operable in ambient air and having a flow-through passage and being settable in a cruise setting and an attenuation setting and being operable in a cruise mode and an attenuation mode, said nozzle comprising:

a first, sleeve type rotary valve,

a second, face type rotary valve,

means for setting said nozzle in said cruise setting and said supression setting,

said first valve providing passages from said ambient air into said flow-through passage,

said second valve providing passages from said flow-through channel to said ambient air,

said first and second valves being open in said attenuation setting and closed in said cruise setting,

whereby in said attenuation setting said passages provided by said first valve allow flow from said ambient air into said flow-through passage and said passages provided by said second valve allow flow from said flow-through passage to said ambient air and in said cruise setting all said passages are closed off.

5. The nozzle of claim 3 in which said openings have isosceles triangles shapes.

6. The nozzle of claim 3 in which said openings have trapezoidal shapes.

7. The nozzle of claim 3 in which said openings have rectangular shapes.

4. A variable geometry nozzle for a jet engine having an attenuation setting and a cruise setting and being operable in a sound attenuation mode and a cruise mode and having an outflow end, said nozzle comprising first and second rotary valves,

said nozzle having a gas flow passage and comprising a fixed portion and a movable portion surrounding said passage, said fixed and movable portion being essentially cylindrical,

said fixed portion being attached to said outflow end and having a first cylindrical wall having an outside diameter, a first forward end, first aft end, an aft planar face, a first length and a first plurality of first openings in said first wall, said first openings being spaced radially equidistant from each other and having first spaces between them,

said first spaces having first widths and said first openings having second widths, said first and second widths being essentially equal,

said first openings being provided with lobes extending from said first wall into said passage and having exit faces coplanar with said aft face,

said movable portion having a second length, a forward segment and an aft segment, said forward segment having a cylindrical wall having an inside diameter, a second forward end having a planar face, a third length equal to said first length, said aft segment having a wall which is a surface of revolution, said forward and aft sections joining in a plane of adjoinment which is perpendicular to said second cylindrical wall,

said inside diameter being greater than said outside diameter by an amount in the range of 0.1 to 1% of said outside diameter,

said second plurality of openings being in said forward segment and spaced radially equidistant from each other and having second spaces between them, said second openings having third widths and said second spaces having fourth widths, said third and fourth widths being essentially equal,

said third plurality of openings being in said aft segment and spaced radially equidistant from each other and having third spaces between them, said third openings having fifth widths and said third spaces having sixth widths, said fifth and sixth widths being essentially equal,

said second openings being provided with lobes extending outwardly from said second cylindrical wall and having entrance faces coplanar with said forward face,

said third openings being provided with lobes extending into said passage and having entrance faces coplanar with said plane of adjoinment,

said third openings being in longitudinal alignment with said second spaces in said forward segment,

said second portion being rotatably attached to said fixed portion with said forward segment telescopically surrounding said fixed portion, whereby said first openings and said second openings are positioned relative to each other to function as said first rotary valve and said exit faces of said lobes provided on said first openings and said entrance faces of said lobes provided on said third openings are positioned relatively to cooperate in said plane of adjoinment to function as said second rotary valve,

means being provided to rotate said movable portion relative to said fixed portion interchangeably between said suppression setting and said cruise setting,

whereby with said movable portion set in said attenuation setting:

said first and second openings are coincident and they, in conjunction with said lobes provided for said openings, provide passages for said ambient air to flow from outside said nozzle into said passage and said lobes provided on said second openings and said second openings provide passages for gas flow from said passage through said second wall into said ambient air and with said rotary valves being open said nozzle is operable in said sound attenuation mode, and

with said movable portion set in said cruise setting;

said second openings are aligned with said first spaces and said exit faces of

said lobes provided on said first openings are aligned in said plane of adjoinment with said entrance faces of said lobes provided on said third openings, so that both rotary valves are closed and said nozzle is in said cruise mode.