Hydrogen fuel staged combustion unit, full annulus combustor, and aircraft engine

Abstract

The application relates to the technical field of hydrogen fuel engines and discloses a hydrogen fuel staged combustion unit, a full-ring combustion chamber and an aero-engine. The hydrogen fuel staged combustion unit comprises a shell and a nozzle. An air flow cavity is formed in the shell. A combustion cavity is formed by the shell. The air flow cavity is communicated with the combustion cavity. The nozzle is provided with at least two nozzles. The at least two nozzles are arranged at intervals along the engine axis direction. The nozzle is arranged on the shell. A hydrogen fuel cavity is formed in the nozzle. The first end of the nozzle is adapted to communicate with hydrogen fuel. The second end of the nozzle is arranged in the combustion cavity. A group of injection holes are arranged on the nozzle. The group of injection holes is arranged close to the second end of the nozzle. The group of injection holes penetrates the nozzle to communicate the hydrogen fuel cavity with the combustion cavity. At least two nozzles are arranged along the engine axis direction. The hydrogen gas entering the combustion cavity is mixed with the air in the combustion cavity more sufficiently. The mixing uniformity of the hydrogen gas is improved. The temperature of the combustion cavity is reduced. The emission is reduced.

Description

Technical Field

[0001] This invention relates to the field of hydrogen fuel engine technology, specifically to a hydrogen fuel staged combustion unit, an annular combustion chamber, and an aero-engine. Background Technology

[0002] The combustion chamber is the region in an aircraft engine that converts the chemical energy of the fuel into thermal energy. It is responsible for heating the high-pressure air, after being compressed by the compressor, to the temperature allowed before the turbine, so that these high-temperature, high-pressure gases can expand and do work within the turbine and exhaust system, thereby driving the engine.

[0003] Some existing aircraft engines use hydrogen as fuel. The hydrogen fuel enters the combustion chamber in a gaseous state. However, the hydrogen is burned before it is evenly mixed, resulting in high temperatures in the main combustion zone of the combustion chamber and high NOx emissions. Summary of the Invention

[0004] In view of this, the present invention provides a hydrogen fuel staged combustion unit, an annular combustion chamber, and an aero-engine to solve the problem of high temperature in the main combustion zone of the combustion chamber and high NOx emissions.

[0005] In a first aspect, the present invention provides a hydrogen fuel staged combustion unit, comprising: a housing, wherein an air flow chamber is formed inside the housing, and a combustion chamber is formed within the housing, the air flow chamber being in communication with the combustion chamber; and nozzles, wherein at least two nozzles are provided, the at least two nozzles being spaced apart along the engine axis, the nozzles being disposed on the housing, a hydrogen fuel chamber being formed within the nozzles, a first end of the nozzles being adapted to communicate with hydrogen fuel, a second end of the nozzles being disposed within the combustion chamber, and an assembly of nozzle orifices being formed on the nozzles, the assembly of nozzle orifices being disposed near the second end of the nozzles, the assembly of nozzle orifices penetrating the nozzles to communicate the hydrogen fuel chamber and the combustion chamber.

[0006] Beneficial effects: By setting at least two nozzles along the engine axis, the hydrogen entering the combustion chamber is mixed more thoroughly with the air in the combustion chamber, improving the uniformity of hydrogen mixing, thereby reducing the temperature of the combustion chamber and thus reducing emissions.

[0007] In one optional embodiment, the nozzle group includes at least one first nozzle and a plurality of second nozzles. The first nozzle is formed at the second end of the nozzle along the axial extension direction of the nozzle, and the second nozzles are formed on the sidewall of the nozzle. The plurality of second nozzles are arranged in a plurality of layers along the axial extension direction of the nozzle.

[0008] Beneficial effects: Hydrogen is injected into the combustion chamber through the first and second nozzles, making it easier for the hydrogen to mix with the air in the combustion chamber, further improving the uniformity of hydrogen mixing, thereby reducing the temperature of the combustion chamber and thus reducing emissions.

[0009] In one optional embodiment, the diameter of the first nozzle is D1, which satisfies 0.5mm≤D1≤1.2mm.

[0010] Beneficial effect: By limiting the diameter of the first nozzle, a large hydrogen flow rate is ensured while preventing high-temperature combustion gas from flowing back into the nozzle through the first nozzle.

[0011] In one optional embodiment, the diameter of the second nozzle is D2, which satisfies 0.4mm≤D2≤1.0mm.

[0012] Beneficial effects: By limiting the diameter of the second nozzle, the flow rate of hydrogen gas ejected from the second nozzle is ensured to be relatively fast, while preventing the increase in processing difficulty and cost caused by the nozzle diameter being too small.

[0013] In one alternative embodiment, the hydrogen fuel staged combustion unit further includes a control component adapted to adjust the hydrogen fuel equivalence ratio and jet velocity of each of the nozzles.

[0014] Beneficial effects: By setting up control components to adjust the hydrogen fuel equivalence ratio and jet velocity of each nozzle, emissions can be reduced while ensuring stable combustion of the mixed gas in the combustion chamber.

[0015] In one alternative embodiment, two nozzles are provided, and the axial extension directions of the two nozzles intersect.

[0016] In one alternative embodiment, the hydrogen fuel staged combustion unit further includes a vortex generator disposed on the side of the housing near the combustion chamber, the vortex generator being adapted to connect the airflow chamber and the combustion chamber.

[0017] Beneficial effects: By creating vortices in the gas to ensure uniform mixing of hydrogen and air, the vortex generator helps to ensure effective mixing of hydrogen and air, thereby improving the combustion efficiency of hydrogen fuel and engine performance.

[0018] In one optional embodiment, the housing includes a casing, an inner ring of the flame tube, and an outer ring of the flame tube. The two ends of the casing are connected to the inner ring and the outer ring of the flame tube, respectively. The inner ring and the outer ring of the flame tube are connected to enclose and form the airflow cavity. The combustion cavity is formed between the inner ring and the outer ring of the flame tube. The nozzle passes through the casing and one of the inner and outer rings of the flame tube in sequence. The inner and outer rings of the flame tube are provided with perforations to connect the airflow cavity and the combustion cavity.

[0019] Secondly, the present invention also provides an annular combustion chamber, including the aforementioned hydrogen fuel staged combustion unit, wherein a plurality of hydrogen fuel staged combustion units are provided, and the plurality of hydrogen fuel staged combustion units are distributed in a circumferential array along the engine.

[0020] Thirdly, the present invention also provides an aircraft engine including the aforementioned annular combustion chamber. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of a hydrogen fuel staged combustion unit according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the nozzle structure according to an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the gas flow in the hydrogen fuel staged combustion unit according to an embodiment of the present invention.

[0025] Explanation of reference numerals in the attached figures:

[0026] 10. Shell; 11. Casing shell; 12. Inner ring of flame tube; 13. Outer ring of flame tube; 14. Perforation; 15. Airflow chamber; 16. Combustion chamber; 20. Nozzle; 21. Nozzle group; 211. First nozzle; 212. Second nozzle; 22. Hydrogen fuel chamber; 30. Swirler. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The following is combined with Figures 1 to 3 The following describes embodiments of the present invention.

[0029] Example 1

[0030] like Figure 1As shown, this embodiment provides a hydrogen fuel staged combustion unit, which includes a housing 10 and nozzles 20. An airflow chamber 15 is formed inside the housing 10, and a combustion chamber 16 is formed within the housing 10. The airflow chamber 15 communicates with the combustion chamber 16. Two nozzles 20 are provided, spaced apart along the engine axis, and their axial extension directions intersect. The nozzles 20 are mounted on the housing 10, and a hydrogen fuel chamber 22 is formed within each nozzle 20. The first end of the nozzle 20 communicates with hydrogen fuel, and the second end of the nozzle 20 is located within the combustion chamber 16. An orifice group 21 is formed on the nozzle 20, positioned near the second end of the nozzle 20, and penetrates the nozzle 20 to connect the hydrogen fuel chamber 22 and the combustion chamber 16.

[0031] The hydrogen fuel staged combustion unit of this embodiment uses two nozzles 20 arranged along the engine axis to make the hydrogen entering the combustion chamber 16 mix more fully with the air in the combustion chamber 16, improve the mixing uniformity of hydrogen, thereby reducing the temperature of the combustion chamber 16 and thus reducing emissions.

[0032] It should be noted that in related technologies, hydrogen fuel enters the combustion chamber 16 in a gaseous state. However, the hydrogen is burned before it is evenly mixed, resulting in a high temperature in the main combustion zone of the combustion chamber 16 and high NOx emissions. In this embodiment, hydrogen enters the combustion chamber 16 through two spaced nozzles 20, expanding the mixing area between hydrogen and air to improve the uniformity of hydrogen mixing and make combustion more uniform. This avoids the generation of local hot spots in the combustion chamber 16, thereby reducing the temperature of the combustion chamber 16. High-temperature areas accelerate NOx generation, thereby increasing the overall NOx emissions in the combustion chamber 16. The hydrogen fuel staged combustion unit in this embodiment reduces the temperature of the combustion chamber 16, thus also reducing NOx emissions.

[0033] It should be noted that those skilled in the art can adjust the specific number of nozzles 20 according to actual needs.

[0034] Specifically, the two nozzles are divided into a primary nozzle and a secondary nozzle. Please refer to [link / reference needed]. Figure 1 In the diagram, nozzle 20 on the right is the primary nozzle, and nozzle 20 on the left is the secondary nozzle.

[0035] For details, please refer to Figure 3 , Figure 3 A schematic diagram of gas flow within a hydrogen fuel staged combustion unit is shown, where dashed arrows represent air flow and solid arrows represent hydrogen flow.

[0036] like Figure 2As shown, in this embodiment, the nozzle group 21 includes a first nozzle 211 and a second nozzle 212. The first nozzle 211 is opened at the second end of the nozzle 20 along the axial extension direction of the nozzle 20, and the second nozzle 212 is opened on the side wall of the nozzle 20. The second nozzle 212 is provided with four layers along the axial extension direction of the nozzle 20.

[0037] Specifically, there is one first nozzle 211 and twenty-four second nozzles 212. Of course, those skilled in the art can adjust the specific number of the first nozzles 211 and the second nozzles 212, as well as the number of layers of the second nozzles 212, according to actual needs.

[0038] It is understood that the first nozzle 211 is opened along the axial extension direction of the nozzle 20, and the second nozzle 212 is opened on the side wall of the nozzle 20. When hydrogen enters the nozzle 20, it is preferentially sprayed into the combustion chamber 16 through the first nozzle 211. The hydrogen sprayed into the combustion chamber 16 through the first nozzle 211 ensures stable combustion in the combustion chamber 16, and the hydrogen sprayed into the combustion chamber 16 through the second nozzle 212 is sprayed at multiple angles to facilitate the mixing of hydrogen and air.

[0039] It is worth noting that hydrogen is injected into the combustion chamber 16 through the first nozzle 211 and the second nozzle 212, making it easier for the hydrogen to mix with the air in the combustion chamber 16, further improving the uniformity of hydrogen mixing, thereby reducing the temperature of the combustion chamber 16 and thus reducing emissions.

[0040] In this embodiment, the diameter of the first nozzle orifice 211 of the primary nozzle is 0.6 mm, and the diameter of the first nozzle orifice 211 of the secondary nozzle is 0.8 mm.

[0041] It should be noted that those skilled in the art can adjust the specific value of the diameter D1 of the first spray hole 211 on each nozzle 20 according to actual needs, so as to satisfy 0.5mm≤D1≤1.2mm.

[0042] It should be noted that there is a large backflow vortex in the combustion chamber 16. The size of the first nozzle 211 affects the flow rate of hydrogen. The hydrogen ejected from the first nozzle 211 can resist the high-temperature combustion gas in the opposite direction, thus isolating the nozzle 20 from the high-temperature combustion gas in the combustion chamber 16. When D1 < 0.5 mm, the flow rate of hydrogen ejected from the first nozzle 211 is small, and the effect of hydrogen resisting the backflow of high-temperature combustion gas is poor. When D1 > 1.2 mm, the diameter of the first nozzle 211 is too large, and the large flow rate of hydrogen cannot resist the high-temperature combustion gas and easily flows back into the first nozzle 211.

[0043] It is worth noting that by limiting the diameter of the first nozzle 211, a large hydrogen flow rate is ensured while preventing high-temperature combustion gas from flowing back into the nozzle 20 through the first nozzle 211.

[0044] In this embodiment, the diameter of the second nozzle 212 of the primary nozzle is 0.5 mm, and the diameter of the second nozzle 212 of the secondary nozzle is 0.7 mm.

[0045] It should be noted that those skilled in the art can adjust the specific value of the diameter D2 of the second nozzle 212 according to actual needs, so as to satisfy 0.4mm≤D2≤1.0mm.

[0046] It should be noted that, under the same flow rate, the smaller the orifice, the faster the flow rate. When D2 > 1.0 mm, the size of the second nozzle 212 is too large, which affects the flow rate of hydrogen under the same flow rate. When D2 < 0.4 mm, it will increase the processing difficulty and cost of the nozzle 20.

[0047] It is worth noting that by limiting the diameter of the second nozzle 212, while ensuring that the flow rate of hydrogen gas ejected from the second nozzle 212 is relatively fast, it is prevented that the aperture is too small, which would increase the processing difficulty and cost.

[0048] In this embodiment, the hydrogen fuel staged combustion unit further includes a control component (not shown in the figure), which is adapted to adjust the hydrogen fuel equivalence ratio and jet velocity of each nozzle 20.

[0049] It should be noted that hydrogen has a wide flammability range and can burn stably at a lower equivalence ratio. In this embodiment, the two nozzles 20 are arranged at intervals along the engine axis. The fuel ratio of the primary and secondary nozzles can be adjusted by the control component to achieve the optimal temperature distribution during combustion.

[0050] Furthermore, by adjusting the two nozzles 20 separately through the control components, the first-stage nozzle plays a role in stabilizing combustion, while the second-stage nozzle uses a low equivalence ratio strong jet to improve the uniformity of hydrogen and air mixing in the combustion chamber 16 and reduce the combustion temperature, so as to further reduce emissions under the premise of stable combustion.

[0051] It should be noted that the axial distance between the primary nozzle and the secondary nozzle can also be adjusted according to the combustion characteristics of hydrogen to ensure uniform temperature distribution within the combustion chamber 16.

[0052] like Figure 1 As shown, in this embodiment, the hydrogen fuel staged combustion unit further includes a vortex generator 30, which is disposed on the side of the housing 10 near the combustion chamber 16 and connects the air flow chamber 15 and the combustion chamber 16.

[0053] Specifically, after the air enters the vortex generator 30, it is guided by the turbine blades and rotates. This rotational motion increases the turbulence and mixing effect of the air, which helps to fully mix hydrogen and air in the subsequent combustion process.

[0054] It is worth noting that the vortex generator 30 helps ensure effective mixing of hydrogen and air by creating vortices in the gas so that they can be mixed evenly with hydrogen and air, thereby improving the combustion efficiency of hydrogen fuel and engine performance.

[0055] like Figure 1 As shown, the housing 10 includes a casing 11, an inner ring 12 of the flame tube, and an outer ring 13 of the flame tube. The two ends of the casing 11 are connected to the inner ring 12 and the outer ring 13 of the flame tube, respectively. The inner ring 12 and the outer ring 13 of the flame tube are connected to form an airflow cavity 15. A combustion cavity 16 is formed between the inner ring 12 and the outer ring 13 of the flame tube. The nozzle 20 passes through the casing 11 and one of the inner ring 12 and the outer ring 13 of the flame tube in sequence. The inner ring 12 and the outer ring 13 of the flame tube are provided with through holes 14 to connect the airflow cavity 15 and the combustion cavity 16.

[0056] For details, please refer to Figure 1 In the figure, the bottom of the combustion chamber 16 has an opening to facilitate the outward flow of gas from the combustion chamber 16. The inner ring 12 and the outer ring 13 of the flame tube near the opening have a smooth arc-shaped structure. The smooth arc-shaped structure helps to reduce the resistance to gas flow, so that the gas can flow quickly to the opening.

[0057] Example 2

[0058] This embodiment provides a full-annular combustion chamber, including the hydrogen fuel staged combustion unit of Embodiment 1. Several hydrogen fuel staged combustion units are arranged in a circumferential array along the engine.

[0059] Example 3

[0060] This embodiment provides an aero engine, including the annular combustion chamber of Embodiment 2.

[0061] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and all such modifications and variations fall within the scope defined by the invention.

Claims

1. A staged combustion unit for hydrogen fuel, characterized in that, include: The housing (10) has an air flow cavity (15) formed inside it, and the housing (10) encloses a combustion cavity (16), with the air flow cavity (15) communicating with the combustion cavity (16). The combustion chamber (16) has a "C" shaped cross section, a reflux vortex inside the combustion chamber (16), and an opening at the bottom of the combustion chamber (16) to facilitate the outward flow of gas from the combustion chamber (16). At least two nozzles (20) are provided, and the at least two nozzles (20) are spaced apart along the engine axis. The nozzles (20) are provided on the housing (10). A hydrogen fuel chamber (22) is formed inside the nozzle (20). The first end of the nozzle (20) is adapted to communicate with hydrogen fuel. The second end of the nozzle (20) is provided in the combustion chamber (16). A group of nozzle holes (21) is provided on the nozzle (20). The group of nozzle holes (21) is provided close to the second end of the nozzle (20). The group of nozzle holes (21) penetrates the nozzle (20) to communicate the hydrogen fuel chamber (22) and the combustion chamber (16). The nozzle group (21) includes at least one first nozzle (211), which is opened at the second end of the nozzle (20) along the axial extension direction of the nozzle (20). The diameter of the first nozzle (211) is D1, which satisfies 0.5mm≤D1≤1.2mm.

2. The hydrogen fuel staged combustion unit according to claim 1, characterized in that, The nozzle group (21) includes a plurality of second nozzles (212), which are formed on the side wall of the nozzle (20). The plurality of second nozzles (212) are arranged in a plurality of layers along the axial extension direction of the nozzle (20).

3. The hydrogen fuel staged combustion unit according to claim 2, characterized in that, The diameter of the second nozzle (212) is D2, which satisfies 0.4mm≤D2≤1.0mm.

4. The hydrogen fuel staged combustion unit according to any one of claims 1-3, characterized in that, The hydrogen fuel staged combustion unit also includes a control component adapted to adjust the hydrogen fuel equivalence ratio and jet velocity of each of the nozzles (20).

5. The hydrogen fuel staged combustion unit according to any one of claims 1-3, characterized in that, There are two nozzles (20), and the axial extension directions of the two nozzles (20) intersect.

6. The hydrogen fuel staged combustion unit according to any one of claims 1-3, characterized in that, The hydrogen fuel staged combustion unit also includes a vortex generator (30), which is disposed on the side of the housing (10) near the combustion chamber (16) and is adapted to connect the air flow chamber (15) and the combustion chamber (16).

7. The hydrogen fuel staged combustion unit according to any one of claims 1-3, characterized in that, The housing (10) includes a casing (11), an inner ring (12) of the flame tube, and an outer ring (13) of the flame tube. The two ends of the casing (11) are respectively connected to the inner ring (12) of the flame tube and the outer ring (13) of the flame tube. The inner ring (12) of the flame tube and the outer ring (13) of the flame tube are connected to form the air flow cavity (15). The combustion cavity (16) is formed between the inner ring (12) of the flame tube and the outer ring (13) of the flame tube. The nozzle (20) passes through the casing (11), the inner ring (12) of the flame tube, and the outer ring of the flame tube in sequence. The inner ring (12) of the flame tube and the outer ring (13) of the flame tube are provided with perforations (14) to connect the air flow cavity (15) and the combustion cavity (16).

8. A full-annular combustion chamber, characterized in that, The system includes a hydrogen fuel staged combustion unit as described in any one of claims 1 to 7, wherein a plurality of hydrogen fuel staged combustion units are provided, and the plurality of hydrogen fuel staged combustion units are distributed in a circumferential array along the engine.

9. An aircraft engine, characterized in that, Includes the full-annular combustion chamber as described in claim 8.

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