Hydrogen fuel staged combustion unit, full-ring combustion chamber and aero-engine

Abstract

The invention 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 flowing cavity is formed in the shell, a combustion cavity is defined by the shell, and the air flowing cavity communicates with the combustion cavity; the at least two nozzles are arranged in the axis direction of the engine at intervals, the nozzles are arranged on the shell, hydrogen fuel cavities are formed in the nozzles, the first ends of the nozzles are suitable for being communicated with hydrogen fuel, the second ends of the nozzles are arranged in the combustion cavity, spraying hole sets are formed in the nozzles, and the spraying hole sets are arranged close to the second ends of the nozzles. The spraying hole set penetrates through the nozzle to communicate the hydrogen fuel cavity with the combustion cavity. The at least two nozzles are arranged in the axis direction of the engine, so that hydrogen entering the combustion cavity is more fully mixed with air in the combustion cavity, the mixing uniformity of the hydrogen is improved, the temperature of the combustion cavity is reduced, and then emission is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen fuel engines, and in particular to a hydrogen fuel staged combustion unit, a full-annular combustion chamber and an aero-engine. Background Art

[0002] The combustion chamber is the area in an aircraft engine that converts the chemical energy in the fuel into thermal energy. It is responsible for heating the high-pressure air after the compressor is boosted to the temperature allowed before the turbine, so that these high-temperature and high-pressure gases can enter the turbine and exhaust device to expand and do work, thereby driving the engine to operate.

[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 a higher temperature in the main combustion zone of the combustion chamber and higher NOx emissions. Summary of the invention

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

[0005] In the first aspect, the present invention provides a hydrogen fuel staged combustion unit, comprising: a shell, an air flow chamber is formed inside the shell, the shell encloses a combustion chamber, and the air flow chamber is connected to the combustion chamber; a nozzle, at least two of which are provided, and at least two of the nozzles are spaced apart along the engine axis direction, the nozzle is provided on the shell, a hydrogen fuel chamber is formed inside the nozzle, the first end of the nozzle is suitable for connecting with hydrogen fuel, the second end of the nozzle is provided in the combustion chamber, a spray hole group is opened on the nozzle, the spray hole group is provided near the second end of the nozzle, and the spray hole group passes through the nozzle to connect the hydrogen fuel chamber with the combustion chamber.

[0006] Beneficial effect: By arranging at least two nozzles along the axial direction of the engine, the hydrogen entering the combustion chamber is mixed more fully with the air in the combustion chamber, thereby improving the mixing uniformity of the hydrogen, thereby reducing the temperature of the combustion chamber and further reducing emissions.

[0007] In an optional embodiment, the spray hole group includes at least one first spray hole and several second spray holes, the first spray hole is opened at the second end of the nozzle along the axial extension direction of the nozzle, the second spray hole is opened on the side wall of the nozzle, and the several second spray holes are arranged in several layers along the axial extension direction of the nozzle.

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

[0009] In an optional implementation, the diameter of the first spray hole is D1, satisfying 0.5 mm ≤ D1 ≤ 1.2 mm.

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

[0011] In an optional implementation, the diameter of the second spray hole is D2, satisfying 0.4 mm ≤ D2 ≤ 1.0 mm.

[0012] Beneficial effect: By limiting the diameter of the second spray hole, the flow rate of hydrogen sprayed from the second spray hole is ensured to be fast while preventing the increase of processing difficulty and cost caused by the hole diameter being too small.

[0013] In an optional embodiment, the hydrogen fuel staged combustion unit further comprises a control component, wherein the control component is adapted to adjust the hydrogen fuel equivalence ratio and the jet velocity of each of the nozzles.

[0014] Beneficial effect: By setting the control component, it is convenient to adjust the hydrogen fuel equivalence ratio and the jet velocity of each nozzle, thereby reducing emissions while ensuring stable combustion of the mixed gas in the combustion chamber.

[0015] In an optional embodiment, two nozzles are provided, and the axial extension directions of the two nozzles are intersecting.

[0016] In an optional embodiment, the hydrogen fuel staged combustion unit further includes a swirler, which is disposed on a side of the shell close to the combustion chamber, and is suitable for connecting the air flow chamber and the combustion chamber.

[0017] Beneficial Effects: The swirler helps ensure efficient mixing of hydrogen and air by creating a swirl in the gas so that the hydrogen and air are evenly mixed, thereby improving the combustion efficiency of the hydrogen fuel and the engine performance.

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

[0019] In a second aspect, the present invention further provides a full-annular combustion chamber, comprising the above-mentioned hydrogen fuel staged combustion unit, wherein a plurality of the hydrogen fuel staged combustion units are provided, and the plurality of the hydrogen fuel staged combustion units are distributed in an array along the circumference of the engine.

[0020] In a third aspect, the present invention further provides an aircraft engine comprising the above-mentioned full-annular combustion chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

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

[0023] Figure 2 A schematic structural diagram of a nozzle according to an embodiment of the present invention;

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

[0025] Description of reference numerals:

[0026] 10. Shell; 11. Casing; 12. Flame tube inner ring; 13. Flame tube outer ring; 14. Perforation; 15. Air flow chamber; 16. Combustion chamber; 20. Nozzle; 21. Spray hole group; 211. First spray hole; 212. Second spray hole; 22. Hydrogen fuel chamber; 30. Vortexer. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0028] Combine the following Figures 1 to 3 , describing an embodiment of the present invention.

[0029] Example 1

[0030] like Figure 1As shown, this embodiment provides a hydrogen fuel staged combustion unit, which includes a shell 10 and a nozzle 20. An air flow chamber 15 is formed inside the shell 10, and a combustion chamber 16 is formed by the shell 10, and the air flow chamber 15 is connected to the combustion chamber 16; two nozzles 20 are provided, and the two nozzles 20 are arranged at intervals along the axis direction of the engine, and the axial extension directions of the two nozzles 20 are arranged to intersect. The nozzle 20 is arranged on the shell 10, and a hydrogen fuel chamber 22 is formed in the nozzle 20. The first end of the nozzle 20 is connected to the hydrogen fuel, and the second end of the nozzle 20 is arranged in the combustion chamber 16. A spray hole group 21 is opened on the nozzle 20, and the spray hole group 21 is arranged near the second end of the nozzle 20. The spray hole group 21 passes through the nozzle 20 to connect the hydrogen fuel chamber 22 with the combustion chamber 16.

[0031] The hydrogen fuel staged combustion unit of this embodiment is applied, by setting two nozzles 20 along the axial direction of the engine, so that the hydrogen entering the combustion chamber 16 and the air in the combustion chamber 16 are mixed more fully, improving the mixing uniformity of the hydrogen, thereby reducing the temperature of the combustion chamber 16 and further reducing emissions.

[0032] It should be noted that in the related art, hydrogen fuel enters the combustion chamber 16 in a gaseous state. However, the hydrogen is burned before it is evenly mixed, resulting in a higher temperature in the main combustion zone of the combustion chamber 16 and higher NOx emissions. In the present embodiment, hydrogen enters the combustion chamber 16 through two nozzles 20 arranged at intervals, respectively, and the mixing area of ​​hydrogen and air is expanded to improve the mixing uniformity of hydrogen, making the combustion more uniform and avoiding the generation of local hot spots in the combustion chamber 16, thereby reducing the temperature of the combustion chamber 16. The high temperature area will accelerate the generation of NOx, thereby increasing the overall NOx emissions in the combustion chamber 16. The hydrogen fuel staged combustion unit of the present embodiment reduces the temperature of the combustion chamber 16, thereby also reducing NOx emissions.

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

[0034] Specifically, the two nozzles 20 are divided into a primary nozzle and a secondary nozzle, see Figure 1 The nozzle 20 on the right side of the figure is a primary nozzle, and the nozzle 20 on the left side of the figure is a secondary nozzle.

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

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

[0037] Specifically, one first spray hole 211 is provided and twenty-four second spray holes 212 are provided. Of course, those skilled in the art can adjust the specific numbers of the first spray holes 211 and the second spray holes 212 and the number of layers of the second spray holes 212 according to actual needs.

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

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

[0040] In this embodiment, the diameter of the first spray hole 211 of the first-stage nozzle is 0.6 mm, and the diameter of the first spray hole 211 of the second-stage 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 to satisfy 0.5 mm ≤ D1 ≤ 1.2 mm.

[0042] It should be noted that there is a large backflow vortex in the combustion chamber 16, and the size of the first spray hole 211 affects the flow rate of hydrogen. The hydrogen sprayed from the first spray hole 211 can resist the high-temperature combustion gas in the opposite direction, and plays a role in isolating the nozzle 20 from the high-temperature combustion gas in the combustion chamber 16. When D1 is less than 0.5 mm, the flow rate of hydrogen sprayed from the first spray hole 211 is small, and the effect of hydrogen resisting the backflow of the high-temperature combustion gas is poor. When D1 is greater than 1.2 mm, the diameter of the first spray hole 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 spray hole 211.

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

[0044] In this embodiment, the diameter of the second spray hole 212 of the first-stage nozzle is 0.5 mm, and the diameter of the second spray hole 212 of the second-stage 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 spray hole 212 according to actual needs to satisfy 0.4 mm ≤ D2 ≤ 1.0 mm.

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

[0047] It is worth noting that by limiting the diameter of the second spray hole 212, while ensuring a faster flow rate of hydrogen sprayed from the second spray hole 212, it prevents the increase of processing difficulty and cost due to the hole diameter being too small.

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

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

[0050] Furthermore, the two nozzles 20 are adjusted separately through the control component, so that the first-stage nozzle plays a role in stabilizing combustion, and the second-stage nozzle adopts a low equivalence ratio strong jet method to improve the uniformity of the mixing of hydrogen and air in the combustion chamber 16 and reduce the combustion temperature, so as to further achieve emission reduction under the premise of stable combustion.

[0051] It should be noted that the axial distance between the primary nozzle and the secondary nozzle may also be adjusted according to the hydrogen combustion characteristics so as to achieve uniform temperature distribution in the combustion chamber 16 .

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

[0053] Specifically, after the air enters the vortex finder 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 the hydrogen and air in the subsequent combustion process.

[0054] It is worth noting that the swirler 30 helps to ensure effective mixing of hydrogen and air by causing the gas to generate swirl so as to be evenly mixed with the hydrogen and air, thereby improving the combustion efficiency of the hydrogen fuel and the engine performance.

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

[0056] For details, please refer to Figure 1 In the figure, a cavity opening is formed at the bottom of the combustion chamber 16 to facilitate gas flow outward from the combustion chamber 16. The partial structures of the flame tube inner ring 12 and the flame tube outer ring 13 near the cavity opening are smooth arc structures, which are conducive to reducing the resistance to gas flow, so that the gas can flow quickly to the cavity opening.

[0057] Example 2

[0058] The present embodiment provides a full-annular combustion chamber, including the hydrogen fuel staged combustion unit of Embodiment 1, wherein a plurality of hydrogen fuel staged combustion units are provided, and the plurality of hydrogen fuel staged combustion units are distributed in an array along the circumference of the engine.

[0059] Example 3

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

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

Claims

1. A hydrogen fuel staged combustion unit, characterized in that: include: A shell (10), wherein an air flow chamber (15) is formed inside the shell (10), and the shell (10) encloses a combustion chamber (16), and the air flow chamber (15) is communicated with the combustion chamber (16); Nozzles (20) are provided, and at least two of the nozzles (20) are arranged at intervals along the engine axis direction. The nozzles (20) are arranged on the housing (10), and a hydrogen fuel chamber (22) is formed in the nozzle (20). The first end of the nozzle (20) is suitable for connecting with hydrogen fuel, and the second end of the nozzle (20) is arranged in the combustion chamber (16). A spray hole group (21) is opened on the nozzle (20), and the spray hole group (21) is arranged near the second end of the nozzle (20). The spray hole group (21) penetrates the nozzle (20) to connect the hydrogen fuel chamber (22) with the combustion chamber (16).

2. The hydrogen fuel staged combustion unit according to claim 1, characterized in that: The spray hole group (21) comprises at least one first spray hole (211) and a plurality of second spray holes (212), wherein the first spray hole (211) is opened at the second end of the nozzle (20) along the axial extension direction of the nozzle (20), and the second spray hole (212) is opened on the side wall of the nozzle (20), and the plurality of second spray holes (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 first spray hole (211) is D1, satisfying 0.5 mm ≤ D1 ≤ 1.2 mm.

4. The hydrogen fuel staged combustion unit according to claim 2, characterized in that: The diameter of the second spray hole (212) is D2, satisfying 0.4 mm ≤ D2 ≤ 1.0 mm.

5. The hydrogen fuel staged combustion unit according to any one of claims 1 to 4, characterized in that: The hydrogen fuel staged combustion unit further comprises a control component, which is suitable for adjusting the hydrogen fuel equivalence ratio and the jet velocity of each of the nozzles (20).

6. The hydrogen fuel staged combustion unit according to any one of claims 1 to 4, characterized in that: Two nozzles (20) are provided, and the axial extension directions of the two nozzles (20) are arranged to intersect.

7. The hydrogen fuel staged combustion unit according to any one of claims 1 to 4, characterized in that: The hydrogen fuel staged combustion unit further comprises a swirler (30), wherein the swirler (30) is arranged on a side of the housing (10) close to the combustion chamber (16), and the swirler (30) is suitable for connecting the air flow chamber (15) and the combustion chamber (16).

8. The hydrogen fuel staged combustion unit according to any one of claims 1 to 4, characterized in that: The casing (10) comprises a casing (11), a flame tube inner ring (12) and a flame tube outer ring (13); the two ends of the casing (11) are respectively connected to the flame tube inner ring (12) and the flame tube outer ring (13); the flame tube inner ring (12) and the flame tube outer ring (13) are connected to enclose the air flow cavity (15); the combustion cavity (16) is formed between the flame tube inner ring (12) and the flame tube outer ring (13); the nozzle (20) sequentially penetrates the casing (11) and one of the flame tube inner ring (12) and the flame tube outer ring; the flame tube inner ring (12) and the flame tube outer ring (13) are provided with through holes (14) to connect the air flow cavity (15) and the combustion cavity (16).

9. A full-annular combustion chamber, characterized in that: It comprises the hydrogen fuel staged combustion unit according to any one of claims 1 to 8, wherein a plurality of the hydrogen fuel staged combustion units are provided, and the plurality of the hydrogen fuel staged combustion units are distributed in an array along the circumference of the engine.

10. An aircraft engine, characterized in that: Comprising the full-annular combustion chamber as described in claim 9.

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