New fuel blending central staged combustor

Abstract

The present invention relates to the technical field of aeroengines, and provides a novel fuel mixing central staged combustor, which includes an outer ring and a diffuser, an oil rod nozzle structure, a first-stage pre-combustion stage, a second-stage pre-combustion stage, a main combustion stage, and a confinement structure arranged inside the outer ring; the first-stage pre-combustion stage, the second-stage pre-combustion stage, and the main combustion stage are sleeved in sequence along the radial direction; the oil rod nozzle structure is located inside the first-stage pre-combustion stage, the diffuser is located on the side of the first-stage pre-combustion stage, the second-stage pre-combustion stage, and the main combustion stage close to the outer ring air inlet, and a cooling cavity is formed between the confinement structure and the outer ring. The present invention adopts a two-stage axial pre-combustion stage structure, which has a better atomization effect than a single-stage axial pre-combustion stage, improves the layout of the combustor, optimizes the combustion performance and emission performance, and can achieve a wider blowout range and working range than the existing combustor.

Description

Technical Field

[0001] The present invention relates to the technical field of aeroengines, and particularly to a novel fuel mixing central staged combustor. Background Art

[0002] With the increasing attention of society to environmental pollution problems, the standards for pollutant emissions are becoming more and more stringent. The combustion of fossil fuels in power plants is the main cause of environmental air pollution and ozone layer depletion. Therefore, reducing the emission ratio of combustion exhaust gas in power plants and making the fuel burn more fully is one of the important ways to control environmental pollution. At the same time, the new generation of aeroengines in the future also puts forward new requirements for the combustion performance of the combustor. Achieving sufficient fuel-air mixing is a common technical challenge. Due to the high-temperature and low-pressure inlet parameters, compact size, and high reference speed of the main combustor, it is necessary to solve the fuel-air mixing problem under a wide range of incoming flow temperatures to achieve the purpose of efficient combustion and low pollution emissions.

[0003] Staged combustion refers to the use of two combustion zones to stage fuel and air simultaneously. Currently, the mainstream staged combustion modes at home and abroad are the following 4 types: central staged combustion mode, circumferential staged combustion mode, axial staged combustion mode, and radial staged combustion mode. Among them, the central staged structure is the current mainstream combustor structure of aeroengines.

[0004] The central staged combustor generally adopts a combustion organization mode of concentric stratified swirling flames, such as Figure 1 shown. The inner layer is the pilot stage 1, and a diffusion flame is applied, which can improve the combustion efficiency in the single flame state and play a role in stabilizing the flame under large operating conditions. The outer layer is the main combustion stage 3, which can ensure the combustion efficiency and low emission requirements in the double flame mode. Traditional swirlers 2 are provided in both the pilot stage 1 and the main combustion stage 3.

[0005] The traditional central staged structure combustor has the following deficiencies: 1. The new generation of main combustors has high requirements for mixing time and mixing distance, and the traditional central staged combustor structure cannot meet the requirements of space compactness; 2. The single-stage axial swirl mixing efficiency of the pilot stage 1 is low; 3. The structure of the main combustion stage 3 with blade injection is simple. Adopting blade injection can improve the head flow rate, but the effect is limited. Summary of the Invention

[0006] The present invention provides a novel fuel mixing central staged combustor to solve the problem of low single-stage axial swirl mixing efficiency in the prior art.

[0007] The present invention provides a novel fuel-blended central staged combustor, which includes an outer ring, and a diffuser, an oil rod nozzle structure, a first-stage pre-combustion stage, a second-stage pre-combustion stage, a main combustion stage, and a confinement domain structure arranged inside the outer ring; the first-stage pre-combustion stage, the second-stage pre-combustion stage, and the main combustion stage are sleeved along the radial direction in sequence; the oil rod nozzle structure is located inside the first-stage pre-combustion stage, the diffuser is located on one side of the first-stage pre-combustion stage, the second-stage pre-combustion stage, and the main combustion stage close to the air inlet of the outer ring, the confinement domain structure is located on one side of the first-stage pre-combustion stage, the second-stage pre-combustion stage, and the main combustion stage close to the air outlet of the outer ring, and a cooling cavity is formed between the confinement domain structure and the outer ring.

[0008] According to the novel fuel-blended central staged combustor provided by the present invention, the main combustion stage includes a main combustion stage sleeve, a plurality of SK-type swirlers, and a plurality of partitions. The main combustion stage sleeve is located outside the second-stage pre-combustion stage and forms an annular space with the second-stage pre-combustion stage. The partitions and the SK-type swirlers are arranged in the annular space. The plurality of partitions divide the annular space into a plurality of installation cavities. The plurality of SK-type swirlers are arranged in one-to-one correspondence with the plurality of installation cavities, and the SK-type swirlers are fixedly arranged in the corresponding installation cavities.

[0009] According to the novel fuel-blended central staged combustor provided by the present invention, each SK-type swirler is correspondingly provided with a first fuel injection hole and a second fuel injection hole. The first fuel injection hole is located upstream of the air flow direction of the SK-type swirler, and the second fuel injection hole is located downstream of the SK-type swirler.

[0010] According to the novel fuel-blended central staged combustor provided by the present invention, when the air flow inlet temperature of the main combustion stage is lower than a first preset value, fuel is injected through the first fuel injection hole; when the air flow inlet temperature of the main combustion stage is higher than the second preset value, fuel is injected through the second fuel injection hole; wherein, the second preset value is greater than the first preset value.

[0011] According to the novel fuel-blended central staged combustor provided by the present invention, the aspect ratio of the SK-type swirler is 1.08, and the blade thickness is 0.4 mm.

[0012] According to the novel fuel-blended central staged combustor provided by the present invention, the blade rotation directions of the swirlers in the first-stage pre-combustion stage and the second-stage pre-combustion stage are opposite.

[0013] A novel fuel blending central staged combustor provided by the present invention, the diffuser includes a pair of guide vanes, and the guide vanes divide the inner part of the outer ring into a first channel, a second channel, and a third channel arranged sequentially downward, and the first channel, the second channel, and the third channel respectively play a role in pressure expansion.

[0014] For a novel fuel blending central staged combustor provided by the present invention, the overall expansion angle of the diffuser is 68.286°, the expansion angle of the first channel is 17.574°, the expansion angle of the second channel is 56.7872°, and the expansion angle of the third channel is 6.0186°;

[0015] The sudden expansion gap of the diffuser is 15.1 mm to 17.3 mm, the inlet height of the diffuser is 27.4976 mm, and the sudden expansion gap ratio of the diffuser is 0.54 to 0.63.

[0016] The novel fuel blending central staged combustor provided by the present invention is provided with a first-stage pre-combustion stage and a second-stage pre-combustion stage, and adopts a double-stage axial pre-combustion stage structure, which has a better atomization effect than a single-stage axial pre-combustion stage, improves the layout of the combustor, optimizes the combustion performance and emission performance, and can achieve a wider ignition extinction range and working range than the existing combustor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 is a schematic structural diagram of the combustor head in the prior art;

[0019] Figure 2 is a schematic structural diagram of a novel fuel blending central staged combustor provided by the present invention;

[0020] Figure 3 is one of the schematic diagrams of the cooperation structure of the first-stage pre-combustion stage and the second-stage pre-combustion stage in a novel fuel blending central staged combustor provided by the present invention;

[0021] Figure 4 is another schematic diagram of the cooperation structure of the first-stage pre-combustion stage and the second-stage pre-combustion stage in a novel fuel blending central staged combustor provided by the present invention;

[0022] Figure 5 is one of the schematic diagrams of the structure of the main combustion stage in a novel fuel blending central staged combustor provided by the present invention;

[0023] Figure 6 This is the second structural schematic diagram of the main combustion stage in a novel fuel blending central staged combustor provided by the present invention;

[0024] Figure 7 This is the structural schematic diagram of the SK type swirler in a novel fuel blending central staged combustor provided by the present invention;

[0025] Figure 8 This is the structural schematic diagram of the diffuser in a novel fuel blending central staged combustor provided by the present invention;

[0026] Reference numerals: 1, pre - combustion stage; 2, swirler; 3, main combustion stage; 4, outer ring; 5, diffuser; 6, oil rod nozzle structure; 7, first - stage pre - combustion stage; 8, second - stage pre - combustion stage; 9, restriction domain structure; 10, first - stage pre - combustion stage sleeve; 11, first vane swirler; 12, second - stage pre - combustion stage sleeve; 13, second vane swirler; 14, main combustion stage sleeve; 15, SK type swirler; 16, partition; 17, guide vane; 18, first channel; 19, second channel; 20, third channel. Detailed implementation manners

[0027] The following further describes the implementation manners of the present invention in detail with reference to the drawings and embodiments. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0028] In the description of the embodiments of the present invention, it should be noted that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation to the embodiments of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0029] In the description of the embodiments of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "connected" and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific situations.

[0030] In the embodiments of the present invention, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the horizontal height of the first feature is less than that of the second feature.

[0031] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0032] The following Figures 1 to 8 describes the novel fuel-blending central staged combustor of the embodiments of the present invention, where Figure 1 is a schematic structural diagram of the combustor head in the prior art, Figure 2 is a schematic structural diagram of a novel fuel-blending central staged combustor provided by the present invention; Figure 3 is one of the schematic structural diagrams of the cooperation structure of the first-stage pre-combustion stage 7 and the second-stage pre-combustion stage 8 in a novel fuel-blending central staged combustor provided by the present invention; Figure 4 is another schematic structural diagram of the cooperation structure of the first-stage pre-combustion stage 7 and the second-stage pre-combustion stage 8 in a novel fuel-blending central staged combustor provided by the present invention; Figure 5 is one of the schematic structural diagrams of the main combustion stage 3 in a novel fuel-blending central staged combustor provided by the present invention; Figure 6 is another schematic structural diagram of the main combustion stage 3 in a novel fuel-blending central staged combustor provided by the present invention; Figure 7 is a schematic structural diagram of the SK type swirler 15 in a novel fuel-blending central staged combustor provided by the present invention; Figure 8 is a schematic structural diagram of the diffuser in a novel fuel-blending central staged combustor provided by the present invention.

[0033] Combined with Figure 1, The main combustion stage 3 and the pilot combustion stage 1, as the key structures of the central staged combustor, directly affect the combustion efficiency of aviation kerosene and the pollution emission results. The swirler is a structure that mixes the incoming air and fuel by forming a specific restricted domain at the head of the combustor. It can effectively improve the fuel mixing effect, enhance the combustion efficiency, and reduce pollutant emissions. The center is the pilot combustion stage 1, which uses a diffusion flame to ensure the combustion efficiency and flame stability under the idle condition (only the pilot combustion stage 1 is on, single flame); the outer periphery is the main combustion stage 3, which can ensure high combustion efficiency and low emissions under large operating conditions such as approach, climb, and takeoff (the main combustion stage 3 and the pilot combustion stage 1 work simultaneously, dual flames). However, the atomization and mixing effects of the traditional pilot combustion stage 1 and main combustion stage 3 structures are limited and cannot meet the requirements of the combustion performance of the new generation of engines. At the same time, backfire and spontaneous combustion are likely to occur. Therefore, it is necessary to innovate the swirler structure.

[0034] See Figure 2 , The novel fuel mixing central staged combustor according to the embodiment of the present invention includes an outer ring 4, and a diffuser 5, an oil rod nozzle structure 6, a first-stage pilot combustion stage 7, a second-stage pilot combustion stage 8, a main combustion stage 3, and a restricted domain structure 9 arranged inside the outer ring 4; the first-stage pilot combustion stage 7, the second-stage pilot combustion stage 8, and the main combustion stage 3 are sleeved in sequence along the radial direction; the oil rod nozzle structure 6 is located inside the first-stage pilot combustion stage 7, the diffuser 5 is located on the side of the first-stage pilot combustion stage 7, the second-stage pilot combustion stage 8, and the main combustion stage 3 close to the air inlet of the outer ring 4, and the restricted domain structure 9 is located on the side of the first-stage pilot combustion stage 7, the second-stage pilot combustion stage 8, and the main combustion stage 3 close to the air outlet of the outer ring 4. A cooling cavity is formed between the restricted domain structure 9 and the outer ring 4.

[0035] In the embodiment of the present invention, the first-stage pilot combustion stage 7 and the second-stage pilot combustion stage 8 constitute a two-stage axial pilot combustion stage structure. The incoming gas enters from the left head, is atomized through the shearing action of the two-stage blades, and then enters the inside of the combustor to mix with the kerosene sprayed by the oil rod nozzle structure 6. The atomization effect is better than that of the single-stage axial pilot combustion stage, improving the layout of the combustor, optimizing the combustion performance and emission performance, and achieving a wider ignition extinction range and working range than the existing combustor.

[0036] Combined with Figure 3 and Figure 4 , In some embodiments of the present invention, the first-stage pilot combustion stage 7 includes a first-stage pilot combustion stage sleeve 10 and a first vane swirler 11 arranged inside the first-stage pilot combustion stage sleeve 10, and the oil rod nozzle structure 6 is located inside the first vane swirler 11. The second-stage pilot combustion stage 8 includes a second-stage pilot combustion stage sleeve 12 sleeved outside the first-stage pilot combustion stage sleeve 10 and a second vane swirler 13 arranged between the first-stage pilot combustion stage sleeve 10 and the second-stage pilot combustion stage sleeve 12.

[0037] The length of the first-stage pre-combustion stage sleeve 10 is less than that of the second-stage pre-combustion stage sleeve 12. One end of the first-stage pre-combustion stage sleeve 10 close to the diffuser 5 is aligned with the second-stage pre-combustion stage sleeve 12, and the other end of the first-stage pre-combustion stage sleeve 10 away from the diffuser 5 is located inside the second-stage pre-combustion stage sleeve 12.

[0038] The first vane swirler 11 and the second vane swirler 13 have the structure of traditional vane swirlers.

[0039] Optionally, a reduced-diameter structure with a reduced inner diameter is provided in a partial section between the two ends of the first-stage pre-combustion stage sleeve 10 and the second-stage pre-combustion stage sleeve 12, and the ends of the first-stage pre-combustion stage sleeve 10 and the second-stage pre-combustion stage sleeve 12 away from the diffuser 5 are provided with a flared structure with a gradually increasing inner diameter.

[0040] Optionally, a limiting plate is provided on the outer side of the end of the second-stage pre-combustion stage sleeve 12 away from the diffuser 5, and the limiting plate is in limiting cooperation with the end of the main combustion stage 3 away from the diffuser 5. A stepped structure is formed between the main combustion stage 3 and the pre-combustion stage, which can separate the two jets of the main combustion stage 3 and the pre-combustion stage. The flame of the main combustion stage 3 is on the outside and the flame of the pre-combustion stage is on the inside, affecting the confluence position of the two airflows, thereby affecting the performance of the flow field, emissions, ignition, lean blowout, etc.

[0041] In some embodiments of the present invention, the vane swirl directions of the swirlers in the first-stage pre-combustion stage 7 and the second-stage pre-combustion stage 8 are opposite, that is, the vane swirl directions of the first vane swirler 11 and the second vane swirler 13 are opposite. For example, the swirl direction of the first vane swirler 11 is clockwise, and the swirl direction of the second vane swirler 13 is counterclockwise, or the swirl direction of the first vane swirler 11 is counterclockwise, and the swirl direction of the second vane swirler 13 is clockwise.

[0042] Optionally, the swirlers in the first-stage pre-combustion stage 7 and the second-stage pre-combustion stage 8 are arranged at one end of the first-stage pre-combustion stage 7 and the second-stage pre-combustion stage 8 close to the diffuser 5.

[0043] In some embodiments of the present invention, the main combustion stage 3 includes a main combustion stage sleeve 14, a plurality of SK-type swirlers 15, and a plurality of partition plates 16. The main combustion stage sleeve 14 is located outside the second-stage pre-combustion stage 8 and forms an annular interval with the second-stage pre-combustion stage 8. The partition plates 16 and the SK-type swirlers 15 are arranged in the annular interval. The plurality of partition plates 16 divide the annular interval inside the main combustion stage sleeve 14 into a plurality of installation cavities, and the plurality of SK-type swirlers 15 are arranged corresponding to the plurality of installation cavities one by one. The SK-type swirlers 15 are fixedly arranged in the corresponding installation cavities.

[0044] The SK-type swirler 15 includes either a left-handed blade or a right-handed blade with a twist angle of 180°, and has the advantages of simple structure, no mechanical stirring, continuous production, low operating cost, high mixing efficiency, etc.

[0045] Optionally, the SK type cyclone 15 uses right-handed blades, the length-diameter ratio L / D is 1.08, and the blade thickness N is 0.4 mm.

[0046] Optionally, an annular channel with a trapezoidal cross-section is formed between the main combustion stage sleeve 14 and the second-stage pre-combustion stage 8, and a plurality of SK type cyclones 15 and a plurality of partitions 16 are circumferentially arranged in the trapezoidal annular channel.

[0047] Optionally, 19 SK type cyclones 15 are provided.

[0048] Optionally, the length of the partition 16 is greater than the axial length of the SK type cyclone 15. By lengthening the restricted area of the pre-mixing channel of fuel and air, the atomization effect is enhanced, and at the same time, the backfire caused by the spontaneous combustion of kerosene is prevented.

[0049] In this embodiment, changing the main combustion stage 3 from a blade structure to a configuration with multiple SK type cyclones 15 can meet the technical requirements of efficient, stable, and low-resistance combustion in the engine combustion chamber. At the same time, the structure of the combustion chamber is made compact, the flow loss is reduced, and stable combustion is achieved.

[0050] In some embodiments of the present invention, each SK type cyclone 15 is correspondingly provided with two fuel injection holes, one of the fuel injection holes is located upstream of the SK type cyclone 15 in the air flow direction, and the other fuel injection hole is located downstream of the SK type cyclone 15.

[0051] The upstream of the air flow direction of the SK type cyclone 15 refers to the side close to the air flow inlet at the axial center of the SK type cyclone 15, and the downstream of the air flow direction of the SK type cyclone 15 refers to the side away from the air flow inlet at the axial center of the SK type cyclone 15.

[0052] Optionally, the oil path of the main combustion stage 3 is between the second-stage pre-combustion stage 8 and the main combustion stage 3, and the first fuel injection hole and the second fuel injection hole are communicated with the oil path of the main combustion stage 3.

[0053] The fuel injection method in the main combustion stage 3 is changed from blade injection to radial injection, and different injection holes are opened under different working conditions. After the fuel is ejected from the fuel injection holes of the SK type cyclone 15, it is mixed with the swirling air and jointly enters the pre-mixing channel of the main combustion stage 3, and then enters the combustion chamber for combustion.

[0054] In some embodiments of the present invention, when the air flow inlet temperature of the main combustion stage 3 is lower than the first preset value, the fuel is injected through the first fuel injection hole; when the air flow inlet temperature of the main combustion stage 3 is higher than the second preset value, the fuel is injected through the second fuel injection hole; wherein, the second preset value is greater than the first preset value.

[0055] Optionally, the first preset temperature is 830K, and the second preset temperature is 1150K.

[0056] In this embodiment, fuel is injected from the upstream or downstream of the SK-type swirler 15 according to the incoming flow temperature, shortening the fuel evaporation time. The SK-type swirler 15 can enhance the mixing of oil and gas and shorten the mixing time of oil and gas.

[0057] For the novel fuel mixing central staged combustor according to the embodiment of the present invention, the SK-type swirler 15 adopted mainly acts on the fluid by cutting and shearing, and at the same time has its own unique advantages, that is, simple operation, good mixing effect, easy installation of nozzles, convenient fuel injection, small volume and light weight, which can leave more space for the mixing of air and kerosene and reduce the head weight.

[0058] Due to the auto-ignition problem of hydrocarbon fuels under high-temperature and high-pressure conditions, it is necessary to ensure that the residence time of fuel in the premixing channel is shorter than the theoretical auto-ignition time. From a safety perspective, a certain time margin needs to be left. Due to the strong mixing effect, the main combustion stage 3 equipped with the SK-type swirler 15 has a longer premixing channel than the traditional main combustion stage, and the combustion is more stable and the combustion efficiency is higher.

[0059] In some embodiments of the present invention, the diffuser 5 includes guide vanes 17. There are two relatively arranged guide vanes 17, and the two guide vanes 17 are arranged vertically. The guide vanes 17 divide the position inside the outer ring 4 near the air inlet into a first channel 18, a second channel 19 and a third channel 20 arranged in sequence downward, and the first channel 18, the second channel 19 and the third channel 20 respectively play a diffusing role.

[0060] The diffuser 5 of this embodiment includes a multi-channel pre-diffuser and a sudden expansion area. Different from the single-channel sudden expansion diffuser, the rear end of the pre-diffuser does not extend into the sudden expansion area. The air flow first enters the pre-diffuser and is divided into three by the built-in guide vanes 17 and enters three channels equivalent to small diffusers to decelerate and diffuse respectively. The guide vanes 17 can guide the air flow to the inner and outer ring channels and the flame tube respectively, reducing the turning angle required for the sudden expansion area of the air flow.

[0061] Optionally, the overall expansion angle α of the diffuser 5 is 68.286°, the expansion angle of the first channel 18 is 17.574°, the expansion angle of the second channel 19 is 56.7872°, and the expansion angle of the third channel 20 is 6.0186°; the sudden expansion gap (the distance from the outlet of the diffuser 5 to the inlet of the flame tube) of the diffuser 5 is 15.1 mm to 17.3 mm, the inlet height of the diffuser 5 (the distance between two first guide vanes at the air inlet end) is 27.4976 mm, and the sudden expansion gap ratio ε of the diffuser 5 (defined as ε = sudden expansion gap / inlet height of the diffuser 5) is 0.54 to 0.63.

[0062] The novel fuel-blending central staging combustor provided by the present invention utilizes the diffuser 5 to decelerate and pressurize, and the strong swirling flow effect of the head structure to reasonably distribute the incoming air volume, enhance the atomization effect, improve the flow rate of the combustor head, and shorten the residence time. At the same time, due to the reasonable structure, the layout of the combustor is improved, making the combustor more compact, optimizing the combustion performance and emission performance, and achieving a wider ignition and extinction range and working range than the existing combustors.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A new type of fuel-blended center-staged combustor, characterized in that, It includes an outer ring, and a diffuser, an oil rod nozzle structure, a first-stage pre-combustion stage, a second-stage pre-combustion stage, a main combustion stage, and a restricted domain structure arranged inside the outer ring; the first-stage pre-combustion stage, the second-stage pre-combustion stage, and the main combustion stage are sleeved along the radial direction in sequence; the oil rod nozzle structure is located inside the first-stage pre-combustion stage, the diffuser is located on the side of the first-stage pre-combustion stage, the second-stage pre-combustion stage, and the main combustion stage close to the outer ring air inlet, the restricted domain structure is located on the side of the first-stage pre-combustion stage, the second-stage pre-combustion stage, and the main combustion stage close to the outer ring air outlet, and a cooling cavity is formed between the restricted domain structure and the outer ring; the main combustion stage includes a main combustion stage sleeve, a plurality of SK-type swirlers, and a plurality of partitions, the main combustion stage sleeve is located outside the second-stage pre-combustion stage and forms an annular space with the second-stage pre-combustion stage, the partitions and the SK-type swirlers are arranged in the annular space, the plurality of partitions divide the annular space into a plurality of installation cavities, the plurality of SK-type swirlers are arranged corresponding to the plurality of installation cavities one by one, and the SK-type swirlers are fixedly arranged in the corresponding installation cavities; the rotation directions of the blades of the swirlers in the first-stage pre-combustion stage and the second-stage pre-combustion stage are opposite; Each of the SK-type swirlers is correspondingly provided with a first fuel injection hole and a second fuel injection hole, the first fuel injection hole is located upstream of the air flow direction of the SK-type swirler, and the second fuel injection hole is located downstream of the SK-type swirler; when the air flow inlet temperature of the main combustion stage is lower than a first preset value, fuel is injected through the first fuel injection hole; when the air flow inlet temperature of the main combustion stage is higher than a second preset value, fuel is injected through the second fuel injection hole; wherein, the second preset value is greater than the first preset value.

2. The novel fuel blending central staged combustor according to claim 1, wherein The aspect ratio of the SK-type swirler is 1.08, and the blade thickness is 0.4 mm.

3. The novel fuel blending central staged combustor according to claim 1, wherein The diffuser includes a pair of guide vanes, and the guide vanes divide the inner part of the outer ring into a first channel, a second channel, and a third channel arranged successively downward, and the first channel, the second channel, and the third channel respectively play a role in pressure expansion.

4. The novel fuel blending central staged combustor according to claim 3, wherein The overall expansion angle of the diffuser is 68.286°, the expansion angle of the first channel is 17.574°, the expansion angle of the second channel is 56.7872°, and the expansion angle of the third channel is 6.0186°; The sudden expansion gap of the diffuser is 15.1 mm to 17.3 mm, the inlet height of the diffuser is 27.4976 mm, and the sudden expansion gap ratio of the diffuser is 0.54 to 0.63.

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