Composite nozzle for oxygen hydrocarbon fuel torch igniter

Abstract

The invention provides a composite nozzle for an oxygen hydrocarbon fuel torch igniter. The composite nozzle is suitable for oxygen-liquid hydrocarbon fuel and oxygen-gaseous hydrocarbon fuel. The composite nozzle mainly comprises a hydrocarbon fuel top cover, a hollow hydrocarbon fuel nozzle, an oxygen injection body, a hydrocarbon fuel annular cavity, an oxygen annular cavity, a cooling medium annular cavity, an annular oxygen channel, a cooling medium injection hole and the like which are coaxially arranged. By reasonably distributing oxygen, hydrocarbon fuel and cooling medium parameters, the wall face of the combustion chamber can be effectively cooled on the premise that high combustion efficiency is guaranteed, and long-time normal work and service life of the igniter are guaranteed.

Description

Technical Field

[0001] The present invention relates to a nozzle for an oxygen hydrocarbon fuel torch igniter, and in particular to a torch igniter nozzle that takes into account both atomization mixing and torch igniter combustion chamber wall cooling. The nozzle can be used as an oxygen hydrocarbon fuel torch igniter component, and can also be applied to torch igniter components of other gas-liquid propellants. Background Art

[0002] Domestic large-scale active ejection high-altitude simulation test benches mostly use rocket steam generators based on liquid rocket engine thrust chamber combustion organization technology with liquid oxygen alcohol (isopropanol) water as propellant to supply steam, and ignition mainly uses torch igniters with oxygen-alcohol propellants. Due to the short working time, the wall of the torch igniter combustion chamber is generally not actively cooled, relying on materials such as stainless steel to directly resist the ablation and erosion of the fuel gas. After multiple ignitions, the inner wall of the torch igniter combustion chamber has a serious ablation or erosion effect, and local overheating and other phenomena occur, causing the life of the torch igniter combustion chamber to be greatly shortened, and even the wall burns through, causing the need for regular replacement, increasing the use cost of the torch igniter. CN201010603619.3 proposes a gas oxygen alcohol torch igniter solution using combustion chamber regenerative cooling. Although it can solve the problem of thermal protection of the combustion chamber wall, it increases the alcohol flow resistance and increases the requirements and cost of the alcohol supply system. How to balance the thermal protection effect and implementation cost of the torch igniter combustion chamber is an important aspect of torch igniter design. Summary of the invention

[0003] Problems solved by the invention: Solve the problem of ablation and erosion of the inner wall surface by the gas in the combustion chamber of the torch igniter, improve the thermal environment of the inner wall surface of the combustion chamber of the torch igniter, extend the service life of the combustion chamber of the torch igniter without significantly increasing the cost, and improve the operating reliability of the torch igniter.

[0004] The solution of the invention is as follows: hydrocarbon fuel injection, oxygen injection, and hydrocarbon fuel injection are arranged in sequence from the center line of the nozzle to the edge of the nozzle. The hydrocarbon fuel injection near the center line adopts direct current or centrifugal injection, and forms a coaxial centrifugal or direct current injection combination with the oxygen injection to enhance the oxygen-fuel mixing. The hydrocarbon fuel or inert gas at the edge of the nozzle is injected in a direct current injection manner and at a certain angle to inject part of the hydrocarbon fuel or inert gas onto the inner wall surface of the combustion chamber to form a liquid film to achieve an internal cooling effect.

[0005] Advantages of the invention: By reasonably allocating the flow rate and injection angle of the cooling medium or inert gas used to cool the combustion chamber wall, a liquid film / gas film can be formed to effectively cool the combustion chamber wall, and the oxygen / hydrocarbon fuel combustion mixture ratio near the axis of the combustion chamber can be close to the chemically appropriate ratio, with high combustion efficiency; the liquid film / gas film flow and heat insulation near the combustion chamber wall can effectively cool the wall, ensuring the normal operation and service life of the igniter for a long time.

[0006] The present invention is further described below with reference to the accompanying drawings and typical examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 Schematic diagram of the composite nozzle structure for the oxygen hydrocarbon fuel torch igniter proposed by the present invention

[0008] Figure 2 Schematic diagram of the structure of a torch igniter using a composite nozzle

[0009] The reference numerals in the figure are: 1-hydrocarbon fuel top cover, 2-hollow hydrocarbon fuel nozzle, 3-oxygen injection body, 4-hydrocarbon fuel annular cavity, 5-oxygen annular cavity, 6-hole-shaped channel connecting the oxygen annular cavity 5 and the annular oxygen channel 10, 7-cooling medium annular cavity, 8-cooling medium injection hole, 9-hole-shaped channel connecting the hydrocarbon fuel annular cavity 4 and the hollow hydrocarbon fuel nozzle 2, 10-annular oxygen channel, 11-exit end face of the hollow hydrocarbon fuel nozzle 2, 12-exit end face of the oxygen injection body 3, 13-torch igniter combustion chamber, 14-electric ignition device DETAILED DESCRIPTION

[0010] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0011] Depend on Figure 1 It can be seen that the composite nozzle for the oxygen hydrocarbon fuel torch igniter of the present invention mainly comprises a coaxially arranged hydrocarbon fuel top cover 1, a hollow hydrocarbon fuel nozzle 2, and an oxygen injector 3; the hydrocarbon fuel top cover 1 is located at the top of the oxygen injector 3, and a hydrocarbon fuel annular cavity 4 is formed between the hollow hydrocarbon fuel nozzle 2 and the oxygen injector 3; an oxygen annular cavity 5 and a cooling medium annular cavity 7 are arranged inside the oxygen injector 3; the hydrocarbon fuel annular cavity 4, the oxygen annular cavity 5, and the cooling medium annular cavity 7 are independent of each other; an annular oxygen channel 10 is formed between the hydrocarbon fuel nozzle 2 and the oxygen injector 3; A hydrocarbon fuel inlet is provided on the fuel top cover 1, and the hydrocarbon fuel inlet is connected to the hydrocarbon fuel annular cavity 4; an oxygen inlet is provided on the oxygen injector 3, and the oxygen inlet is connected to the oxygen annular cavity 5; a cooling medium inlet is provided on the oxygen injector 3, and the cooling medium inlet is connected to the cooling medium annular cavity 7; a penetrating cooling medium injection hole 8 is provided between the cooling medium annular cavity 7 and the outlet surface 12 of the oxygen injector 3; the oxygen annular cavity 5 is connected to the annular oxygen channel 10 through a hole-shaped channel 6; the hollow hydrocarbon fuel nozzle 2 is connected to the hydrocarbon fuel annular cavity 4 through a hole-shaped channel 9.

[0012] Embodiment 1: The hydrocarbon fuel is liquid alcohol, the cooling medium is water, the axis of the hole-shaped channel 9 is parallel to the tangential plane of the surface of the hollow hydrocarbon fuel nozzle 2, the axis of the cooling medium injection hole 8 is parallel to the meridian plane of the oxygen injection body 3 and points to the outer surface of the oxygen injection body, and the axis of the hole-shaped channel 6 is perpendicular to the tangential plane of the outer surface of the oxygen injection body 3.

[0013] Liquid alcohol enters the hydrocarbon fuel annular cavity 4 from the hydrocarbon fuel inlet of the hydrocarbon fuel top cover 1, and then enters the interior of the hollow hydrocarbon fuel nozzle 2 through the hole-shaped channel 9. Since the axis of the hole-shaped channel 9 is parallel to the tangent plane of the surface of the hollow hydrocarbon fuel nozzle 2, the hollow hydrocarbon fuel nozzle 2 is a centrifugal nozzle, so that the liquid alcohol is sprayed out from the outlet of the hollow hydrocarbon fuel nozzle 2 in a swirl manner to achieve the first atomization.

[0014] Oxygen enters the oxygen annular cavity 5 from the oxygen inlet of the oxygen injector 3, and then enters the annular oxygen channel 10 through the hole-shaped channel 6, flows along the annular oxygen channel 10 in an axial motion, and mixes with the alcohol after the first atomization downstream of the outlet end face 11 of the hydrocarbon fuel nozzle, and undergoes a second atomization and premixing. A well-atomized and evenly mixed oxygen-alcohol mixture is formed in the torch igniter combustion chamber 13 downstream of the outlet end face 12 of the oxygen injector 3, which is ignited by the electric ignition device 14 and burns stably.

[0015] The cooling medium water enters the cooling medium annular cavity 7 from the cooling medium inlet of the oxygen injector 3, and is then ejected through the cooling medium injection hole 8, injected onto the inner surface of the torch igniter combustion chamber 13 and flows downstream along the inner surface in the form of a liquid film. The length of the liquid film can continue to the outlet cross section of the torch igniter combustion chamber 13. The flow rate of the cooling medium water is determined by a thermal ignition test.

[0016] Embodiment 2: The hydrocarbon fuel is gaseous methane, the cooling medium is nitrogen, the axis of the hole-shaped channel 9 is perpendicular to the tangential plane of the surface of the hollow hydrocarbon fuel nozzle 2, the axis of the cooling medium injection hole 8 is parallel to the tangential plane of the outer surface of the oxygen injection body 3, and the axis of the hole-shaped channel 6 is perpendicular to the tangential plane of the outer surface of the oxygen injection body 3.

[0017] Gaseous methane enters the hydrocarbon fuel annular cavity 4 from the hydrocarbon fuel inlet of the hydrocarbon fuel cap 1, and then enters the interior of the hollow hydrocarbon fuel nozzle 2 through the hole-shaped channel 9. Since the axis of the hole-shaped channel 9 is perpendicular to the tangent plane of the surface of the hollow hydrocarbon fuel nozzle 2, the hollow hydrocarbon fuel nozzle 2 is a direct current nozzle, so that the gaseous methane is ejected and diffused from the outlet of the hollow hydrocarbon fuel nozzle 2 in a direct current manner.

[0018] Oxygen enters the oxygen annular cavity 5 from the oxygen inlet of the oxygen injector 3, and then enters the annular oxygen channel 10 through the hole-shaped channel 6, flows along the annular oxygen channel 10 in an axial motion, and mixes with gaseous methane downstream of the outlet end face 11 of the hydrocarbon fuel nozzle. A uniformly mixed oxygen-methane mixture is formed downstream of the outlet end face 12 of the oxygen injector 3, which is ignited by the electric ignition device 14 and burns stably.

[0019] The cooling medium nitrogen enters the cooling medium annular cavity 7 from the cooling medium inlet of the oxygen injector 3, and is then ejected through the cooling medium injection hole 8, injected onto the inner surface of the torch igniter combustion chamber 13 and flows downstream along the circumference of the inner surface in the form of an air film. The length of the air film can last to the outlet cross section of the torch igniter combustion chamber 13. The flow rate of the cooling medium nitrogen is determined by a thermal ignition test.

[0020] The above is an explanation of the preferred embodiment of the present invention, but the present invention is not limited to the above embodiment. For those skilled in the art, it is obvious that various changes or modifications can be imagined within the scope of the claims, which of course also belong to the technical scope of the present invention.

Claims

1. A composite nozzle for an oxygen hydrocarbon fuel torch igniter, characterized in that; The invention comprises a hydrocarbon fuel cover (1), a hollow hydrocarbon fuel nozzle (2), and an oxygen injector (3) which are coaxially arranged; the hydrocarbon fuel cover (1) is located at the top of the oxygen injector (3), and a hydrocarbon fuel annular cavity (4) is formed between the hydrocarbon fuel cover (1), the hollow hydrocarbon fuel nozzle (2), and the oxygen injector (3); an oxygen annular cavity (5) and a cooling medium annular cavity (7) are provided inside the oxygen injector (3); the hydrocarbon fuel annular cavity (4), the oxygen annular cavity (5), and the cooling medium annular cavity (7) are independent of each other; an annular oxygen channel (10) is formed between the hydrocarbon fuel nozzle (2) and the oxygen injector (3); a hydrocarbon fuel inlet is provided on the hydrocarbon fuel cover (1). The hydrocarbon fuel inlet is connected to the hydrocarbon fuel annular cavity (4); the oxygen injector (3) is provided with an oxygen inlet, which is connected to the oxygen annular cavity (5); the oxygen injector (3) is provided with a cooling medium inlet, which is connected to the cooling medium annular cavity (7); a cooling medium injection hole (8) is provided between the cooling medium annular cavity (7) and the outlet surface (12) of the oxygen injector (3); the oxygen annular cavity (5) is connected to the annular oxygen channel (10) through a hole-shaped channel (6); the hollow hydrocarbon fuel nozzle (2) is connected to the hydrocarbon fuel annular cavity (4) through a hole-shaped channel (9).

2. The composite nozzle for an oxygen hydrocarbon fuel torch igniter according to claim 1, characterized in that The outlet end surface (11) of the hollow hydrocarbon fuel nozzle (2) is located upstream of the outlet end surface (12) of the oxygen injection body (3).

3. The composite nozzle for an oxygen hydrocarbon fuel torch igniter according to claim 1, characterized in that The axis of the hole-shaped passage (6) and the meridian plane of the annular oxygen passage (10) are perpendicular or parallel to each other.

4. The composite nozzle for an oxygen hydrocarbon fuel torch igniter according to claim 1, characterized in that The axis of the hole-shaped passage (9) is perpendicular or parallel to the meridian plane of the hollow hydrocarbon fuel nozzle (2).

5. The composite nozzle for oxygen hydrocarbon fuel torch igniter according to claim 1, characterized in that the cooling The axis of the medium injection hole (8) and the meridian plane of the oxygen injection body (3) are perpendicular or parallel to each other.

6. The composite nozzle for an oxygen hydrocarbon fuel torch igniter according to claim 1, characterized in that The hydrocarbon fuel top cover (1), the hollow hydrocarbon fuel nozzle (2), and the oxygen injection body (3) are welded and connected to each other.

Images