A gas turbine wide range hydrogen blended low emission fuel nozzle

Abstract

The application discloses a kind of gas turbine wide-range hydrogen-doped low-emission fuel nozzles, belong to gas turbine technical field, the nozzle includes outer ring pipe and is arranged in outer ring pipe inside for transporting fuel center fuel supply pipe, air flow passage is formed between outer ring pipe and center fuel supply pipe, center fuel supply pipe includes pipeline main body and mixing guide section, pipeline main body outer wall is equipped with vortex generator and the fuel injection hole being communicated with pipeline main body inside, fuel injection hole includes vortex generator rear fuel injection hole located vortex generator directly behind and vortex generator interval fuel injection hole located between adjacent vortex generator, vortex generator, vortex generator rear fuel injection hole, vortex generator interval fuel injection hole and mixing guide section are cooperatively arranged, for improving fuel jet penetration ability, vortex generator rear air disturbance intensity and center fuel supply pipe tail backflow zone distribution.The nozzle of the application improves the mixing uniformity under wide-range hydrogen-doped condition, fuel adaptability.

Description

Technical Field

[0001] This invention belongs to the field of gas turbine technology, and specifically relates to a nozzle for a gas turbine with a wide range of hydrogen-blended, low-emission fuels. Background Technology

[0002] Currently, the main combustion organization methods for hydrogen fuel in gas turbines include diffusion combustion and premixed combustion. While diffusion combustion offers strong combustion stability and resistance to backfire, it creates localized high-temperature zones, leading to higher nitrogen oxide emissions. Premixed combustion, although effective in reducing peak flame temperature and nitrogen oxide emissions, suffers from insufficient hydrogen density compared to natural gas, resulting in inadequate jet penetration and difficulty in achieving rapid and uniform mixing of fuel and air within a limited mixing distance. Insufficient mixing at the nozzle exit can easily lead to uneven combustion temperature distribution, localized hot spots, and increased nitrogen oxide emissions.

[0003] From an engineering application perspective, the transition of gas turbines from traditional natural gas to pure hydrogen fuel is typically difficult to achieve in one step. Instead, it requires a gradual transition from low to high hydrogen blending ratios to pure hydrogen combustion. During this process, fuel characteristics undergo significant changes. Existing fuel nozzles are mostly designed for specific hydrogen blending ratios and can achieve some degree of premixing between fuel and air. However, when the hydrogen blending ratio changes significantly, the mixing of air and fuel within the nozzle also changes, resulting in substantial differences in blending effects under different operating conditions.

[0004] For example, invention application CN118310042A discloses a premixed nozzle for a combustion chamber of a hydrogen fuel gas turbine, comprising: a film gas development channel, a fuel-air rapid mixing conduit, and a detachable nozzle lip edge; the fuel-air rapid mixing conduit is located at the center of the film gas development channel, and utilizes the gap between the two to rapidly develop an annular film gas to prevent backfire, thereby improving the safety of the combustion chamber nozzle; the detachable nozzle lip edge is located on one side of the fuel-air rapid mixing conduit, and is formed by a combination of a detachable collar with an inverted conical hole and a conical nozzle lip edge fixed on the nozzle, used to flexibly adjust the size of the local reaction zone according to the flow field organization requirements, thereby controlling the rise height of the reaction zone and suppressing thermoacoustic oscillations.

[0005] For example, invention application CN120777589A discloses a staged premixed array microtube combustion chamber, including a head flange, a tail connecting plate, a pre-combustion pipeline, an igniter, array microtubes, and a gas collection shell. The head flange is provided with multiple fuel inlets; the tail connecting plate is arranged axially opposite to the head flange; the pre-combustion pipeline passes through the head flange and the tail connecting plate, and a pre-combustion nozzle is provided downstream of the pre-combustion pipeline at the tail connecting plate; the igniter is located at the tail connecting plate; the array microtubes include multi-stage main combustion pipelines, and a main combustion nozzle is provided downstream of the multi-stage main combustion pipelines at the tail connecting plate; the gas collection shell is provided with multiple gas collection chambers, which are respectively connected to multiple fuel inlets and multiple gas collection chambers are respectively connected to the multi-stage main combustion pipelines. Summary of the Invention

[0006] The purpose of this invention is to provide a nozzle for gas turbines with a wide range of hydrogen blending and low emission fuels. By coordinating the arrangement of a vortex generator, a fuel injection port behind the vortex generator, a fuel injection port between the vortex generators, and a blending guide section, the nozzle can adapt to various fuel compositions, including natural gas, low-proportion hydrogen-blended fuels, medium-to-high-proportion hydrogen-blended fuels, and pure hydrogen fuels. It achieves rapid and uniform blending of fuel and air within a limited blending distance, improves the blending uniformity at the nozzle outlet, and reduces the risks of localized fuel enrichment, localized high temperatures, and nitrogen oxide emissions, thereby meeting the requirements of gas turbines for wide-range hydrogen blending, low emissions, and stable combustion operation.

[0007] This invention provides a nozzle for a gas turbine with a wide range of hydrogen-blended, low-emission fuel. The nozzle includes an outer ring pipe and a central fuel supply pipe disposed inside the outer ring pipe for delivering fuel. An air flow channel is formed between the outer ring pipe and the central fuel supply pipe. The central fuel supply pipe includes a main pipe body and a mixing guide section. A vortex generator and a fuel injection hole connected to the inside of the main pipe body are provided on the outer wall of the main pipe body. The fuel injection hole includes a vortex generator rear fuel injection hole located directly behind the vortex generator and an inter-vortex generator fuel injection hole located between adjacent vortex generators. The vortex generator, the vortex generator rear fuel injection hole, the inter-vortex generator fuel injection hole, and the mixing guide section are arranged in coordination to improve the fuel jet penetration capability, the air disturbance intensity behind the vortex generator, and the distribution of the recirculation zone at the tail of the central fuel supply pipe.

[0008] Fuel enters the central fuel supply pipe through the front opening of the main pipe body and is transported along the inside of the main pipe body. It is injected from the fuel injection hole behind the vortex generator into the air flow channel between the outer ring pipe and the central fuel supply pipe. At the same time, when the main airflow passes through the vortex generator axially, the vortex generator forms a local low-speed zone behind it, which enhances the radial penetration depth of the fuel injected from the fuel injection hole behind the vortex generator. On the other hand, the vortex generator can induce the formation of vortex structure behind it, which enhances the mixing of fuel and air and improves the overall mixing uniformity within a limited mixing distance.

[0009] Specifically, the front opening of the main body of the pipeline is the air inlet of the nozzle.

[0010] Furthermore, the inner diameter of the outer ring pipe and the outer diameter of the central fuel supply pipe satisfy the following: ; in, The inner diameter of the outer ring pipe. The outer diameter of the central fuel supply pipe is defined as the outer diameter of the outer ring pipe, and the inner diameter of the outer ring pipe is limited to the range of 10 mm to 100 mm. By limiting the inner diameter of the outer ring pipe, the issues of manufacturing and processing costs, combustion stability, and mixing ability can be effectively balanced. When the inner diameter of the outer ring pipe is too small, the manufacturing cost increases significantly. When the inner diameter of the outer ring pipe is too large, it will increase the risk of backfire in the nozzle combustion and is not conducive to fuel mixing.

[0011] Furthermore, the axial distance from the fuel injection orifice axis to the outlet interface of the outer ring pipe is the effective mixing length, and the effective mixing length satisfies the following relationship with the inner diameter of the outer ring pipe: ; in, For effective mixing length; This is the inner diameter of the outer ring pipe.

[0012] By limiting the effective mixing length range, sufficient development distance can be provided for the mixing of fuel and air within the nozzle, while avoiding excessive nozzle axial length which would lead to increased flow losses and hinder the compact design of the gas turbine.

[0013] Furthermore, the number of vortex generators is between 2 and 6, and the number of vortex generators is the same as the number of fuel injection holes behind the vortex generators and the number of fuel injection holes between the vortex generators; By placing the fuel injection port behind the vortex generator directly behind the vortex generator, when the fuel is ejected through the fuel injection port behind the vortex generator, it can directly enter the low-speed zone formed behind the vortex generator. The radial jet depth is deep, mainly providing fuel to the outer peripheral area near the outer ring pipe. By placing the fuel injection holes between the vortex generators, the fuel is injected through the fuel injection holes between the vortex generators and directly enters the air mainstream area between the adjacent vortex generators and is transported to the rear. The jet depth is shallow, mainly providing fuel to the inner circumferential area near the central fuel supply pipe. By coordinating the arrangement of the vortex generator, the fuel injection holes behind the vortex generator, and the fuel injection holes between the vortex generators, the fuel distribution in the radial direction is made more uniform, improving the overall mixing uniformity at the nozzle outlet and thus enhancing the nozzle's wide range of fuel adaptability.

[0014] Furthermore, the diameters of the fuel injection holes behind the vortex generator and the fuel injection holes between the vortex generators respectively satisfy the following conditions: ; in, The diameter of the fuel injection port behind the vortex generator; The diameter of the fuel injection hole between the vortex generators.

[0015] Furthermore, the axial relative distance between the fuel injection port behind the vortex generator and the vortex generator. The diameter of the fuel injection port behind the vortex generator The following conditions must be met: .

[0016] Furthermore, the vortex generator adopts one of the following shapes: tetrahedral, wedge-shaped, triangular pyramidal, trapezoidal protrusions or guide vanes, to form a local low-speed zone and a disturbance vortex structure behind the vortex generator.

[0017] Preferably, the vortex generator adopts a tetrahedral structure, which is defined by the height of the vortex generator, the inclination angle of the leading edge surface, and the circumferential characteristic width. The height is the radial protrusion height of the vortex generator relative to the outer wall of the pipeline body, the inclination angle α of the leading edge surface is the angle between the leading edge surface of the vortex generator and the tangential direction of the outer wall of the pipeline body, and the circumferential characteristic width is used to characterize the maximum windward width of the vortex generator. The height, leading edge inclination angle, and circumferential characteristic width of the vortex generator satisfy the following relationship: ; in, The height of the vortex generator; The inclination angle of the leading edge surface; The width of the circumferential feature; The inner diameter of the outer ring pipe; The outer diameter of the central fuel supply pipe.

[0018] By synergistically limiting the dimensions of the vortex generator's height, leading edge inclination angle, and circumferential characteristic width, a balance can be achieved between enhancing the fuel jet penetration depth, increasing the intensity of air disturbance and pressure drop behind the vortex generator, thereby promoting rapid and uniform mixing of fuel and air within a limited mixing distance.

[0019] Furthermore, the mixing guide section includes a straight section for maintaining the radial penetration effect of the fuel jet and an inclined transition section for reducing flow separation and recirculation caused by abrupt changes at the tail of the central fuel supply pipe; The inclined transition section includes a smooth curve type inclined transition section and an approximately straight line type inclined transition section. The outer contour of the smooth curve type inclined transition section includes an elliptical arc type, a polynomial curve type, or a spline curve type.

[0020] Preferably, the inclined transition section is a smooth curved inclined transition section. When the outer contour of the smooth curved inclined transition section is an elliptical arc, the coordinate origin is defined with the center of the end of the straight section as the origin, the axial downstream direction of the nozzle as the z-axis, and the radial direction of the nozzle as the r-axis. The curve equation of the inclined transition section satisfies: ; Where z and r are the coordinates of the equation of the control smooth curve, respectively; The axial length of the smooth, curved, inclined transition section; The outer diameter of the central fuel supply pipe.

[0021] Preferably, the inclined transition section is an approximately straight inclined transition section, comprising a straight contraction section and an end arc transition section. The end arc transition section is tangentially connected to the straight contraction section to avoid sharp corners or geometric abrupt changes at the end of the inclined transition section, thereby reducing the risk of local flow separation and enhanced backflow. The axial length of the approximately straight inclined transition section is greater than twice the outer diameter of the central fuel supply pipe to prevent the inclined transition section from being too short, which would result in excessively rapid shape contraction and thus reduce the risk of large-scale backflow zones and flow separation at the tail end. The radius of the end arc transition section... satisfy: By adjusting the radius of the end arc transition section, the probability of local sharp corners and flow separation can be reduced.

[0022] The beneficial effects of this invention are: The present invention provides a nozzle for a gas turbine with a wide range of hydrogen-blended low-emission fuel. By coordinating the arrangement of the vortex generator with the fuel injection holes behind the vortex generator and the fuel injection holes between the vortex generators, the fuel jet penetration capability and radial fuel distribution uniformity are improved. At the same time, the tail recirculation zone is controlled by the blending guide section. Therefore, the blending uniformity and fuel adaptability under a wide range of hydrogen blending conditions can be improved. Attached Figure Description

[0023] Figure 1 A three-dimensional structural schematic diagram of the nozzle for a gas turbine with a wide range of hydrogen-blended low-emission fuels provided in an embodiment of the present invention; Figure 2 A three-dimensional structural schematic diagram of the central combustion pipe of the nozzle for a gas turbine with a wide range of hydrogen-blended low-emission fuels provided in an embodiment of the present invention; Figure 3 A schematic diagram of the mixing principle of a wide-range hydrogen-doped low-emission nozzle provided in an embodiment of the present invention, based on a schematic cross-section of the fuel injection hole behind the vortex generator ( Figure 3 (a) is a schematic diagram of the cross-section of the fuel injection holes between vortex generators. Figure 3 (b) in the middle); Figure 4 A cross-sectional view of the nozzle for a gas turbine with a wide range of hydrogen-blended low-emission fuels provided in an embodiment of the present invention; Figure 5 A partial schematic diagram of the central combustion pipe of the nozzle for a gas turbine with a wide range of hydrogen-blended low-emission fuels provided in an embodiment of the present invention; Figure 6 A partial cross-sectional view of the vortex generator and central fuel supply pipe of the nozzle for a gas turbine with a wide range of hydrogen-blended low-emission fuels provided in an embodiment of the present invention; Figure 7 This is a schematic diagram illustrating the structural form and dimensional parameters of the blended flow guiding section provided in an embodiment of the present invention, including a blended flow guiding section with a smooth curved inclined transition section (elliptical arc type). Figure 7 (a) of the text, is a blending guide section with an approximately straight inclined transition section. Figure 7 (b) in the middle); Figure 8 The ablation test results of the nozzle for a gas turbine with a wide range of hydrogen-blended low-emission fuels provided in this embodiment of the invention are shown in the figure. Under pure hydrogen conditions, the hydrogen mass fraction distribution at the nozzle outlet cross-section during actual operation of the complete nozzle is shown. Figure 8 In (a) of this structure, when the vortex generator is removed ( Figure 8 In (b) of the above structure, when the fuel injection port behind the vortex generator is removed ( Figure 8 (c) of the structure, when the fuel injection holes between the vortex generators are removed ( Figure 8 (d) in the middle); Figure 9 This is a schematic diagram illustrating the variation of the mixing degree with the axial direction of the nozzle for a gas turbine with a wide range of hydrogen-blended low-emission fuel provided in an embodiment of the present invention under different structural conditions and different hydrogen blending ratios.

[0024] Reference numerals in the attached diagram: 1. Outer ring pipe; 2. Central fuel supply pipe; 3. Main body of the pipeline; 4. Vortex generator; 5. Fuel injection orifice; 5a. Fuel injection orifice behind the vortex generator; 5b. Fuel injection orifice between the vortex generators; 6. Mixing guide section. Detailed Implementation

[0025] like Figure 1 , Figure 2As shown, a nozzle for a gas turbine with a wide range of hydrogen-blended low-emission fuel is disclosed. The nozzle includes an outer ring pipe 1 and a central fuel supply pipe 2 disposed inside the outer ring pipe 1 for transporting fuel. An air flow channel is formed between the outer ring pipe 1 and the central fuel supply pipe 2. The central fuel supply pipe 2 includes a pipe body 3 and a mixing guide section 6. A vortex generator 4 and a fuel injection hole 5 connected to the inside of the pipe body 3 are provided on the outer wall of the pipe body 3. The fuel injection hole 5 includes a vortex generator rear fuel injection hole 5a located directly behind the vortex generator 4 and an inter-vortex generator fuel injection hole 5b located between adjacent vortex generators 4. The vortex generator 4, the vortex generator rear fuel injection hole 5a, the inter-vortex generator fuel injection hole 5b and the mixing guide section 6 are arranged in coordination to improve the fuel jet penetration capability, the air disturbance intensity behind the vortex generator 4 and the distribution of the tail recirculation zone of the central fuel supply pipe 2.

[0026] like Figure 3 As shown, the cross-section of fuel injection port 5a behind the vortex generator is shown. Figure 3 (a) and the fuel injection port 5b section between the vortex generator ( Figure 3 The mixing principle of the wide-range hydrogen-doped low-emission nozzle is demonstrated in two sections (b).

[0027] Specifically, fuel enters the central fuel supply pipe 2 through the front opening of the main pipe body 3 and is transported along the inside of the main pipe body 3. It is injected from the fuel injection hole 5a behind the vortex generator and the fuel injection hole 5b between the vortex generator into the air flow channel between the outer ring pipe 1 and the central fuel supply pipe 2. At the same time, when the main airflow passes through the vortex generator 4 axially, the vortex generator 4 forms a local low-speed zone behind it, which enhances the radial penetration depth of the fuel injected from the fuel injection hole 5a behind the vortex generator. On the other hand, it can induce the formation of a vortex structure behind it, which enhances the mixing of fuel and air and improves the overall mixing uniformity within a limited mixing distance.

[0028] like Figure 4 As shown, in this embodiment, the inner diameter of the outer ring pipe 1 of the nozzle for the gas turbine with wide-range hydrogen-blended low-emission fuel is 25 mm, and the outer diameter of the central fuel supply pipe 2 is 15 mm. The inner diameter of the outer ring pipe 1 and the outer diameter of the central fuel supply pipe 2 satisfy the following: ; in, The inner diameter of outer ring pipe 1 The outer diameter of the central fuel supply pipe 2.

[0029] By limiting the inner diameter of the outer ring pipe 1, the issues of manufacturing and processing costs, combustion stability, and mixing ability can be effectively balanced. When the inner diameter of the outer ring pipe 1 is too small, the manufacturing cost increases significantly. When the inner diameter of the outer ring pipe 1 is too large, it will increase the risk of backfire in the nozzle combustion and is not conducive to fuel mixing.

[0030] In this embodiment, the effective mixing length of the nozzle for the gas turbine with wide-range hydrogen blending and low emission fuel is 250 mm. The effective mixing length and the inner diameter of the outer ring pipe satisfy the following: ; in, For effective mixing length; The inner diameter of the outer ring pipe 1.

[0031] By limiting the effective mixing length range, sufficient development distance can be provided for the mixing of fuel and air within the nozzle, while avoiding excessive nozzle axial length which would lead to increased flow losses and hinder the compact design of the gas turbine.

[0032] In this embodiment, the number of vortex generators 4 in the nozzle for the gas turbine with wide-range hydrogen-blended low-emission fuel is the same as the number of fuel injection holes 5a behind the vortex generator and the number of fuel injection holes 5b between the vortex generators, which is 4 in total. By coordinating the vortex generators 4 with the two types of fuel injection holes 5, the fuel is distributed more evenly in the radial direction, improving the overall mixing uniformity at the nozzle outlet, thereby improving the nozzle's wide-range fuel adaptability.

[0033] like Figure 5 , 6 As shown, in this embodiment, the diameter of the fuel injection hole 5a behind the vortex generator and the fuel injection hole 5b between the vortex generators is 1 mm, and the axial relative distance between the fuel injection hole 5a behind the vortex generator and the vortex generator 4 is 1.5 mm; and the height, leading edge inclination angle, and circumferential characteristic width of the vortex generator 4 are 3 mm, 45°, and 5 mm, respectively, and satisfy the following relationship: ; in, The height of vortex generator 4; The inclination angle of the leading edge surface of vortex generator 4; The circumferential characteristic width of vortex generator 4; The inner diameter of the outer ring pipe 1; The outer diameter of the central fuel supply pipe 2.

[0034] By synergistically limiting the dimensions of the height, leading edge inclination angle, and circumferential characteristic width of the vortex generator 4, a balance can be achieved between enhancing the fuel jet penetration depth, increasing the intensity of air disturbance and pressure loss behind the vortex generator 4, thereby promoting rapid and uniform mixing of fuel and air within a limited mixing distance.

[0035] like Figure 7As shown, the mixing guide section 6 includes a straight section for maintaining the radial penetration effect of the fuel jet and an inclined transition section for reducing flow separation and recirculation caused by abrupt changes at the tail of the central fuel supply pipe 2. Based on the inclined transition section, it is divided into a smooth curve type and an approximately straight line type. The outer contour of the smooth curve type inclined transition section can be an elliptical arc (e.g., ...). Figure 7 (a) ), polynomial curve type, spline curve type, or other curve forms that can achieve a smooth contraction transition, the approximately straight-line inclined transition segment includes a straight contraction segment and an end arc transition segment (such as Figure 7 (b)). In this embodiment, the mixing and guiding section 6 is actually an elliptical arc-shaped smooth curve inclined transition section.

[0036] like Figure 8 The diagram shows the ablation test results of the nozzle for the gas turbine with wide-range hydrogen-blended low-emission fuel provided in this embodiment. Under pure hydrogen conditions, the hydrogen mass fraction distribution at the nozzle outlet cross-section during actual operation of the complete nozzle structure is shown. The synergistic effect of the vortex generator 4, the fuel injection hole 5a behind the vortex generator, and the fuel injection hole 5b between the vortex generators allows fuel to replenish the outer and inner peripheral regions of the airflow channel (e.g., ...). Figure 8 (a)); After removing the vortex generator 4 from this structure, the fuel jet lacks the auxiliary effect of the local low-speed zone and the disturbance vortex structure, and the hydrogen is mainly concentrated in the inner peripheral region near the central combustion pipe 2 (e.g., Figure 8 (b)); After removing the fuel injection hole 5a behind the vortex generator based on this structure, the fuel supply in the outer peripheral region near the outer ring pipe 1 is insufficient, and a significant hydrogen-deficient zone appears in the outlet section (e.g. Figure 8 (c)); After removing the fuel injection hole 5b between the vortex generators based on this structure, the inner circumferential region near the central fuel supply pipe 2 is insufficiently fueled, and a central hydrogen-deficient zone appears at the outlet section (e.g. Figure 8 (d) in the middle.

[0037] The above ablation results indicate that the vortex generator 4, the fuel injection hole 5a behind the vortex generator, and the fuel injection hole 5b between the vortex generators are all key structures for improving the mixing uniformity. The synergistic effect of the three can effectively improve the hydrogen mass fraction distribution at the outlet section and improve the fuel-air mixing uniformity within a limited mixing distance.

[0038] like Figure 9As shown, the nozzle for the gas turbine wide-range hydrogen-blended low-emission fuel provided in this embodiment exhibits the variation of mixing degree with axial direction under different hydrogen blending ratios, after removing the vortex generator 4, the fuel injection hole 5a behind the vortex generator, and the fuel injection hole 5b between the vortex generators, based on the complete nozzle structure. It can be seen that the complete structure of this invention maintains the highest mixing degree under 0%, 30%, 60%, and 100% hydrogen blending conditions, with minimal fluctuations with varying hydrogen blending ratios. Conversely, any geometric mixing degree lacking the coordinated arrangement of this invention significantly decreases, and under the same structure, the fluctuation range with varying hydrogen blending ratios is generally larger.

[0039] Therefore, this invention not only improves the blending uniformity under single fuel conditions, but also maintains relatively stable blending performance under natural gas, low-proportion hydrogen blending, medium-high proportion hydrogen blending and pure hydrogen conditions, thereby improving the nozzle's adaptability to a wide range of hydrogen-blended fuels.

Claims

1. A nozzle for a gas turbine with a wide range of hydrogen-blended, low-emission fuels, the nozzle comprising an outer ring pipe and a central combustion supply pipe disposed inside the outer ring pipe for delivering fuel, wherein an airflow channel is formed between the outer ring pipe and the central combustion supply pipe, characterized in that, The central fuel supply pipe includes a main pipe body and a mixing guide section. The outer wall of the main pipe body is provided with a vortex generator and fuel injection holes that connect to the inside of the main pipe body. The fuel injection holes include a fuel injection hole located directly behind the vortex generator and a fuel injection hole located between adjacent vortex generators. The vortex generator, the fuel injection hole behind the vortex generator, the fuel injection hole between the vortex generators, and the mixing guide section are arranged in coordination to improve the fuel jet penetration capability, the air disturbance intensity behind the vortex generator, and the distribution of the recirculation zone at the tail of the central fuel supply pipe.

2. The nozzle according to claim 1, characterized in that, The inner diameter of the outer ring pipe is limited to the range of 10 mm to 100 mm, and the inner diameter of the outer ring pipe and the outer diameter of the central fuel supply pipe satisfy the following: ； in, The inner diameter of the outer ring pipe. The outer diameter of the central fuel supply pipe.

3. The nozzle according to claim 1, characterized in that, The axial distance from the fuel injection orifice axis to the outlet interface of the outer ring pipe is taken as the effective mixing length, and the effective mixing length satisfies the following relationship with the inner diameter of the outer ring pipe: ； in, For effective mixing length; This is the inner diameter of the outer ring pipe.

4. The nozzle according to claim 1, characterized in that, The diameters of the fuel injection holes behind the vortex generator and the fuel injection holes between the vortex generators respectively satisfy the following conditions: ； in, The diameter of the fuel injection port behind the vortex generator; The diameter of the fuel injection holes between the vortex generators; The axial relative distance between the fuel injection port behind the vortex generator and the vortex generator. The diameter of the fuel injection port behind the vortex generator The following conditions must be met: .

5. The nozzle according to claim 1, characterized in that, The number of vortex generators is the same as the number of fuel injection holes behind the vortex generators and the number of fuel injection holes between the vortex generators.

6. The nozzle according to claim 1, characterized in that, The vortex generator adopts one of the following shapes: tetrahedral, wedge-shaped, triangular pyramidal, trapezoidal protrusions or guide vanes, to form a local low-speed zone and a disturbance vortex structure behind the vortex generator.

7. The nozzle according to claim 6, characterized in that, The vortex generator adopts a tetrahedral structure, which is defined by the height of the vortex generator, the inclination angle of the leading edge surface, and the circumferential characteristic width. The height is the radial protrusion height of the vortex generator relative to the outer wall of the pipeline body, the inclination angle α of the leading edge surface is the angle between the leading edge surface of the vortex generator and the tangential direction of the outer wall of the pipeline body, and the circumferential characteristic width is used to characterize the maximum windward width of the vortex generator on the outer wall of the pipeline body. The height, leading edge inclination angle, and circumferential characteristic width of the vortex generator satisfy the following relationship: ； in, The height of the vortex generator; The inclination angle of the leading edge surface; The width of the circumferential feature; The inner diameter of the outer ring pipe; The outer diameter of the central fuel supply pipe.

8. The nozzle according to claim 1, characterized in that, The mixing and guiding section includes a straight section for maintaining the radial penetration effect of the fuel jet and an inclined transition section for reducing flow separation and recirculation caused by abrupt changes at the tail of the central fuel supply pipe. The inclined transition section includes a smooth curve type inclined transition section and an approximately straight line type inclined transition section. The outer contour of the smooth curve type inclined transition section includes an elliptical arc type, a polynomial curve type, or a spline curve type.

9. The nozzle according to claim 8, characterized in that, The inclined transition section is a smooth curve type. When the outer contour of the smooth curve type inclined transition section is an elliptical arc, the center of the end of the straight section is defined as the origin of the coordinate system, the downstream direction along the axial direction of the nozzle is defined as the z-axis, and the radial direction along the nozzle is defined as the r-axis. The curve equation of the inclined transition section satisfies: ； Where z and r are the coordinates of the equation of the control smooth curve, respectively; The axial length of the smooth, curved, inclined transition section; The outer diameter of the central fuel supply pipe.

10. The nozzle according to claim 8, characterized in that, The inclined transition section is an approximately straight inclined transition section, which includes a straight contraction section and an end arc transition section. The end arc transition section is tangentially connected to the straight contraction section, and the radius of the end arc transition section is... satisfy: Furthermore, the axial length of the approximately straight inclined transition section is greater than twice the outer diameter of the central fuel supply pipe.

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