A hydrogen fuel flow pipe type swirl combustion chamber head

Abstract

The application belongs to the field of aviation power technology, and discloses a hydrogen fuel flow pipe type rotational flow combustion chamber head, which comprises a central rotational flow cup and a primary rotational flow device, and the primary rotational flow device is sleeved on the central rotational flow cup. The primary rotational flow device comprises an outer ring, an inner ring and a spiral half pipe structure, the inner wall of the outer ring and the outer wall of the inner ring surround a hydrogen gas collecting cavity, and a hydrogen injection rod in communication with the hydrogen gas collecting cavity is arranged on the front end of the outer ring along the airflow direction. The spiral half pipe structure comprises a plurality of spiral half pipes, the plurality of spiral half pipes are uniformly arranged on the outer part of the outer ring in the circumferential direction, a first air flow channel is formed between the inner wall of the spiral half pipe and the outer wall of the outer ring, and the outer ring is provided with a hydrogen injection hole corresponding to the outlet of each first air flow channel. The flow pipe type rotational flow combustion chamber head of the application can realize stable hydrogen fuel combustion, improve the mixing quality and spatial distribution uniformity of hydrogen fuel and air, effectively reduce the maximum gas temperature in the combustion zone, and further reduce the NO x emission.

Description

Technical Field

[0001] The invention belongs to the field of aviation power, relates to the design technology of hydrogen fuel gas turbine engines, and in particular to a hydrogen fuel flow tube type swirl combustion chamber head. Background Art

[0002] Currently, there are two main technical paths to reduce carbon emissions in the aviation power sector. One is to make incremental improvements to existing designs to improve fuel efficiency. However, the current average annual fuel efficiency improvement is 2%, making it difficult to achieve true decarbonization goals. The other is transformative development, which involves adopting new energy sources with low carbon emissions and vigorously developing low-carbon / negative-carbon energy to replace traditional aviation kerosene.

[0003] Among the current major carbon emission reduction technologies, hydrogen energy power is the most anticipated aviation carbon neutrality technology approach and the ultimate solution to achieve net zero emissions. Hydrogen energy has the following characteristics: the energy density (calorific value) of liquid hydrogen is 2.78 times that of traditional aviation kerosene; no carbon oxides and smoke are produced during the combustion process, that is, the amount of carbon dioxide released by burning hydrogen is zero, and zero carbon emissions can be achieved; it has high thermal stability and high heat sink, making it an ideal cooling medium for aviation power, which is beneficial to engine thermal management.

[0004] Currently, common hydrogen combustion organization modes include micro-mixed premixed combustion and micro-mixed non-premixed combustion. Among them, micro-mixed premixed combustion refers to the pre-mixing of hydrogen and air in the microchannel, and the mixed gas is ejected through the same nozzle together. The use of premixed combustion can effectively reduce the emission of nitrogen oxides from hydrogen combustion. Under the condition of generating the same heat, the nitrogen oxide generation of hydrogen premixed combustion can be reduced to 1 / 20 of that of aviation kerosene. However, the activity of hydrogen in the premixed reaction and the higher flame speed make the flame front thinner and make it easier for the flame to move upstream, which will increase the risk of flashback. Micro-mixed non-premixed combustion is a new type of combustion mode, also known as diffusion combustion. Hydrogen and air pass through the jet channel at high speed separately, and hydrogen is injected at the air outlet. The two are mixed and burned at the outlet of the microchannel. Compared with premixed combustion, diffusion combustion can avoid the "backfire" problem of hydrogen combustion and improve combustion efficiency and stability. However, diffusion combustion is also accompanied by higher nitrogen oxide emissions. Summary of the Invention

[0005] In order to solve the technical problems of flashback problem in traditional micro-mixed premixed combustion mode and uneven mixing and high nitrogen oxide emissions in micro-mixed non-premixed combustion mode, the present invention discloses a hydrogen fuel flow tube type swirl combustion chamber head, the flow tube type swirl combustion chamber head includes a central swirl cup and a main-stage swirler, and the main-stage swirler is sleeved on the central swirl cup.

[0006] The primary cyclone comprises an outer ring, an inner ring and a spiral half-tube structure. The inner wall of the outer ring and the outer wall of the inner ring form a hydrogen collecting cavity. A hydrogen spray rod connected to the hydrogen collecting cavity is provided at the front end of the outer ring along the airflow direction.

[0007] The spiral half-tube structure includes a plurality of spiral half-tubes, which are uniformly arranged on the outside of the outer ring in a circumferential direction. A first air flow channel is formed between the inner wall of the spiral half-tube and the outer wall of the outer ring. The outer ring is provided with a hydrogen spray hole corresponding to the outlet of each first air flow channel.

[0008] Furthermore, the angle between the outlet of the first air flow channel and the axis of the central swirl cup is 0 to 60 degrees.

[0009] Furthermore, the relationship between the number and radius of the spiral half-tubes and the air flow rate is: Wherein, Wa is the air flow rate input to the first air flow channel, Cd is the air flow coefficient of the spiral half-tube, d is the radius of the spiral half-tube, and n is the number of spiral half-tubes.

[0010] Furthermore, the distance between the hydrogen spray hole and the outlet of the first air flow channel is 1 to 3 mm.

[0011] Furthermore, a U-shaped groove is circumferentially provided at the connection position of the outer ring and the inner ring along the airflow direction, and the height of the tongue at the end of the U-shaped groove along the airflow direction is smaller than the height of the front end of the U-shaped groove along the airflow direction.

[0012] Furthermore, a straight tube is sleeved on the outside of the spiral half-tube structure, and a second air flow channel is formed between the inner wall of the straight tube and the spiral half-tube structure.

[0013] Furthermore, the central swirl cup includes a cyclone, a venturi tube and a central cone. The cyclone is arranged on the periphery of the central cone, and the venturi tube is coaxially sleeved outside the cyclone.

[0014] Furthermore, the swirler includes a plurality of straight blades or curved blades.

[0015] Furthermore, the front dead point of the recirculation zone of the central swirl cup is obtained, and the distance between the downstream end face of the central cone and the throat of the upper expansion and contraction section of the venturi is determined based on the constraint condition that the front dead point of the recirculation zone does not contact the downstream end face of the central cone.

[0016] Compared with the prior art, the beneficial effects achieved by at least one of the above-mentioned technical solutions adopted in the embodiments of this specification include at least the following: the hydrogen fuel flow tube swirl combustion chamber head of the present invention is mainly composed of three parts: a central swirl cup, a primary swirler (including a hydrogen gas collecting chamber, a spiral half-tube structure, and a straight cylinder, etc.), and a hydrogen spray rod. The central swirl cup is composed of a central cone and a swirler and a venturi coaxially surrounding the outer ring; the hydrogen spray rod and the primary swirler can be designed as an integrated whole. The central swirl cup and the primary swirler work together to control the morphology of the recirculation zone; the number of spiral half-tubes in the primary swirler corresponds one-to-one to the number of downstream hydrogen nozzle holes. Each spiral half-tube is paired with each hydrogen nozzle hole, allowing air and hydrogen to mix directly, and semi-premixed or diffusion combustion to occur downstream. This can achieve full and uniform mixing of hydrogen fuel and air before combustion, effectively avoiding hydrogen concentration concentration and the generation of a chemically appropriate combustion zone, thereby reducing the formation of local hot spots during combustion and further reducing nitrogen oxide emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 A cross-sectional view of the head of a hydrogen fuel flow tube type swirl combustion chamber disclosed in an embodiment of the present invention;

[0019] Figure 2 A perspective view of the head of a hydrogen fuel flow tube swirl combustion chamber disclosed in an embodiment of the present invention;

[0020] Among them, 1. Outer ring; 2. Inner ring; 10. U-shaped groove; 11. Swirl; 12. Venturi tube; 13. Center cone; 14. Spiral half tube; 15. Hydrogen spray hole; 16. Hydrogen gas collecting chamber; 17. Straight cylinder; 18. Tongue; 19. Hydrogen spray rod. DETAILED DESCRIPTION

[0021] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0022] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features of the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0023] In the description of this embodiment, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the invention.

[0024] Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, features qualified as "first," "second," etc., may explicitly or implicitly include one or more features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0025] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present disclosure. The illustrations only show components related to the present disclosure and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0026] An embodiment of the present invention discloses a hydrogen fuel flow tube type swirl combustion chamber head. The flow tube type swirl combustion chamber head comprises a central swirl cup and a primary swirler. The primary swirler is sleeved on the central swirl cup.

[0027] Among them, see Figure 1 and Figure 2As shown, the primary cyclone includes an outer ring 1, an inner ring 2 and a spiral half-tube structure. The inner wall of the outer ring 1 and the outer wall of the inner ring 2 form a hydrogen collecting cavity 16. A hydrogen spray rod 19 is provided on the front end of the outer ring 1 along the airflow direction and is connected to the hydrogen collecting cavity 16.

[0028] The spiral half-tube structure includes multiple spiral half-tubes 14, which are evenly arranged on the outside of the outer ring 1 in a circumferential direction. A first air flow channel is formed between the inner wall of the spiral half-tube 14 and the outer wall of the outer ring 1. The outer ring 1 is provided with a hydrogen spray hole 15 corresponding to the outlet of each first air flow channel.

[0029] In specific implementation, each spiral half-tube 14 is paired with each hydrogen nozzle 15, so that air and hydrogen can be directly mixed and semi-premixed or diffused combustion is carried out downstream, which can achieve full and uniform mixing of hydrogen fuel and air before combustion, effectively avoiding the concentration of hydrogen concentration and the generation of chemically appropriate combustion zones, thereby reducing the formation of local hot spots during the combustion process and further reducing nitrogen oxide emissions. While achieving combustion stability in the hydrogen fuel combustion chamber, the present invention improves the mixing quality and spatial distribution uniformity of hydrogen fuel and air, effectively reduces the maximum gas temperature in the combustion zone, and thus reduces NO x emissions.

[0030] Further, see Figure 2 As shown, the angle between the outlet of the first air flow channel and the axis of the central swirl cup is 0-60°. In specific implementation, the angle can be determined according to the swirl intensity of the airflow.

[0031] Furthermore, the relationship between the number and radius of the spiral half-tubes 14 and the air flow rate is: Wherein, Wa is the air flow rate input to the first air flow channel, Cd is the air flow coefficient of the spiral half-tube, d is the radius of the spiral half-tube, and n is the number of spiral half-tubes.

[0032] Furthermore, the distance between the hydrogen spray hole 15 and the outlet of the first air flow channel is 1 to 3 mm.

[0033] Further, see Figure 1 and Figure 2 As shown, a U-shaped groove 10 is circumferentially provided at the connection position of the outer ring 1 and the inner ring 2 along the end of the airflow direction, and the height of the tongue 18 at the end of the U-shaped groove 10 along the airflow direction is smaller than the height of the front end of the U-shaped groove 10 along the airflow direction.

[0034] Further, see Figure 1 and Figure 2 As shown, a straight tube 17 is sleeved on the outside of the spiral half-tube structure, and a second air flow channel is formed between the inner wall of the straight tube 17 and the spiral half-tube structure.

[0035] Furthermore, the central swirl cup achieves stable combustion of the hydrogen fuel flame, and the main stage achieves full and uniform mixing of hydrogen fuel with air before combustion, effectively avoiding concentration of hydrogen and the formation of chemically appropriate combustion zones, thereby reducing the formation of local hot spots during the combustion process and further reducing nitrogen oxide emissions. Figure 1 As shown, the central swirl cup includes a cyclone 11, a venturi 12, and a central cone 13. The cyclone 11 is disposed on the periphery of the central cone 13, and the venturi 12 is coaxially sleeved outside the cyclone 11. Specifically, the central swirl cup comprises one or more stages of axial or radial cyclones and converging / diverging sections. The center of the cyclone is the central cone 13, and the blades of the cyclone 11 are grown on the surface of the central cone.

[0036] Furthermore, the swirler 11 includes a plurality of straight blades or curved blades.

[0037] Furthermore, the front dead point of the recirculation zone of the central swirl cup is obtained, and based on the constraint condition that the front dead point of the recirculation zone does not contact the downstream end face of the central cone 13, the distance between the downstream end face of the central cone 13 and the throat of the expansion and contraction section of the venturi tube 12 is determined. The setting of the throat of the expansion and contraction section of the venturi tube 12 can prevent the "backfire" problem of hydrogen combustion.

[0038] The hydrogen fuel flow tube type swirl combustion chamber head of the present invention is mainly composed of three parts: a central swirl cup, a main-stage swirler (including a hydrogen gas collecting chamber, a spiral half-tube structure, and a straight cylinder, etc.) and a hydrogen spray rod. The central swirl cup is composed of a central cone and a swirler and a venturi coaxially surrounding the outer ring; the hydrogen spray rod and the main-stage swirler can be designed in an integrated manner. The morphology of the recirculation zone is controlled by the joint action of the central swirl cup and the main-stage swirler; the number of spiral half-tubes of the main-stage swirler corresponds one-to-one to the number of downstream hydrogen nozzles. Each spiral half-tube is paired with each hydrogen nozzle, so that air and hydrogen are directly mixed, and semi-premixed or diffusion combustion is carried out downstream, which can achieve full and uniform mixing of hydrogen fuel and air before combustion, effectively avoiding the concentration of hydrogen concentration and the generation of a chemically appropriate ratio combustion zone, thereby reducing the formation of local hot spots during the combustion process, and further reducing the emission of nitrogen oxides.

[0039] Obviously, those skilled in the art will understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations are possible in the embodiments of the present invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

[0040] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A hydrogen fuel flow tube swirl combustion chamber head, comprising a central swirl cup and a primary swirler, wherein the primary swirler is sleeved on the central swirl cup, characterized in that: The primary cyclone comprises an outer ring (1), an inner ring (2) and a spiral half-tube structure, wherein the inner wall of the outer ring (1) and the outer wall of the inner ring (2) form a hydrogen gas collecting cavity (16), and a hydrogen spray rod (19) is provided at the front end of the outer ring (1) along the airflow direction and communicates with the hydrogen gas collecting cavity (16); The spiral half-tube structure comprises a plurality of spiral half-tubes (14), wherein the plurality of spiral half-tubes (14) are uniformly arranged on the outside of the outer ring (1) in a circumferential direction, a first air flow channel is formed between the inner wall of the spiral half-tube (14) and the outer wall of the outer ring (1), and the outer ring (1) is provided with a hydrogen spray hole (15) corresponding to the outlet of each first air flow channel; A straight cylinder (17) is sleeved on the outside of the spiral half-tube structure, and a second air flow channel is formed between the inner wall of the straight cylinder (17) and the spiral half-tube structure.

2. The hydrogen fuel flow tube type swirl combustion chamber head according to claim 1, characterized in that: The angle between the outlet of the first air flow channel and the axis of the central swirl cup is 0-60°.

3. The hydrogen fuel flow tube type swirl combustion chamber head according to claim 1, characterized in that: The relationship between the number and radius of the spiral half-tubes (14) and the air flow rate is: , where Wa is the air flow rate input to the first air flow channel, Cd is the spiral half-tube air flow coefficient, d is the spiral half-tube radius, and n is the number of spiral half-tubes.

4. The hydrogen fuel flow tube type swirl combustion chamber head according to claim 1, characterized in that: The distance between the hydrogen spray hole (15) and the outlet of the first air flow channel is 1-3 mm.

5. The hydrogen fuel flow tube type swirl combustion chamber head according to claim 1, characterized in that: A U-shaped groove (10) is circumferentially provided at the connection position of the outer ring (1) and the inner ring (2) at the end in the airflow direction, and the height of the tongue piece (18) at the end in the airflow direction of the U-shaped groove (10) is smaller than the height of the front end in the airflow direction of the U-shaped groove (10).

6. The hydrogen fuel flow tube type swirl combustion chamber head according to claim 1, characterized in that: The central swirl cup comprises a cyclone (11), a venturi tube (12) and a central cone (13); the cyclone (11) is arranged on the periphery of the central cone (13); and the venturi tube (12) is coaxially sleeved outside the cyclone (11).

7. The hydrogen fuel flow tube type swirl combustion chamber head according to claim 6, characterized in that: The swirler (11) comprises a plurality of straight blades or curved blades.

8. The hydrogen fuel flow tube type swirl combustion chamber head according to claim 6, characterized in that: The front dead point of the recirculation zone of the central swirl cup is obtained, and the distance between the downstream end face of the central cone (13) and the throat of the upper expansion and contraction section of the venturi tube (12) is determined based on the constraint condition that the front dead point of the recirculation zone does not contact the downstream end face of the central cone (13).

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