CN110566363A

CN110566363A - Engine exhaust system

Info

Publication number: CN110566363A
Application number: CN201910829391.0A
Authority: CN
Inventors: 卫永斌; 段卓毅
Original assignee: Xian Aircraft Design and Research Institute of AVIC
Current assignee: Xian Aircraft Design and Research Institute of AVIC
Priority date: 2019-09-03
Filing date: 2019-09-03
Publication date: 2019-12-13
Anticipated expiration: 2039-09-03
Also published as: CN110566363B

Abstract

The application belongs to the technical field of the structural design of an aircraft engine exhaust system, and particularly relates to an engine exhaust system which comprises a spiral spray pipe, wherein the inlet of the spiral spray pipe is used for being butted with an engine exhaust port, and the spiral spray pipe can shield high-temperature components such as an aircraft engine turbine and the like by a smaller total offset distance; on the other hand, high-temperature and low-temperature airflow of the internal and external culvert of the aeroengine can flow into the spiral spray pipe from the exhaust port of the engine, and the airflow flowing into the spiral spray pipe can be effectively overturned and mixed in the flowing process along the spiral spray pipe, so that the temperature of the high-temperature airflow can be reduced, and finally, the temperature of the airflow discharged from the spiral spray pipe is uniform, and the temperature distortion is reduced.

Description

Engine exhaust system

Technical Field

the application belongs to the technical field of aero-engine exhaust system structural design, and particularly relates to an engine exhaust system.

background

at present, aircraft exhaust system is mostly the axial symmetry formula or binary directly spouts the tubular, it does not possess the ability of sheltering from high temperature part such as aeroengine turbine, the improvement of its stealthy performance has been restricted, adopt the exhaust system of S type or many S type tandem types can realize the sheltering from to high temperature part such as aeroengine turbine to a certain extent, but need great gross offset, aerodynamic loss is serious, and the high and low temperature air current of inside and outside the culvert of engine lacks effectual upset tragic mixing in exhaust system, the jet flow temperature is difficult to obtain effective cooling in core area, jet flow temperature distortion becomes big.

Accordingly, a technical solution is desired to overcome or at least alleviate at least one of the above-mentioned drawbacks of the prior art.

Disclosure of Invention

It is an object of the present application to provide an engine exhaust system to overcome or mitigate the technical disadvantages of at least one of the above aspects.

The technical scheme of the application is as follows:

an engine exhaust system comprising:

The inlet of the spiral spray pipe is used for being butted with the exhaust port of the engine.

according to at least one embodiment of the present application, the engine further comprises an inflow pipe, an inlet of which is used for being butted with an exhaust port of the engine, and an outlet of which is butted with an inlet of the spiral spray pipe; the radial cross section of the inflow pipe gradually shrinks from the inlet to the outlet.

According to at least one embodiment of the present application, further comprising an outflow pipe, an inlet of which is butted against an outlet of the spiral nozzle; the radial cross-section of the outflow conduit gradually tapers from its inlet to its outlet.

according to at least one embodiment of the present application, the radial cross-section is the same throughout the spiral nozzle.

according to at least one embodiment of the application, the axis of the inflow tube coincides with the axis of the outflow tube.

according to at least one embodiment of the present application, the inlet of the inflow pipe is circular and the outlet thereof is circular; the inlet of the outflow pipe is circular and the outlet is elliptical. Or the inlet of the inflow pipe is circular, and the outlet of the inflow pipe is circular; the inlet of the outflow pipe is circular and the outlet is elliptical.

according to at least one embodiment of the present application, the length of the helical lance is 3-8 times the diameter of the engine exhaust.

according to at least one embodiment of the present application, the lengths of the inflow pipe and the outflow pipe are 1.5 to 2.5 times the diameter of the engine exhaust port.

according to at least one embodiment of the present application, there are two inflow pipes, each inflow pipe having an inlet for interfacing with a corresponding one of the engine exhaust ports;

The inlet of each spiral spray pipe is correspondingly butted with the outlet of one inflow pipe; the two spiral spray pipes are mutually wound;

The outlet pipe has two, and the inlet of each outlet pipe is correspondingly butted with the outlet of one spiral spray pipe.

The application has at least the following beneficial technical effects:

The spiral jet pipe and the spiral jet pipe are connected with the exhaust port of the engine in a butt joint mode, and on one hand, the spiral jet pipe can shield high-temperature components such as an aircraft engine turbine and the like by a small total offset distance; on the other hand, high-temperature and low-temperature airflow of the internal and external culvert of the aeroengine can flow into the spiral spray pipe from the exhaust port of the engine, and the airflow flowing into the spiral spray pipe can be effectively overturned and mixed in the flowing process along the spiral spray pipe, so that the temperature of the high-temperature airflow can be reduced, and finally, the temperature of the airflow discharged from the spiral spray pipe is uniform, and the temperature distortion is reduced.

Drawings

FIG. 1 is a schematic block diagram of an engine exhaust system provided by an embodiment of the present application;

FIG. 2 is a schematic view of the combination of the inlet and outlet of the inflow tube and the inlet and outlet shapes of the outflow tube according to the embodiment of the present application;

FIG. 3 is a schematic view of the combination of the inlet and outlet of an inflow tube and the inlet and outlet shapes of an outflow tube according to another embodiment of the present disclosure;

wherein:

1-a spiral spray pipe; 2-an inflow pipe; 3-an outflow pipe; 21-inlet of inflow tube; 22-outlet of inflow tube; 31-inlet of outflow pipe; 32-outlet of the outflow pipe.

Detailed Description

The present application will be described in further detail with reference to the following drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant application and are not limiting of the application. It should be noted that, for convenience of description, only the portions related to the present application are shown in the drawings.

it should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

it should be noted that in the description of the present application, the terms of direction or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, which are merely for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Furthermore, it should be noted that, in the description of the present application, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as being fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those skilled in the art as the case may be.

the present application is described in further detail below with reference to fig. 1 to 3.

An engine exhaust system, comprising:

The inlet of the spiral nozzle 1 is used for being in butt joint with the exhaust port of the engine.

For the engine exhaust system disclosed in the above embodiment, it is easily understood by those skilled in the art that high-temperature and low-temperature airflows of an internal bypass and an external bypass of an aircraft engine can flow into the spiral nozzle 1 from an engine exhaust port, and the gas entering the spiral nozzle 1 can be effectively turned and mixed in the flowing process along the spiral nozzle, so that the temperature of the high-temperature airflow therein can be effectively reduced, and finally the temperature of the exhaust airflow therefrom is uniform, thereby reducing the temperature distortion; in addition, the spiral nozzle 1 can realize shielding of high-temperature components such as an aircraft engine turbine and the like by a smaller total offset distance.

In some optional embodiments, the device further comprises an inflow pipe 2, the inlet of which is used for being butted with an exhaust port of the engine, and the outlet of which is butted with the inlet of the spiral nozzle 1; the radial cross section of the inflow pipe 2 gradually narrows from its inlet towards its outlet.

With regard to the engine exhaust system disclosed in the above embodiment, it is easily understood by those skilled in the art that the air flow flowing out from the engine exhaust port can flow into the inflow pipe 2 along the normal direction of the inlet of the inflow pipe 2, the air flow flowing into the inflow pipe 2 flows along the inflow pipe 2, the flow velocity of the air flow therein continuously increases due to the gradually reduced cross-sectional area of the inflow pipe 2 until the air flow flows into the inlet of the spiral nozzle 1 along the normal direction of the outlet of the inflow pipe 2, and the flow velocity of the air flow flowing through the inflow pipe 2 can be generally selected to increase by 19% to 45% so as to effectively reduce the aerodynamic loss of the air flow.

In some optional embodiments, the device further comprises an outflow pipe 3, the inlet of which is butted with the outlet of the spiral nozzle 1; the radial cross-section of the outflow pipe 3 gradually narrows from its inlet towards its outlet.

With respect to the engine exhaust system disclosed in the above embodiments, it is easily understood by those skilled in the art that the airflow flowing out from the outlet of the spiral nozzle 1 can flow into the outflow pipe 3 along the normal direction of the inlet of the outflow pipe 3, the airflow flowing into the outflow pipe 3 flows along the outflow pipe 3, the flow velocity of the airflow therein continuously increases due to the gradually reduced cross-sectional area of the outflow pipe 3 until the airflow flows out along the normal direction of the outlet of the outflow pipe 3, and the flow velocity of the airflow flowing through the outflow pipe 3 can be generally selected to reach subsonic velocity, so as to effectively reduce the aerodynamic loss of the airflow.

in some alternative embodiments, the axis of the inflow tube 2 coincides with the axis of the outflow tube 3.

With respect to the engine exhaust system disclosed in the above embodiment, it will be readily understood by those skilled in the art that the center point of the inlet of the inflow pipe 2 and the center point of the outlet of the outflow pipe 3 are on the same horizontal line, so that the yaw moment of the inlet of the inflow pipe 2 to the outlet of the outflow pipe 3 is zero.

In some alternative embodiments, the inlet of the inflow tube 2 is circular and its outlet is circular; the inlet of the outflow pipe 3 is circular and the outlet thereof is oval. Alternatively, the inlet of the inflow pipe 2 is circular and the outlet thereof is circular; the inlet of the outflow pipe 3 is circular and the outlet thereof is oval.

In some optional embodiments, the radial cross section of each part of the spiral nozzle 1 is the same, and the length of the spiral nozzle is 3-8 times of the diameter of the exhaust port of the engine, so that the spiral nozzle 1 has enough length, the fluid flowing through the spiral nozzle is fully turned and blended, and the flow field of the airflow can be stabilized and combed, the flow field separation is prevented, and the aerodynamic loss is reduced.

In some alternative embodiments, the length of the inlet pipe 2 and the outlet pipe 3 is 1.5 to 2.5 times the diameter of the engine exhaust port.

in some alternative embodiments, there are two inflow pipes 2, and each inlet of the inflow pipe 2 is used to interface with one engine exhaust port;

The number of the spiral spray pipes 1 is two, and the inlet of each spiral spray pipe 1 is correspondingly butted with the outlet of one inflow pipe 2; the two spiral spray pipes 1 are mutually wound;

The number of the outflow pipes 3 is two, and the inlet of each outflow pipe 3 is correspondingly butted with the outlet of one spiral spray pipe 1.

For the engine exhaust system disclosed in the above embodiment, as will be readily understood by those skilled in the art, the engine exhaust system is suitable for a double engine, and two spiral nozzles 1 of the engine exhaust system are designed to be wound around each other, so as to approximate to a twist shape, so that on one hand, the spiral nozzles can be combined with each other to enhance shielding of high-temperature components such as an aircraft engine turbine, and on the other hand, valuable space on the aircraft can be effectively saved.

so far, the technical solutions of the present application have been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of the present application is obviously not limited to these specific embodiments. Equivalent changes or substitutions of related technical features can be made by those skilled in the art without departing from the principle of the present application, and the technical scheme after the changes or substitutions will fall into the protection scope of the present application.

Claims

1. An engine exhaust system, comprising:

The inlet of the spiral spray pipe (1) is used for being butted with the exhaust port of the engine.

2. The engine exhaust system of claim 1,

The inlet of the inflow pipe (2) is butted with the exhaust port of the engine, and the outlet of the inflow pipe is butted with the inlet of the spiral spray pipe (1); the radial section of the inflow pipe (2) gradually shrinks from the inlet to the outlet.

3. the engine exhaust system of claim 2,

the device also comprises an outflow pipe (3), the inlet of which is butted with the outlet of the spiral spray pipe (1); the radial section of the outflow pipe (3) gradually shrinks from the inlet to the outlet.

4. the engine exhaust system of claim 3,

The radial sections of all parts of the spiral spray pipe (1) are the same.

5. The engine exhaust system according to claim 4,

The axis of the inflow tube (2) coincides with the axis of the outflow tube (3).

6. The engine exhaust system of claim 5,

The inlet of the inflow pipe (2) is circular, and the outlet of the inflow pipe is circular;

the inlet of the outflow pipe (3) is circular, and the outlet thereof is oval.

7. The engine exhaust system of claim 5,

The inlet of the outflow pipe (3) is circular, and the outlet thereof is oval.

8. the engine exhaust system of claim 5,

The length of the spiral spray pipe (1) is 3-8 times of the diameter of the exhaust port of the engine.

9. the engine exhaust system of claim 5,

The length of the inflow pipe (2) and the outflow pipe (3) is 1.5 to 2.5 times of the diameter of the exhaust port of the engine.

10. The engine exhaust system of claim 5,

The number of the inflow pipes (2) is two, and the inlet of each inflow pipe (2) is used for correspondingly butting with one engine exhaust port;

The number of the spiral spray pipes (1) is two, and the inlet of each spiral spray pipe (1) is correspondingly butted with the outlet of one inflow pipe (2); the two spiral spray pipes (1) are mutually wound;

The number of the outflow pipes (3) is two, and the inlet of each outflow pipe (3) is correspondingly butted with the outlet of one spiral spray pipe (1).