Low-pollution combustion chamber

Abstract

The invention relates to the technical field of combustion chambers, and provides a low-pollution combustion chamber which comprises a flame tube head, two sparking plugs, a flame tube outer ring and a flame tube inner ring, and the flame tube head is arranged between the flame tube outer ring and the flame tube inner ring and connected with the flame tube outer ring and the flame tube inner ring. A plurality of lean oil combustion structures and two rich oil combustion structures are arranged on the head portion of the flame tube in the circumferential direction, the two sparking plugs are arranged at different positions of an outer ring of the flame tube respectively, and each sparking plug and the corresponding rich oil combustion structure are located in the same area. Therefore, the ignition and flameout performance of the rich oil combustion structure is improved, flames can be stabilized in a small state, the lean oil combustion structure is responsible for reducing the emission level of the whole combustion chamber, the defects of the lean oil combustion structure and the rich oil combustion structure are overcome, and meanwhile the advantages of the lean oil combustion structure and the rich oil combustion structure are combined.

Description

Technical Field

[0001] The invention belongs to the technical field of combustion chambers, and in particular relates to a low-pollution combustion chamber. Background Art

[0002] Low pollution is one of the main development directions of aircraft engine combustion chamber technology. At present, low pollution mainly consists of two types of combustion organization modes: rich combustion (Rich-Burn) and lean combustion (Lean-Burn).

[0003] Rich combustion refers to a process in which a small amount of air enters the combustion chamber from the head to form a richer head combustion zone. Since rich combustion has a lower temperature and the combustion zone is oxygen-deficient at this time, only a small amount of NOx is generated. However, rich combustion produces a large amount of CO and UHC, so a large amount of air needs to be injected into the combustion zone to participate in the reaction, and then the final combustion is completed in a lean state. This process is called Rich-Burn Quick-Quench Lean-Burn (RQL).

[0004] Lean-burn combustion involves introducing a large amount of air into the combustion chamber from the head, creating a leaner head combustion zone. Due to the lower temperature of lean-burn combustion, this effectively suppresses the formation of thermal NOx (nitrogen oxides), thereby reducing overall NOx emissions. There are two typical lean-burn combustion chambers: lean premixed prevaporized combustion (LPP) and lean direct injection (LDI). Lean direct injection is also known as lean direct mixing (LDM).

[0005] Currently, these two combustion organization modes have corresponding combustion chamber technical solutions, but the traditional RQL combustion chamber has less emission reduction potential than the lean-fuel combustion chamber, and the outlet temperature field is difficult to control. The ignition and extinguishing performance of the traditional lean-fuel combustion chamber is not as good as that of the RQL combustion chamber, and this problem needs to be solved urgently. Summary of the Invention

[0006] In response to the above problems, the present invention proposes a low-pollution combustion chamber, comprising: a flame tube head, two electric nozzles, a flame tube outer ring and a flame tube inner ring, the flame tube head being arranged between the flame tube outer ring and the flame tube inner ring and being connected to the flame tube outer ring and the flame tube inner ring respectively, a plurality of lean oil combustion structures and two rich oil combustion structures are arranged in the circumferential direction of the flame tube head, the two electric nozzles are respectively arranged at different positions of the flame tube outer ring, and each of the electric nozzles is respectively in the same area with each corresponding rich oil combustion structure.

[0007] Optionally, a plurality of first quenching and mixing holes are provided in the outer circumferential direction of the flame tube, and the plurality of first quenching and mixing holes are located in a region having one of the electric nozzles.

[0008] Optionally, a plurality of second quenching and mixing holes are provided in the circumferential direction in the flame tube, and the plurality of second quenching and mixing holes are located in a region having another of the electric nozzles.

[0009] Optionally, a mounting seat is provided on the outer ring of the flame tube, and the electric nozzle is provided on the mounting seat, and the electric nozzle is connected to the cavity formed by the outer ring of the flame tube and the inner ring of the flame tube through the mounting seat.

[0010] Optionally, it further includes a plurality of lean oil nozzles and two rich oil nozzles, wherein the plurality of lean oil nozzles are connected to the corresponding lean oil combustion structures, and each of the rich oil nozzles is respectively connected to the corresponding rich oil combustion structure.

[0011] Optionally, the multiple lean-oil nozzles include a nozzle rod, a sub-mold structure and a nozzle main mold, the sub-mold structure and the nozzle main mold are respectively arranged on the flame tube head, the nozzle rod is connected to the lean-oil combustion structure and the channels it has are respectively connected to the sub-mold structure and the nozzle main mold.

[0012] Optionally, the nozzle main mold includes a main mold nozzle and a main mold swirler, the main mold swirler is arranged on the cylinder, the cylinder is arranged on the lean combustion structure, and the main mold nozzle is opened on the cylinder.

[0013] Optionally, the sub-mold structure includes a sub-mold nozzle and a sub-mold air swirler, the sub-mold nozzle is arranged on the lean combustion structure, the sub-mold nozzle is connected to the oil circuit, the sub-mold air swirler is sleeved on the oil circuit, the oil circuit is connected to the nozzle rod, and the other end is connected to the sub-mold nozzle.

[0014] Optionally, the two oil-rich nozzles include a fuel nozzle and an oil-rich swirler, the fuel nozzle is connected to the oil-rich combustion structure, and the oil-rich swirler is sleeved on the fuel nozzle.

[0015] Optionally, it further includes a casing, wherein the flame tube head, the flame tube outer ring and the flame tube inner ring are all located in the casing, and the two electric nozzles respectively pass through the casing to the flame tube outer ring in the corresponding area.

[0016] The low-pollution combustion chamber provided by the present invention has the following advantages compared with the prior art:

[0017] By differentially arranging the flame tube head around its perimeter, the design includes multiple lean-burn configurations and two rich-burn configurations. The two rich-burn configurations have corresponding ignition nozzles, while maintaining the same total fuel and air supply within the flame tube head. This improves the rich-burn configuration's ignition performance and stabilizes the flame even at low speeds. The lean-burn configuration reduces emissions throughout the combustion chamber, addressing the shortcomings of both lean-burn and rich-burn configurations while combining their respective strengths.

[0018] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 A schematic diagram of a flame tube head of a low-pollution combustion chamber in an embodiment of the present invention is shown;

[0021] Figure 2 Shown Figure 1 Schematic diagram along the AA direction of the flame tube head;

[0022] Figure 3 Shown Figure 1 Schematic diagram along the BB direction of the flame tube head;

[0023] Figure 4 A schematic diagram of the outer ring of the flame tube of a low-pollution combustion chamber in an embodiment of the present invention is shown;

[0024] Figure 5 Shown Figure 4 Schematic diagram along the AA direction of the outer ring of the flame tube;

[0025] Figure 6 A schematic diagram of a lean burn nozzle of a low-pollution combustion chamber in an embodiment of the present invention is shown;

[0026] Figure 7 A schematic diagram of a low-pollution combustion chamber in an embodiment of the present invention is shown;

[0027] Figure 8 A schematic diagram of an oil-rich nozzle of a low-pollution combustion chamber in an embodiment of the present invention is shown.

[0028] In the figure, 1. flame tube head; 11. lean fuel combustion structure; 12. rich fuel combustion structure; 2. flame tube outer ring; 21. outer surface; 22. inner surface; 23. first quenching mixing hole; 24. mounting seat; 3. flame tube inner ring; 4. lean fuel nozzle; 41. nozzle rod; 42. secondary mold structure; 43. nozzle main mold; 431. main mold nozzle; 432. main mold swirler; 421. secondary mold nozzle; 422. secondary mold air swirler; 5. rich fuel nozzle; 51. fuel nozzle; 52. rich fuel swirler; 6. casing; 7. electric nozzle. DETAILED DESCRIPTION

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only 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 ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0030] like Figure 1 As shown, the present invention provides a low-pollution combustion chamber, comprising: specifically referring to 1 and 2, a flame tube head 1, two electric nozzles 7, a flame tube outer ring 2, and a flame tube inner ring 3. The flame tube head 1 is arranged between the flame tube outer ring 2 and the flame tube inner ring 3 and is connected to the flame tube outer ring 2 and the flame tube inner ring 3 respectively. A plurality of lean fuel combustion structures 11 and two rich fuel combustion structures 12 are provided circumferentially of the flame tube head 1. The two electric nozzles 7 are respectively arranged at different positions on the flame tube outer ring 2, and each electric nozzle 7 is in the same area as a corresponding rich fuel combustion structure 12. The flame tube head 1 is arranged in a differentiated manner circumferentially, that is, it includes a plurality of lean fuel combustion structures 11 and two rich fuel combustion structures 12, and the design areas of the two rich fuel combustion structures 12 have corresponding ignition electric nozzles 7, but the total fuel supply and gas supply of the flame tube head 1 must be kept consistent. This improves the flameout performance of the rich-burning structure 12 and stabilizes the flame even at low speeds. The lean-burning structure 11 reduces emissions throughout the combustion chamber, resolving the shortcomings of both lean-burning structures 11 and 12 while combining their advantages. Furthermore, the design characteristics of the rich-burning structure 12 are based on the structure of a rich-fuel (RQL) nozzle, while the design characteristics of the lean-burning structure 11 are based on the structure of a lean-fuel nozzle.

[0031] like Figure 4 and Figure 5As shown, in one embodiment, a plurality of first quenching mixing holes 23 are provided in the circumferential direction of the outer ring 2 of the flame tube, and the plurality of first quenching mixing holes 23 are located in the area having one of the nozzles 7. It should be noted that, through the plurality of first quenching mixing holes 23, efficient mixing, temperature control and emission optimization of the combustion chamber are achieved, thereby achieving low-pollution combustion. In addition, the nozzle 7 and the first quenching mixing holes 23 are in the same area or the same cross-section, and the nozzle 7 and the first quenching mixing holes 23 cooperate with each other to further improve the fuel-rich combustion performance. Specifically, the ignition performance of the nozzle 7 affects the uniformity of fuel distribution in the fuel-rich combustion area, and the quenching mixing holes shorten the residence time of the fuel gas in the high-temperature area by rapidly cooling it, thereby jointly suppressing the NOx generation path.

[0032] In one embodiment, a plurality of second quenching and mixing holes are provided circumferentially along the inner ring 3 of the flame tube, and the plurality of second quenching and mixing holes are located within an area having another nozzle 7. It should be noted that the two nozzles 7, as well as the second quenching and mixing holes and the first quenching and mixing holes 23, have the same functions and are not described here. Both the inner ring 3 of the flame tube and the outer ring 2 of the flame tube have an outer profile 21 and an inner profile 22. The outer profile 21 is the outer wall structure of the inner ring 3 of the flame tube and the outer ring 2 of the flame tube, and the inner profile 22 is the inner wall structure of the inner ring 3 of the flame tube and the outer ring 2 of the flame tube.

[0033] In one embodiment, a mounting base 24 is provided on the flame tube outer ring 2, and the electric nozzle 7 is mounted on the mounting base 24. The mounting base 24 connects the electric nozzle 7 to the cavity formed by the flame tube outer ring 2 and the flame tube inner ring 3. The electric nozzle 7 is fixedly connected to the flame tube outer ring 2 by the mounting base 24 to fix the electric nozzle 7 to the flame tube outer ring 2. It should be noted that there are two mounting bases 24, each provided on a corresponding flame tube outer ring 2. The two electric nozzles 7 are respectively provided on the corresponding mounting bases 24. Ignition is achieved by connecting the electric nozzle 7 and the mounting bases 24 to the cavity.

[0034] In one embodiment, it also includes a plurality of lean oil nozzles 4 and two rich oil nozzles 5. The plurality of lean oil nozzles 4 are connected to the corresponding lean oil combustion structure 11, and each rich oil nozzle 5 is respectively connected to the corresponding rich oil combustion structure 12. The multiple lean oil nozzles 4 are responsible for the linked flame ignition under a small state, and the combustion mode is lean oil combustion, which is mainly responsible for reducing emissions. It should be noted that the two rich oil nozzles 5 and the electric nozzle 7 are located in the same area or on the same cross section. In addition, because the rich oil main combustion zone is designed to be rich oil, the ignition and extinguishing performance is better, which can improve the ignition and extinguishing performance of the combustion chamber.

[0035] like Figure 6As shown, in one embodiment, multiple lean-fuel nozzles 4 include a nozzle stem 41, a secondary mold structure 42, and a nozzle main mold 43. The secondary mold structure 42 and the nozzle main mold 43 are respectively provided on the flame tube head 1. The nozzle stem 41 is connected to the lean-fuel combustion structure 11, and the channels it has are respectively connected to the secondary mold structure 42 and the nozzle main mold 43. The oil circuit design of the nozzle main mold 43 adopts a multi-point injection method, and its combustion mode is lean-fuel combustion, which is mainly responsible for reducing emissions.

[0036] like Figure 7 As shown, in one embodiment, the nozzle main mold 43 includes a main mold nozzle 431 and a main mold swirler 432. The main mold swirler 432 is arranged on the cylinder, and the cylinder is arranged on the lean fuel combustion structure 11. The main mold nozzle 431 is opened on the cylinder. The main mold swirler 432 can increase the main mold swirler 432 to form a stable central recirculation zone through strong swirl, extend the oil and gas mixing time, make the fuel evenly distributed, reduce the residence time in the local high-temperature zone, and inhibit NOx generation. The main mold nozzle 431 generates strong shear force through the swirl field of the main mold swirler 432, and combines with an air atomizing nozzle (such as a pressure swirl nozzle) to achieve efficient fuel crushing. The microscopic particle size distribution directly affects the combustion efficiency and pollutant generation.

[0037] In one embodiment, the secondary mold structure 42 includes a secondary mold nozzle 421 and a secondary mold air swirler 422. The secondary mold nozzle 421 is disposed on the lean burn structure 11 and connected to the oil circuit. The secondary mold air swirler 422 is sleeved within the oil circuit, one end of which is connected to the nozzle rod 41 and the other end to the secondary mold nozzle 421. When the primary mold swirler 432 and the secondary mold air swirler 422 work together, the secondary mold air swirler 422 is responsible for macro-mixing, while providing high-speed airflow to refine fuel particles. The secondary mold nozzle 421 is a pressure atomizing nozzle, primarily responsible for the cross-flame ignition under low-pressure conditions.

[0038] like Figure 8 As shown, in one embodiment, the two oil-rich nozzles 5 each include a fuel nozzle 51 and an oil-rich swirler 52. The fuel nozzle 51 is connected to the oil-rich combustion structure 12, and the oil-rich swirler 52 is sleeved on the fuel nozzle 51. The fuel nozzle 51 and the oil-rich swirler 52 are designed to be oil-rich in the main combustion zone, so the ignition and flameout performance are better, which can improve the ignition and flameout performance of the combustion chamber.

[0039] In one embodiment, a casing 6 is further included. The liner head 1, liner outer ring 2, and liner inner ring 3 are all located within the casing 6. Two electric nozzles 7 extend through the casing 6 to the corresponding areas of the liner outer ring 2. The casing 6 ensures stable operation of the combustion chamber under extreme operating conditions and is a core component that ensures the reliability of the hot end components of the aircraft engine.

[0040] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-pollution combustion chamber, characterized in that: include: A flame tube head (1), two electric nozzles (7), a flame tube outer ring (2) and a flame tube inner ring (3); the flame tube head (1) is arranged between the flame tube outer ring (2) and the flame tube inner ring (3) and is respectively connected to the flame tube outer ring (2) and the flame tube inner ring (3); a plurality of lean fuel combustion structures (11) and two rich fuel combustion structures (12) are provided in the circumferential direction of the flame tube head (1); the two electric nozzles (7) are respectively arranged at different positions of the flame tube outer ring (2), and each electric nozzle (7) is respectively in the same area as each corresponding rich fuel combustion structure (12).

2. The low-pollution combustion chamber according to claim 1, characterized in that: A plurality of first quenching and mixing holes (23) are provided in the circumferential direction of the flame tube outer ring (2), and the plurality of first quenching and mixing holes (23) are located in an area having one of the electric nozzles (7).

3. The low-pollution combustion chamber according to claim 1, characterized in that: A plurality of second quenching and mixing holes are provided in the circumferential direction of the flame tube inner ring (3), and the plurality of second quenching and mixing holes are located in an area having another of the electric nozzles (7).

4. The low-pollution combustion chamber according to claim 2, characterized in that: A mounting seat (24) is provided on the flame tube outer ring (2), and the electric nozzle (7) is provided on the mounting seat (24). The electric nozzle (7) is connected to a cavity formed by the flame tube outer ring (2) and the flame tube inner ring (3) through the mounting seat (24).

5. The low-pollution combustion chamber according to claim 1, characterized in that: It also includes a plurality of lean oil nozzles (4) and two rich oil nozzles (5), wherein the plurality of lean oil nozzles (4) are connected to the corresponding lean oil combustion structure (11), and each rich oil nozzle (5) is respectively connected to the corresponding rich oil combustion structure (12).

6. The low-pollution combustion chamber according to claim 5, characterized in that: The plurality of lean fuel nozzles (4) include a nozzle rod (41), a secondary mold structure (42) and a nozzle main mold (43), wherein the secondary mold structure (42) and the nozzle main mold (43) are respectively arranged on the flame tube head (1), and the nozzle rod (41) is connected to the lean fuel combustion structure (11) and has a channel that is respectively communicated with the secondary mold structure (42) and the nozzle main mold (43).

7. The low-pollution combustion chamber according to claim 6, characterized in that: The nozzle main mold (43) comprises a main mold nozzle (431) and a main mold swirler (432), wherein the main mold swirler (432) is arranged on a cylinder, and the cylinder is arranged on the lean fuel combustion structure (11), and the main mold nozzle (431) is opened on the cylinder.

8. The low-pollution combustion chamber according to claim 6, characterized in that: The sub-mold structure (42) includes a sub-mold nozzle (421) and a sub-mold air swirler (422), wherein the sub-mold nozzle (421) is arranged on the lean combustion structure (11), the sub-mold nozzle (421) is connected to an oil circuit, and the sub-mold air swirler (422) is sleeved on the oil circuit, the oil circuit is communicated with the nozzle rod (41), and the other end is connected to the sub-mold nozzle 421.

9. The low-pollution combustion chamber according to claim 5, characterized in that: The two oil-rich nozzles (5) include a fuel nozzle (51) and an oil-rich swirler (52). The fuel nozzle (51) is connected to the oil-rich combustion structure (12), and the oil-rich swirler (52) is sleeved on the fuel nozzle (51).

10. The low-pollution combustion chamber according to claim 1, characterized in that: It also includes a casing (6), wherein the flame tube head (1), the flame tube outer ring (2) and the flame tube inner ring (3) are all located in the casing (6), and the two electric nozzles (7) respectively pass through the casing (6) to the flame tube outer ring (2) in the corresponding area.

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