Umbrella-shaped coaxial three-area micro-hydrogen-mixing fuel combustion chamber head

By adopting the head of the umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber in the hydrogen gas turbine, the micro-mixed structure and the three-zone annular chamber return vortex can achieve uniform mixing of hydrogen fuel and air, solving the problems of hydrogen gas turbine backfire and high NOx emissions, significantly reducing NOx emissions.

CN119802672AActive Publication Date: 2025-04-11AECC SICHUAN GAS TURBINE RES INST
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Patent Information

Application Number
CN202510049243.2
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2025-01-13
Publication Date
2025-04-11
Estimated Expiration
2045-01-13

AI Technical Summary

Technical Problem

Existing hydrogen gas turbines have problems of tempering and high NOx emissions, which are difficult to effectively prevent hydrogen combustion backfire and reduce nitrogen oxide emissions.

Method used

The head of the umbrella-shaped coaxial three-zone micro-hydrogen mixed fuel combustion chamber is adopted, including the head cap cover, hydrogen supply rod, central umbrella stabilizer, shunt ring and umbrella-shaped ring stabilizer. Through the micro-mixed structure composed of the inner ring grid, the middle ring grid and the outer ring grid, and the unique three-zone ring cavity return vortex, the hydrogen fuel and air are fully and uniformly mixed.

Benefits of technology

Effectively avoid the formation of hydrogen combustion tempering, concentration of hydrogen concentration and appropriate chemical ratio combustion zones, reduce local hot spots during combustion, and thus significantly reduce NOx emissions.

✦ Generated by Eureka AI based on patent content.

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Abstract

The invention belongs to the technical field of hydrogen fuel gas turbine engines, and discloses an umbrella-shaped coaxial three-area micro-hydrogen-mixing fuel combustion chamber head which comprises a head cap hood, a hydrogen supply rod, a center umbrella-shaped stabilizer, a flow dividing ring and an umbrella-shaped annular stabilizer, the center umbrella-shaped stabilizer, the flow dividing ring and the umbrella-shaped annular stabilizer are coaxially arranged, a circular air inlet hole is formed in the head cap hood, and the hydrogen supply rod is communicated with an inner cavity of the stabilizer. And the stabilizer is provided with a hydrogen injection hole communicated with the inner cavity. An inner annular grid is arranged between the center umbrella-shaped stabilizer and the flow dividing ring, a middle annular grid is arranged between the flow dividing ring and the umbrella-shaped annular stabilizer, and an outer annular grid is arranged between the umbrella-shaped annular stabilizer and the inner circumferential wall of the head cap hood. A unique three-area annular cavity backflow vortex can be formed on the head portion of the combustion chamber, hydrogen fuel can be fully and evenly mixed with air in the whole combustion area before combustion, hydrogen combustion tempering, hydrogen concentration concentration and generation of a chemical proper ratio combustion area are effectively avoided, and therefore local hot spots formed in the combustion process are reduced, and NOx emission is reduced.
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Description

Technical Field

[0001] The invention belongs to the technical field of hydrogen fuel gas turbine engines and relates to an umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber head. Background Art

[0002] In recent years, the world's major economies have proposed carbon neutrality climate goals. The main measures to achieve carbon neutrality include emission reduction and carbon sink enhancement. Among them, the most promising direction is the clean and low-carbon energy structure. The fundamental measure is to achieve clean energy production and electrification of energy consumption. Clean energy and renewable energy have become the main direction of energy development.

[0003] As a clean and sustainable energy carrier, hydrogen has attracted people's attention and is regarded as a powerful driving force for achieving carbon neutrality. Hydrogen has accelerated the increase in the proportion of renewable energy in the energy structure and has been considered the most promising solution for large-scale long-term seasonal carbon-free energy storage. From the current perspective, hydrogen gas turbines have the advantages of zero carbon emissions, flexibility and controllability, and are about to become an important mainstay of the new power grid, but their flashback and NO x Problems such as high emissions still hinder the widespread use of hydrogen gas turbines.

[0004] Currently, micro-mixing combustors are considered to prevent flashback and reduce NO in hydrogen gas turbines. x The most realistic and feasible method for emissions, but there is still flashback and NO x High emissions, etc. Summary of the invention

[0005] In order to solve the technical problems of flashback and high nitrogen oxide emissions in existing hydrogen gas turbines, the present invention discloses a coaxial three-zone micro-mixed hydrogen fuel combustion chamber head, the combustion chamber head includes a head cap, a hydrogen supply rod, and a central umbrella-shaped stabilizer, a diverter ring and an umbrella-shaped annular stabilizer coaxially arranged outward along the central axis, and a circular air inlet hole is opened in the center of the head cap.

[0006] The hydrogen supply nozzles of the hydrogen supply rod extend into the inner cavities of the central umbrella-shaped stabilizer and the umbrella-shaped annular stabilizer respectively, and the central umbrella-shaped stabilizer and the umbrella-shaped annular stabilizer are both provided with hydrogen injection holes connected with the inner cavities.

[0007] An inner annular grid is provided between the central umbrella-shaped stabilizer and the diverter ring, an intermediate annular grid is provided between the diverter ring and the umbrella-shaped annular stabilizer, and an outer annular grid is provided between the umbrella-shaped annular stabilizer and the inner peripheral wall of the head cap.

[0008] Furthermore, the central umbrella-shaped stabilizer and the umbrella-shaped annular stabilizer both include a streamlined leading edge surface, a conical outer surface and a rear end surface, and the conical outer surface is evenly provided with a plurality of hydrogen injection holes connected to the inner cavity along the circumferential direction.

[0009] Furthermore, the hydrogen injection hole is an inclined hole opened along the air flow direction.

[0010] Furthermore, the rear end surfaces of the central umbrella-shaped stabilizer and the umbrella-shaped annular stabilizer are coated with a refractory coating.

[0011] Furthermore, the rear end face includes a middle cylindrical surface and an outer annular surface, and the area surrounded by the middle cylindrical surface of the central umbrella-shaped stabilizer, the outer annular surface and the refractory ring at the rear end of the diverter ring forms an inner annular cavity reflux vortex, the area surrounded by the middle cylindrical surface of the umbrella-shaped annular stabilizer, the outer annular surface and the refractory ring at the rear end of the diverter ring forms an intermediate annular cavity reflux vortex, and the area surrounded by the middle cylindrical surface of the umbrella-shaped annular stabilizer, the outer annular surface and the outer annular grid form an outer annular cavity reflux vortex.

[0012] Furthermore, the inner ring grille, the middle ring grille and the outer ring grille each include a plurality of grille blades distributed along the circumferential direction, and a grille channel is formed between two adjacent grille blades.

[0013] Furthermore, the distances between two adjacent grille blades in the inner ring grille, the middle ring grille and the outer ring grille are all the same.

[0014] Furthermore, the inner ring grille, the middle ring grille and the outer ring grille are on the same horizontal plane.

[0015] Furthermore, the inner annular grid is fixed on the inner peripheral wall of the diverter ring, and the middle annular grid is fixed on the outer peripheral wall of the diverter ring.

[0016] Compared with the prior art, the beneficial effects that can be achieved by at least one of the above-mentioned technical solutions adopted in the embodiments of this specification include at least the following: the combustion chamber head of the present invention adopts a hydrogen combustion mode of high-speed jet-annular discrete hydrogen cross-flow micro-premixing in a convergent annular channel, the nozzle adopts a main and auxiliary two-stage hydrogen supply nozzle, and the micro-premixed combustion adopts a micro-mixing structure composed of an inner annular channel grid, an intermediate annular channel grid and an outer annular channel grid, and a unique three-zone annular cavity recirculation vortex composed of an umbrella stabilizer, a diverter ring and an umbrella-shaped annular stabilizer, etc., which can achieve full and uniform mixing of hydrogen fuel with air in the entire combustion zone before combustion, effectively avoiding hydrogen combustion backfire, hydrogen concentration concentration and the production of a chemically appropriate ratio combustion zone, thereby reducing the formation of local hot spots during the combustion process, and further reducing NOx emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, 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 application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a cross-sectional view of the head of an umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber disclosed in an embodiment of the present invention;

[0019] Figure 2 A schematic diagram of a flow field formed by a central umbrella-shaped stabilizer and a refractory ring at the rear end of a diverter ring disclosed in an embodiment of the present invention;

[0020] Figure 3 It is a schematic diagram of the flow field formed by the umbrella-shaped annular stabilizer disclosed in an embodiment of the present invention, the refractory ring at the rear end of the diverter ring, and the inner peripheral wall of the head cap;

[0021] Figure 4 It is a schematic diagram of an inner ring grille, a middle ring grille and an outer ring grille disclosed in an embodiment of the present invention;

[0022] Among them, 11, auxiliary hydrogen supply nozzle; 12, central umbrella-shaped stabilizer; 120, inner cavity; 13, inner annular grille; 14, diverter ring; 15, intermediate annular grille; 16, umbrella-shaped annular stabilizer; 17, main hydrogen supply nozzle; 18, outer annular grille; 19, head cap; 191, circular air inlet; 20, central axis; 21, auxiliary hydrogen injection hole; 22, refractory coating; 23, grille blades; 24, grille channel; 25, refractory ring; 26, inner annular cavity recirculation vortex; 27, inner oblique injection hole; 28, outer oblique injection hole; 29, intermediate annular cavity recirculation vortex; 30, outer annular cavity recirculation vortex; 121, streamlined leading edge surface; 122, conical outer surface; 123, rear end surface. DETAILED DESCRIPTION

[0023] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0024] The following describes the implementation methods of the present application through specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the content 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 implementation methods, 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 the following embodiments and the features of the embodiments can be combined with each other in the absence of conflict. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0025] 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" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the invention.

[0026] In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more features. In the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0027] 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 rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0028] The embodiment of the present invention discloses a coaxial three-zone micro-mixed hydrogen fuel combustion chamber head, see Figure 1 , Figure 2 and Figure 3 As shown, the combustion chamber head includes a head cap 19, a hydrogen supply rod, and a central umbrella-shaped stabilizer 12, a diverter ring 14 and an umbrella-shaped annular stabilizer 16 coaxially arranged outward along the central axis 20. A circular air inlet hole 191 is opened in the center of the head cap 19.

[0029] Among them, see Figure 1As shown, the hydrogen supply nozzles of the hydrogen supply rod extend into the inner cavities 120 of the central umbrella-shaped stabilizer 12 and the umbrella-shaped annular stabilizer 16, respectively. The central umbrella-shaped stabilizer 12 and the umbrella-shaped annular stabilizer 16 are both provided with hydrogen injection holes connected to the inner cavities 120. An inner annular grid 13 is provided between the central umbrella-shaped stabilizer 12 and the diverter ring 14, an intermediate annular grid 15 is provided between the diverter ring 14 and the umbrella-shaped annular stabilizer 16, and an outer annular grid 18 is provided between the umbrella-shaped annular stabilizer 16 and the inner peripheral wall of the head cap 19.

[0030] See also Figure 1 As shown, the hydrogen supply nozzle of the hydrogen supply rod includes an auxiliary hydrogen supply nozzle 11 and a main hydrogen supply nozzle 17. The auxiliary hydrogen supply nozzle 11 and the central umbrella-shaped stabilizer 12 are located at the center of the combustion chamber head. The auxiliary hydrogen supply nozzle 11 extends from the center of the left side of the central umbrella-shaped stabilizer 12 and is in the inner cavity 120 of the central umbrella-shaped stabilizer 12, and is sealed at the connection. The inner annular grid 13 is welded to the periphery of the central umbrella-shaped stabilizer 12, the diverter ring 14 is coaxially sleeved on the outside of the inner annular grid 13, the middle annular grid 15 is installed on the periphery of the diverter ring 14 and embedded in the umbrella-shaped annular stabilizer 16, and the axial position of the left and right end faces of the middle annular grid 15 is kept flush with the inner annular grid 13. The main hydrogen supply nozzle 17 extends from the left end of the umbrella-shaped annular stabilizer 16 and is connected and sealed to the umbrella-shaped annular stabilizer 16. The outer annular grid 18 is arranged on the periphery of the umbrella-shaped annular stabilizer 16, and the head cap 19 is an integral arc structure with a circular air inlet hole in the center, which is installed on the outer surface of the outer annular grid 18.

[0031] Further, see Figure 1 As shown, the central umbrella-shaped stabilizer 12 and the umbrella-shaped annular stabilizer 16 both include a streamlined leading edge surface 121 , a conical outer surface 122 and a rear end surface 123 , and a plurality of hydrogen injection holes connected to the inner cavity 120 are uniformly opened on the conical outer surface 122 along the circumferential direction.

[0032] Furthermore, the hydrogen injection hole is an inclined hole opened along the air flow direction, see Figure 1 As shown, the hydrogen injection holes on the central umbrella-shaped stabilizer 12 are auxiliary hydrogen injection holes 21 , and the hydrogen injection holes on the umbrella-shaped annular stabilizer 16 include inner oblique injection holes 27 with outlets toward the middle annular grid 15 and outer oblique injection holes 28 with outlets toward the outer annular grid 18 .

[0033] Furthermore, the rear end surfaces 123 of the central umbrella-shaped stabilizer 12 and the umbrella-shaped annular stabilizer 16 are coated with a refractory coating 22 .

[0034] Further, see Figure 2 and Figure 3As shown, the rear end faces 123 of the central umbrella-shaped stabilizer 12 and the umbrella-shaped annular stabilizer 16 include a middle cylindrical surface and an outer peripheral annular surface. The area surrounded by the middle cylindrical surface of the central umbrella-shaped stabilizer 12, the outer peripheral annular surface and the refractory ring 25 at the rear end of the diverter ring 14 forms an inner annular cavity return vortex 26. The area surrounded by the middle cylindrical surface, the outer peripheral annular surface and the refractory ring 25 at the rear end of the diverter ring 14 of the umbrella-shaped annular stabilizer 16 forms an intermediate annular cavity return vortex 29. The area surrounded by the middle cylindrical surface, the outer peripheral annular surface of the umbrella-shaped annular stabilizer 16 and the outer annular grid 18 forms an outer annular cavity return vortex 30.

[0035] See also Figure 1 As shown, the diverter ring 14 can be divided into a front section and a rear end according to the connection position of the intermediate annular grid 15. The half ring of the front section forms an annular convergence channel with the conical outer surfaces of the central umbrella-shaped stabilizer 12 and the umbrella-shaped annular stabilizer 16 respectively, and the half ring of the rear section is connected to the refractory ring 25 as a whole.

[0036] Further, see Figure 4 As shown, the inner ring grille 13 , the middle ring grille 15 and the outer ring grille 18 all include a plurality of grille blades 23 distributed along the circumferential direction, and a grille channel 24 is formed between two adjacent grille blades 23 .

[0037] Furthermore, the distances between two adjacent grille blades 23 in the inner ring grille 13 , the middle ring grille 15 and the outer ring grille 18 are all the same.

[0038] Furthermore, the inner ring grid 13, the middle ring grid 15 and the outer ring grid 18 are on the same horizontal plane.

[0039] Furthermore, the inner annular grid 13 is fixed on the inner peripheral wall of the diverter ring 14 , and the middle annular grid 15 is fixed on the outer peripheral wall of the diverter ring 14 .

[0040] By forming the inner annular cavity recirculation vortex 26, the middle annular cavity recirculation vortex 29 and the outer annular cavity recirculation vortex 30, a three-zone micro-premixed combustion is formed to achieve efficient and stable combustion and low NOx emissions. During operation, the fresh air flowing through the streamlined leading edge of the central umbrella-shaped stabilizer 12 entrains the hydrogen ejected from dozens of circumferentially discrete secondary hydrogen injection holes 21 to be uniformly and efficiently micro-premixed in the annular convergent channel and the inner annular grid 13, effectively preventing the "flashback" problem of hydrogen combustion. The inner annular cavity recirculation vortex 26 ensures good combustion stability performance, and the refractory coating 22 prevents the central umbrella-shaped stabilizer 12 from ablation. The hydrogen ejected from the inner oblique injection hole 27 and the outer oblique injection hole 28 are accelerated to mix with the incoming air in the converging middle ring channel and outer ring channel and the middle ring channel grid 15 and the outer ring channel grid 18 respectively, and then are entrained by the air flow into the middle ring cavity recirculation vortex 29 and the outer ring cavity recirculation vortex 30 formed on the leeward side of the refractory coating 22 of the umbrella-shaped annular stabilizer 16 for stable combustion. The converging middle ring channel and outer ring channel and the middle ring channel grid 15 and the outer ring channel grid 18, on the one hand, effectively prevent the "backfire" of hydrogen combustion, and on the other hand, improve the mixing quality and spatial distribution uniformity of hydrogen fuel in the premixing process, effectively reduce the maximum gas temperature in the combustion zone, and thus reduce NOx emissions.

[0041] The combustion chamber head of the present invention adopts a hydrogen combustion mode of high-speed jet-annular discrete hydrogen cross-flow micro-premixing in a convergent annular channel. The nozzle adopts a main and auxiliary two-stage hydrogen supply nozzle. The micro-premixed combustion adopts a micro-mixing structure composed of an inner annular channel grid, an intermediate annular channel grid and an outer annular channel grid, and a unique three-zone annular cavity recirculation vortex composed of an umbrella-shaped stabilizer, a diverter ring and an umbrella-shaped annular stabilizer. It can achieve full and uniform mixing of hydrogen fuel with air in the entire combustion zone before combustion, effectively avoiding hydrogen combustion backfire, hydrogen concentration 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 NOx emissions.

[0042] Obviously, those skilled in the art should understand that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the embodiments of the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0043] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description 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 may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber head, characterized in that: The combustion chamber head comprises a head cap (19), a hydrogen supply rod, and a central umbrella-shaped stabilizer (12), a flow divider ring (14), and an umbrella-shaped annular stabilizer (16) coaxially arranged outward along a central axis (20); a circular air inlet hole (191) is provided at the center of the head cap (19); The hydrogen supply nozzles of the hydrogen supply rod extend into the inner cavities (120) of the central umbrella-shaped stabilizer (12) and the umbrella-shaped annular stabilizer (16) respectively, and the central umbrella-shaped stabilizer (12) and the umbrella-shaped annular stabilizer (16) are both provided with hydrogen injection holes that are in communication with the inner cavities (120); An inner annular grid (13) is provided between the central umbrella-shaped stabilizer (12) and the diverter ring (14), an intermediate annular grid (15) is provided between the diverter ring (14) and the umbrella-shaped annular stabilizer (16), and an outer annular grid (18) is provided between the umbrella-shaped annular stabilizer (16) and the inner peripheral wall of the head cap (19).

2. The umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber head according to claim 1 is characterized in that: The central umbrella-shaped stabilizer (12) and the umbrella-shaped annular stabilizer (16) both comprise a streamlined leading edge surface (121), a conical outer surface (122) and a rear end surface (123); the conical outer surface (122) is provided with a plurality of hydrogen injection holes in a circumferential direction and connected to the inner cavity (120).

3. The umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber head according to claim 2 is characterized in that: The hydrogen injection hole is an inclined hole opened along the air flow direction.

4. The umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber head according to claim 2 is characterized in that: The rear end surface (123) is coated with a refractory coating (22).

5. The umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber head according to claim 2 is characterized in that: The rear end surface (123) includes a middle cylindrical surface and an outer peripheral annular surface. The area enclosed by the middle cylindrical surface of the central umbrella-shaped stabilizer (12), the outer peripheral annular surface and the refractory ring (25) at the rear end of the diverter ring (14) forms an inner annular cavity recirculation vortex (26). The area enclosed by the middle cylindrical surface of the umbrella-shaped annular stabilizer (16), the outer peripheral annular surface and the refractory ring (25) at the rear end of the diverter ring (14) forms an intermediate annular cavity recirculation vortex (29). The area enclosed by the middle cylindrical surface of the umbrella-shaped annular stabilizer (16), the outer peripheral annular surface and the outer annular grid (18) forms an outer annular cavity recirculation vortex (30).

6. The umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber head according to claim 1 is characterized in that: The inner ring grille (13), the middle ring grille (15) and the outer ring grille (18) all include a plurality of grille blades (23) distributed along the circumferential direction, and a grille channel (24) is formed between two adjacent grille blades (23).

7. The umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber head according to claim 6 is characterized in that: The distances between two adjacent grille blades (23) in the inner ring grille (13), the middle ring grille (15) and the outer ring grille (18) are all the same.

8. The umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber head according to claim 1 or 6, characterized in that: The inner ring grid (13), the middle ring grid (15) and the outer ring grid (18) are on the same horizontal plane.

9. The umbrella-shaped coaxial three-zone micro-mixed hydrogen fuel combustion chamber head according to claim 1 is characterized in that: The inner annular grid (13) is fixed on the inner peripheral wall of the diverter ring (14), and the middle annular grid (15) is fixed on the outer peripheral wall of the diverter ring (14).

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