Support plate type supersonic combustion chamber coupled with wall surface sweeping nozzle

Abstract

The invention discloses a support plate type supersonic combustion chamber coupled with wall surface sweeping nozzles, which relates to the technical field of scramjet engines and comprises a central support plate and a plurality of wall surface sweeping nozzles. The other end of the combustion chamber body is an air outlet end; the center supporting plate is fixedly arranged in the combustion chamber body, and a plurality of fuel spraying holes used for spraying fuel into the combustion chamber body are formed in the center supporting plate. The sweeping nozzles are arranged on the inner wall of the combustion chamber body in the circumferential direction and used for spraying fuel into the combustion chamber body in a sweeping mode. According to the supporting plate type supersonic combustion chamber coupled with the wall surface sweeping nozzles, diffusion and mixing of fuel oil are enhanced, and then the combustion efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of scramjet engines, and in particular to a support plate type supersonic combustion chamber coupled with a wall swept nozzle. Background Art

[0002] Scramjet engines have the characteristics of small mass, simple structure, and high specific impulse when flying at high Mach numbers. They are known as the third revolution in aviation history after propellers and jet propulsion. Under high-speed flight conditions, the air flow speed in the combustion chamber of a scramjet engine can reach kilometers per second, and the residence time of fuel in the combustion chamber is only in the millisecond level, which makes it difficult for fuel mixing and combustion. In order to ensure that the fuel can still be quickly mixed and burned in a short residence time, it is very necessary to improve the mixing efficiency of fuel and air in the supersonic combustion chamber.

[0003] At present, the mainstream combustion stabilization scheme in scramjet combustion chambers mainly includes center support plate combustion stabilization. As a highly efficient and reliable flame stabilizer, the center support plate has been used in various scramjet engine combustion chambers. The support plate can inject fuel in the mainstream center area, effectively increasing the utilization rate of mainstream air; however, the fuel injection range on the center support plate is limited, and the fuel mixing efficiency is still low. Summary of the invention

[0004] The object of the present invention is to provide a support plate type supersonic combustion chamber coupled with a wall swept nozzle to solve the problems existing in the above-mentioned prior art, enhance the diffusion and mixing of the fuel, and thus improve the combustion efficiency.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a support plate type supersonic combustion chamber coupled with a wall-surface swept nozzle, comprising a combustion chamber body, a central support plate and a plurality of sweep nozzles; one end of the combustion chamber body is an air inlet end, and the other end is an air outlet end; the central support plate is fixedly arranged in the combustion chamber body, and a plurality of fuel spray holes for spraying fuel into the combustion chamber body are arranged on the central support plate; a plurality of sweep nozzles are circumferentially arranged on the inner wall of the combustion chamber body, and each of the sweep nozzles is used to sweep and spray fuel into the combustion chamber body.

[0007] Preferably, the central support plate is arranged in the combustion chamber body along the air flow direction, and the front end of the central support plate close to the air inlet end is arranged as a tapered end, and the plurality of fuel injection holes are arranged on both sides of the tapered end.

[0008] Preferably, the plurality of fuel injection holes on both sides of the tapered end are symmetrically arranged.

[0009] Preferably, each of the sweeping nozzles is configured as a self-excited sweeping nozzle.

[0010] Preferably, the combustion chamber body includes an isolation section, an expansion section and an equal straight section which are connected in sequence along the air flow direction, one end of the isolation section is the air inlet end, and one end of the equal straight section is the air outlet end; the central support plate is fixedly arranged on the bottom wall of the isolation section; and the plurality of sweep nozzles are fixedly arranged on the top wall and side wall of the expansion section along the circumferential direction.

[0011] Preferably, one side end of the central support plate facing away from the air inlet end is flush with one side end of the isolation section facing away from the air inlet end.

[0012] Preferably, a plurality of the sweep nozzles are fixedly arranged along the circumferential direction on the inner wall of the side end of the expansion section away from the isolation section, and the sweep nozzles on the opposite side walls of the expansion section are symmetrically arranged.

[0013] Preferably, it further comprises an air inlet and a nozzle respectively connected to the air inlet end and the air outlet end, wherein the air inlet is used for introducing gas and the nozzle is used for exhausting gas.

[0014] Preferably, the cross-sectional size of the air inlet duct gradually decreases along the airflow direction.

[0015] Preferably, the cross-sectional dimension of the nozzle increases along the airflow direction.

[0016] Compared with the prior art, the present invention has achieved the following technical effects:

[0017] The support plate type supersonic combustion chamber coupled with the wall-surface swept nozzle provided by the present invention has a central support plate and a plurality of sweep nozzles arranged in the combustion chamber body, a plurality of fuel nozzle holes are arranged on the central support plate to spray fuel into the combustion chamber body, and the plurality of sweep nozzles arranged circumferentially are used to sweep and spray fuel from the wall surface, thereby increasing the penetration depth of the fuel in the combustion chamber body and improving the mixing efficiency of the fuel, thereby improving the combustion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A front view of a support plate type supersonic combustion chamber coupled with a wall swept nozzle provided in Example 1;

[0020] Figure 2 A top view of a support plate type supersonic combustion chamber coupled with a wall swept nozzle provided in Example 1;

[0021] Figure 3A side view of a support plate type supersonic combustion chamber coupled with a wall swept nozzle provided in Example 1.

[0022] In the figure: 1-support plate type supersonic combustion chamber coupled with swept nozzle; 10-combustion chamber body; 11-isolation section; 12-expansion section; 13-equal straight section; 20-center support plate; 21-conical end; 22-fuel spray hole; 30-swept nozzle; 40-inlet duct; 50-nozzle. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] The object of the present invention is to provide a support plate type supersonic combustion chamber coupled with a wall swept nozzle to solve the problems existing in the above-mentioned prior art, enhance the diffusion and mixing of the fuel, and thus improve the combustion efficiency.

[0025] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Embodiment 1

[0027] This embodiment provides a support plate type supersonic combustion chamber 1 coupled with a swept nozzle, see Figure 1-Figure 3 , including a combustion chamber body 10, a central support plate 20 and a plurality of sweep nozzles 30; one end of the combustion chamber body 10 is an air inlet end, and the other end is an air outlet end; the central support plate 20 is fixedly arranged in the combustion chamber body 10, and a plurality of fuel spray holes 22 for spraying fuel into the combustion chamber body 10 are arranged on the central support plate 20; a plurality of sweep nozzles 30 are circumferentially arranged on the inner wall of the combustion chamber body 10, and each sweep nozzle 30 is used for sweeping and spraying fuel into the combustion chamber body 10.

[0028] A central support plate 20 and a plurality of sweep nozzles 30 are arranged in the combustion chamber body 10. A plurality of fuel spray holes 22 are arranged on the central support plate 20 to spray fuel into the combustion chamber body 10. In conjunction with the plurality of sweep nozzles 30 arranged circumferentially, the fuel is swept and sprayed from the wall surface, thereby increasing the fuel penetration depth in the combustion chamber body 10 and improving the mixing efficiency of the fuel, thereby improving the combustion efficiency.

[0029] The fuel injection holes 22 of the center support plate 20 and the sweep nozzle 30 are connected to an external fuel supply.

[0030] Among the optional solutions of this embodiment, it is more preferred to refer to Figure 2 The center support plate 20 is arranged in the combustion chamber body 10 along the air flow direction, and the front end of the center support plate 20 close to the air intake end is set as a tapered end 21, and a plurality of fuel injection holes 22 are set on both sides of the tapered end 21; by setting the front end as the tapered end 21, the air resistance is reduced, and the fuel injection holes 22 are set on the side of the tapered end 21 to facilitate the mixing of fuel and air.

[0031] In the optional solution of this embodiment, it is more preferred that the multiple fuel injection holes 22 on both sides of the tapered end 21 are symmetrically arranged to ensure uniform mixing on both sides of the center support plate 20.

[0032] In the optional scheme of this embodiment, it is more preferred that the sweeping nozzles 30 are all configured as sweeping nozzles. The structure of the sweeping nozzle adopts the existing self-excited sweeping nozzle for scramjet engines, which has a main cavity and a feedback reflux channel. Reflux bubbles are generated in the main cavity, so that the fluid flows along the inner wall of the main cavity, and is ejected in a certain direction at the outlet of the sweeping nozzle, and oscillates periodically with a frequency of 1000 to 1600 Hz. The reflux channel is located on both sides of the main cavity, connected to the main cavity and at a certain angle. The flow channel width is 0.5 to 1 mm, which can meet the injection requirements under supersonic combustion conditions. Compared with the traditional direct-injection sweeping nozzle on the wall, the sweeping nozzle allows the fuel to have a larger sweeping area, so that the fuel can fill the combustion chamber, and can minimize the number of sweeping nozzles, increase the fuel penetration depth, and enhance the mixing efficiency and atomization performance of the fuel.

[0033] Further preferably, the sweep nozzle fuel sweep angle is 30 to 90°, and the number and distribution position are determined according to the size of the combustion chamber body 10, so that the injection ranges of adjacent sweep nozzles are connected in the circumferential direction to achieve full sweep of the top wall and side walls.

[0034] In the optional scheme of this embodiment, it is more preferred that the combustion chamber body 10 includes an isolation section 11, an expansion section 12 and an equal straight section 13 connected in sequence along the air flow direction, one end of the isolation section 11 is the air inlet end, and one end of the equal straight section 13 is the air outlet end; the central support plate 20 is fixedly arranged on the bottom wall of the isolation section 11; a plurality of sweep nozzles 30 are fixedly arranged on the top wall and side wall of the expansion section 12 along the circumferential direction; wherein, the isolation section 11 is used to resist the non-starting phenomenon induced by the back pressure generated by the combustion in the combustion chamber to ensure the stable operation of the front air inlet 40; the expansion section 12 plays a role in resisting back pressure inside the combustion chamber to ensure a stable combustion process; the equal straight section 13 will generate a thermal throat in the subsonic mode to accelerate the subsonic airflow to the supersonic state; wherein the expansion ratio of the expansion section 12 can be 1.6, that is, the rear end cross-sectional area is 1.6 times the front end cross-sectional area; the specific size of the combustion chamber body 10 can be determined according to actual needs.

[0035] In the optional scheme of this embodiment, it is more preferred that the side end of the central support plate 20 facing away from the air inlet end is flush with the side end of the isolation section 11 facing away from the air inlet end. The central support plate is arranged at the above position on the wall sweep nozzle, which can make the fuel fill the entire combustion chamber, enhance fuel mixing, and improve combustion efficiency.

[0036] In the optional scheme of this embodiment, it is more preferred that a plurality of sweeping nozzles 30 are fixedly arranged along the circumferential direction on the inner wall of the side end of the expansion section 12 away from the isolation section 11, and the sweeping nozzles 30 on the opposite side walls of the expansion section 12 are symmetrically arranged to improve the uniformity of mixing.

[0037] Among the optional schemes of this embodiment, it is more preferred that the support plate type supersonic combustion chamber 1 coupled with the swept nozzle provided in this embodiment also includes an air inlet 40 and a nozzle 50 respectively connected to the air inlet end and the air outlet end. The air inlet 40 is provided to facilitate the introduction of gas, and the nozzle 50 is provided to facilitate the ejection of exhaust gas.

[0038] In the optional solution of this embodiment, it is more preferred that the cross-sectional size of the air inlet duct 40 gradually decreases along the air flow direction.

[0039] In the optional scheme of this embodiment, it is more preferred that the cross-sectional size of the nozzle 50 increases along the airflow direction, wherein the expansion ratio of the nozzle 50 may be 1.3, that is, the cross-sectional area of ​​the rear end is 1.3 times the cross-sectional area of ​​the front end.

[0040] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A strut-type supersonic combustion chamber coupled with a swept nozzle, characterized in that: include: A combustion chamber body (10), wherein one end of the combustion chamber body (10) is an air inlet end and the other end is an air outlet end; A central support plate (20) is fixedly disposed in the combustion chamber body (10), and a plurality of fuel injection holes (22) are disposed on the central support plate (20) for injecting fuel into the combustion chamber body (10); and A plurality of sweep nozzles (30) are circumferentially arranged on the inner wall of the combustion chamber body (10), and each of the sweep nozzles (30) is used for sweeping and spraying fuel into the combustion chamber body (10).

2. The strut-type supersonic combustion chamber coupled with a swept nozzle according to claim 1, characterized in that: The central support plate (20) is arranged in the combustion chamber body (10) along the air flow direction, and the front end of the central support plate (20) close to the air intake end is arranged as a tapered end (21), and a plurality of fuel injection holes (22) are arranged on both sides of the tapered end (21).

3. The strut-type supersonic combustion chamber coupled with a swept nozzle according to claim 2, characterized in that: The plurality of fuel injection holes (22) on both sides of the tapered end (21) are symmetrically arranged.

4. The strut-type supersonic combustion chamber coupled with a swept nozzle according to claim 1, characterized in that: The sweeping nozzles (30) are all configured as sweeping nozzles.

5. The strut-type supersonic combustion chamber coupled with a swept nozzle according to claim 1, characterized in that: The combustion chamber body (10) comprises an isolation section (11), an expansion section (12) and an equal straight section (13) which are connected in sequence along the air flow direction, one end of the isolation section (11) is the air inlet end, and one end of the equal straight section (13) is the air outlet end; the central support plate (20) is fixedly arranged on the bottom wall of the isolation section (11); and a plurality of sweep nozzles (30) are fixedly arranged on the top wall and side wall of the expansion section (12) along the circumferential direction.

6. The strut-type supersonic combustion chamber coupled with a swept nozzle according to claim 5, characterized in that: One side end of the central support plate (20) facing away from the air inlet end is flush with one side end of the isolation section (11) facing away from the air inlet end.

7. The strut-type supersonic combustion chamber coupled with a swept nozzle according to claim 5, characterized in that: A plurality of sweep nozzles (30) are fixedly arranged along the annular direction on the inner wall of the side end of the expansion section (12) away from the isolation section (11), and the sweep nozzles (30) on the opposite side walls of the expansion section (12) are symmetrically arranged.

8. The strut-type supersonic combustion chamber coupled with a swept nozzle according to claim 1, characterized in that: It also includes an air inlet (40) and a nozzle (50) respectively connected to the air inlet end and the air outlet end. The air inlet (40) is used to introduce gas, and the nozzle (50) is used to exhaust gas.

9. The strut-type supersonic combustion chamber coupled with a swept nozzle according to claim 8, characterized in that: The cross-sectional size of the air inlet passage (40) gradually decreases along the airflow direction.

10. The strut-type supersonic combustion chamber coupled with a swept nozzle according to claim 8, characterized in that: The cross-sectional dimension of the nozzle (50) increases along the airflow direction.

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