Exhaust nozzle and method for changing exhaust flow path

Patent metadata

Field	Value
Publication number	US-9976515-B2
Application number	US-201414271584-A
Country	US
Kind code	B2
Filing date	May 7, 2014
Priority date	Aug 19, 2013
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

Provided is an exhaust nozzle and a method for changing an exhaust flowpath, whereby noise can be reduced by using a simple and light-weight mechanism without increasing the complexity and size of the structure of the exhaust nozzle, and furthermore, the efficiency during cruising at supersonic speeds can be improved. The rear end side of main nozzle pieces 110 of an exhaust nozzle 100 are provided swingably in an inward and outward direction of an exhaust flow path 101 , about an open/close bend section 111 to the rear of an engine, coupling nozzle pieces 120 are coupled bendably to adjacent main nozzle pieces 110 on either side, and when the main nozzle pieces 110 are swung inside the exhaust flow path 101 , the coupling nozzle pieces 120 form projecting sections 102 inside the exhaust flow path 101.

First claim

What is claimed is:

1. An exhaust nozzle extending to the rear of an engine and constituting an exhaust flow path,
wherein the exhaust nozzle has a throttle section, a plurality of main nozzle pieces and at least one coupling nozzle piece,
the throttle section is formed in a truncated conical shape in which a cross-sectional area becomes smallest at a rear end of the throttle section,
a rear end portion of each of the main nozzle pieces is provided swingably in an inward and outward direction of the exhaust flow path about an open/close bend section to the rear of the engine, and the open/close bend section is formed at the rear end of the throttle section of the engine,
the coupling nozzle piece is disposed between adjacent main nozzle pieces and is coupled bendably to the main nozzle pieces on either side thereof, the coupling nozzle piece is coupled bendably to the main nozzle pieces at a side bend section, and the coupling nozzle piece has a central bend section which is capable of forming a bent projecting section inside the exhaust flow path in conjunction with a movement of each of the main nozzle pieces,
when the main nozzle pieces are swung outward from the exhaust flow path, the coupling nozzle piece forms a flat surface having no projecting section inside the exhaust flow path, and the cross-sectional area of the rear end portion of the exhaust flow path is wider than the cross-sectional area at the position of the open/close bend section of the exhaust flow path, and
when the main nozzle pieces are swung inside the exhaust flow path, the coupling nozzle piece forms the bent projecting section inside the exhaust flow path.

2. The exhaust nozzle according to claim 1 , wherein, when the main nozzle pieces are swung inside the exhaust flow path, the cross-sectional area of the rear end portion of the exhaust flow path is no more than the cross-sectional area at the position of the open/close bend section of the exhaust flow path.

3. The exhaust nozzle according to claim 1 , wherein each of the open/close bend section, the side bend section and the central bend section has a hinge.

4. The exhaust nozzle according to claim 1 , wherein the plurality of main nozzle pieces and the coupling nozzle pieces constitute the exhaust nozzle, and the exhaust nozzle constitutes the whole circumference of the exhaust flow path to the rear of the engine.

5. The exhaust nozzle according to claim 4 , wherein,
the exhaust nozzle has three or more coupling nozzle pieces,
each of the open/close bend section extends to the circumferential direction of the exhaust flow path at the rear of the throttle section,
each of the main nozzle pieces has a rear end edge portion extending the circumferential direction at the rear end portion of the exhaust flow path,
each of the coupling nozzle pieces is coupled bendably to the main nozzle pieces from a line connecting a first end portion of the open/close bend section in the circumferential direction to a second end portion of the rear end edge portion in the circumferential direction,
when the main nozzle pieces are swung inside the exhaust flow path, the coupling nozzle piece forms the bent projecting section inside the exhaust flow path has a shape approximating that of a truncated cone formed by the main nozzle pieces.

6. The exhaust nozzle according to claim 1 , wherein, when the main nozzle pieces are swung inside the exhaust flow path and the rear end portion of the exhaust flow path is narrowest, the cross-sectional area of each portion from the position of the open/close bend section of the exhaust flow path to the rear end portion of the exhaust flow path is substantially constant.

7. The exhaust nozzle according to claim 1 , wherein,
the main nozzle pieces are swung by driving force from outside, and
the coupling nozzle pieces are bended by swinging movement of the main nozzle pieces.

8. The exhaust nozzle according to claim 1 , wherein,
the bent projecting section inside the exhaust flow path formed by the coupling nozzle pieces forms a triangular conical shape.

9. The exhaust nozzle according to claim 8 , wherein,
the coupling nozzle pieces form the bent projecting section with the triangular conical shape so that a Mach speed distribution of exhaust jet exhausted from the rear end portion of the exhaust flow path is a notched distribution.

10. An exhaust nozzle extending to the rear of an engine of a supersonic aircraft and constituting an exhaust flow path, the exhaust nozzle comprising:
a throttle section;
a plurality of main nozzle pieces; and
at least one coupling nozzle piece, wherein,
the throttle section is formed in a truncated conical shape in which a cross-sectional area becomes smallest at a rear end of the throttle section,
a rear end portion of each of the main nozzle pieces is provided swingably in an inward and outward direction of the exhaust flow path about an open/close bend section to the rear of the engine, and the open/close bend section is formed at the rear end of the throttle section,
the coupling nozzle piece is disposed between adjacent main nozzle pieces and is coupled bendably to the main nozzle pieces from either side thereof, the coupling nozzle piece is coupled bendably to the main nozzle pieces at a side bend section, and the coupling nozzle piece has a central bend section which is capable of forming a bent projecting section inside the exhaust flow path in conjunction with a movement of each of the main nozzle pieces,
when the supersonic aircraft cruises at supersonic speeds, the main nozzle pieces are swung outward from the exhaust flow path, the coupling nozzle piece forms a flat surface having no projecting section inside the exhaust flow path, and the cross-sectional area of the rear end portion of the exhaust flow path is wider than the cross-sectional area at the position of the open/close bend section of the exhaust flow path, and
when the supersonic aircraft takes off and lands, the main nozzle pieces are swung inside the exhaust flow path and the coupling nozzle piece forms the bent projecting section inside the exhaust flow path.

11. The exhaust nozzle according to claim 10 , wherein, when the supersonic aircraft takes off and lands, the main nozzle pieces are swung inside the exhaust flow path and the cross-sectional area of the rear end portion of the exhaust flow path is no more than the cross-sectional area at the position of the open/close bend section of the exhaust flow path.

12. The exhaust nozzle according to claim 10 , wherein each of the open/close bend section, the side bend section and the central bend section has a hinge.

13. The exhaust nozzle according to claim 10 , wherein the plurality of main nozzle pieces and the coupling nozzle pieces constitute the exhaust nozzle, and the exhaust nozzle constitutes the whole circumference of the exhaust flow path to the rear of the engine.

14. The exhaust nozzle according to claim 10 , wherein, when the supersonic aircraft takes off and lands, the main nozzle pieces are swung inside the exhaust flow path and the rear end portion of the exhaust flow path is narrowest and the cross-sectional area of each portion from the position of the open/close bend section of the exhaust flow path to the rear end portion of the exhaust flow path is substantially constant.

15. The exhaust nozzle according to claim 13 , wherein,
the exhaust nozzle has three or more coupling nozzle pieces,
each of the open/close bend section extends to the circumferential direction of the exhaust flow path at the rear of the throttle section,
each of the main nozzle pieces has a rear end e

Assignees

• Japan Aerospace Exploration

Inventors

• Akatsuka Junichi
• Watanabe Yasushi

Classifications

• F02K1/08 Primary

  by axially moving or transversely deforming an internal member, e.g. the exhaust cone · CPC title

• Y02T50/671

  Cross-Sectional Technologies · mapped topic

• F02K1/46

  Nozzles having means for adding air to the jet or for augmenting the mixing region between the jet and the ambient air, e.g. for silencing (F02K1/28, F02K1/36, F02K1/38 take precedence) · CPC title

• Y02T50/60

  Efficient propulsion technologies, e.g. for aircraft · CPC title