A multi-nozzle micro-mix annular combustion chamber suitable for high hydrogen content fuel

Abstract

This invention provides a multi-nozzle micro-mixing annular combustor suitable for high-hydrogen-content fuels. It is enclosed by a casing, and the combustion zone is formed by a combustor head, an outer cylinder, and an inner cylinder. The combustor head is equipped with micro-mixing nozzles and head cooling holes, while the outer and inner cylinders are equipped with film cooling holes and mixing holes. Air enters the combustion zone through the micro-mixing nozzles, head cooling holes, film cooling holes, and mixing holes. Fuel is supplied through the main fuel channel and auxiliary fuel channel of the micro-mixing nozzles, thereby controlling the ratio of diffusion combustion and premixed combustion. By employing multiple micro-mixing nozzles and multiple micro-mixing units, this invention achieves a high degree of fuel and air stagement, allowing them to enter the combustion zone in a high-speed jet form for partial premixed combustion. Cooling gas and mixing gas are used to limit the size of the recirculation zone in the combustor, thereby reducing the residence time of combustion products.

Description

Technical Field

[0001] This application relates to the field of gas turbine combustor technology, specifically to a multi-nozzle micro-mixing annular combustor suitable for high hydrogen content fuels. Background Technology

[0002] With growing attention focused on the climate crisis and carbon emission reduction, carbon emissions from gas turbines in power generation and propulsion have come into focus. Hydrogen, as a highly efficient, clean, and zero-carbon emission fuel, is one of the best alternative fuels for achieving zero carbon emissions in gas turbines in the future. However, hydrogen has a high combustion temperature and rapid flame propagation speed, making it prone to backfire. Traditional gas turbine combustors cannot achieve ideal performance under high hydrogen content (volume fraction > 60%) hydrogen fuel conditions. Therefore, developing new hydrogen combustors and related technologies is crucial.

[0003] Micro-mixing combustors, as a promising type of hydrogen gas turbine combustor, have attracted the attention of major gas turbine developers such as GE and Kawasaki Heavy Industries, as well as many researchers. Compared to traditional dry, low-emission combustors, micro-mixing combustors employ multiple micro-mixing nozzles for fuel and oxidizer supply. Each micro-mixing nozzle contains multiple micro-mixing channel units, achieving a high degree of fuel and air staging, thereby achieving lower combustion temperatures and nitrogen oxide emissions. Although many micro-mixing nozzles have been developed, overcoming challenges such as localized high temperatures, backfire, and combustion stability during the combustion of high-hydrogen fuels remains a challenge. Currently, micro-mixing nozzles are rarely used in actual combustors, especially in annular combustors used in aero engines and small gas turbines. Summary of the Invention

[0004] In view of this, the present invention provides a multi-nozzle micro-mixing annular combustor suitable for combustion of fuels with high hydrogen content. Based on the annular combustor, the multi-nozzle micro-mixing annular combustor is improved by adopting a new micro-mixing nozzle design and optimized cooling vent arrangement, thereby enabling partial premixed combustion of pure hydrogen fuel under the high pressure and high temperature inlet conditions of typical gas turbines, and achieving low emissions and preventing backfire over a wide range of operating conditions.

[0005] This invention provides a multi-nozzle micro-mixing annular combustion chamber, comprising:

[0006] The casing is formed by the front wall, outer wall, and inner wall together creating the airflow area;

[0007] The combustion chamber, located inside the airflow region, is formed by a head cylinder, an outer cylinder, and an inner cylinder, and multiple air inlets are provided on the head cylinder, outer cylinder, and inner cylinder; and

[0008] A micro-mixing nozzle is disposed at the front of the head cylinder and extends forward to connect to the front wall. Multiple micro-mixing nozzles are evenly distributed circumferentially on the combustion chamber head cylinder, and each micro-mixing nozzle includes an array of multiple micro-mixing units. The micro-mixing unit is provided with a fuel passage and an air passage inside. The inlet end of the air passage is connected to the airflow area, and the outlet end of the air passage and the outlet end of the fuel passage converge and are connected to the combustion area.

[0009] Preferably, the outer cylinder has a rearwardly extending overlapping section at the outer rear part, through which the combustion-supporting gas enters the airflow area from the channel formed by the outer wall and the overlapping section; the outer cylinder has an inwardly extending outer cylinder contraction section at the inner rear part, and the inner cylinder has an inner cylinder contraction section at the rear, with the outer cylinder contraction section and the inner cylinder contraction section forming the outlet of the combustion area.

[0010] Preferably, the air inlet includes:

[0011] Head cooling holes; evenly distributed circumferentially in the head cylinder of the combustion chamber;

[0012] The outer cylinder has mixing holes; these holes are evenly arranged circumferentially outside the combustion chamber; and

[0013] Inner cylinder mixing holes; evenly distributed circumferentially within the combustion chamber cylinder;

[0014] The combustion gas in the airflow region enters the combustion chamber through the head cooling hole, the outer cylinder mixing hole, and the inner cylinder mixing hole.

[0015] Preferably, the multi-nozzle micro-mixing annular combustion chamber further includes:

[0016] Air film cooling holes are vertically formed on the outer cylinder and the inner cylinder, and are evenly distributed circumferentially; and

[0017] A baffle is disposed in the head cylinder of the combustion chamber, surrounds the outer periphery of each of the micro-mixing nozzles and extends rearward, and blocks the outlet direction of the gas film cooling hole.

[0018] Preferably, the array of multi-layer micro-mixing units included in the micro-mixing nozzle is arranged in a concentric circle, honeycomb, and / or polygonal pattern.

[0019] Preferably, the sidewall of the micro-mixing nozzle is provided with a plurality of air holes forming the inlet end of the air channel. The plurality of air holes are arranged in groups in the circumferential direction corresponding to the micro-mixing unit, and each group of air holes is evenly arranged in a matrix array.

[0020] Preferably, the fuel passage inside the micro-hybrid unit includes a main fuel passage, and the outlet of the main fuel passage is located axially behind the outlet front end of the micro-hybrid unit.

[0021] Preferably, the micro-mixing nozzle has a central auxiliary fuel channel inside, the axis of which coincides with the centerline of the micro-mixing nozzle, and an auxiliary fuel nozzle is provided inside the central auxiliary fuel channel to deliver fuel to the air channel in the form of a transverse jet.

[0022] Preferably, the micro-mixing nozzle has an edge auxiliary fuel channel inside, and the edge auxiliary fuel channel has multiple auxiliary fuel nozzles inside, so as to deliver fuel to the air channel in the form of a lateral jet.

[0023] Preferably, the number of the plurality of edge auxiliary fuel channels corresponds to the number of the micro-mixing units, and the plurality of edge auxiliary fuel channels are arranged in a concentric circle, honeycomb, or polygonal array on a plane perpendicular to the axis.

[0024] Preferably, the air channel outlet section is composed of two or more of the following: a contraction channel, a straight channel, and an expansion channel.

[0025] Preferably, a vortex generator is provided in the air channel.

[0026] Based on the above technical solutions, this invention expands the fuel applicability range of aero-engines by achieving micro-mixing combustion in an annular combustion chamber; by setting head cooling holes, film cooling holes, and mixing holes on the cylinder, the wall surface is effectively cooled and the size of the wall recirculation zone is reduced, significantly reducing the weight of the combustion chamber; by utilizing a higher airflow rate of the micro-mixing nozzle, a higher nozzle exit velocity is obtained, thereby effectively improving the anti-backfire performance of the micro-mixing nozzle; the micro-mixing nozzle of this invention uses a coaxial jet to mix with air in the main fuel channel, making the combustion state close to diffusion combustion, and uses a transverse jet to mix with air in the auxiliary fuel channel, making the combustion state close to premixed combustion, and by controlling the fuel ratio of these two, the diffusion combustion and premixed combustion ratio of the micro-mixing nozzle is adjusted, thereby achieving a balance between low flame temperature and anti-backfire performance; by adjusting the spacing of the micro-mixing nozzles, the spacing of the micro-mixing units, and the swirling direction of the vortex of adjacent micro-mixing units, this invention can obtain a uniform combustion chamber exit temperature distribution while preventing premature merging of the micro-mixing flame. Attached Figure Description

[0027] The accompanying drawings are used to provide a further understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application, but do not constitute a limitation on the technical solutions of this application.

[0028] Figure 1This is a cross-sectional view of the center section of a multi-nozzle micro-mixing annular combustion chamber suitable for high-hydrogen-content fuels provided by the present invention.

[0029] Figure 2 A cross-sectional view of the flow direction of the multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuels provided by the present invention;

[0030] Figure 3 Isometric view of the micro-mixing nozzle of the multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuels provided by the present invention;

[0031] Figure 4 Cross-sectional view of the micro-mixing nozzle outlet of a multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuels provided by the present invention.

[0032] Figure 5 A cross-sectional view of the center section of the micro-mixing nozzle of the multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuels provided by the present invention.

[0033] Figure 6 A cross-sectional view of the flow direction of the auxiliary fuel nozzle of the multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuels provided by the present invention.

[0034] Figure 7 A schematic diagram of the flow field at the central cross-section of a multi-nozzle micro-mixing annular combustion chamber suitable for high-hydrogen-content fuels provided by the present invention.

[0035] Figure label:

[0036] 1-Micro-mixing nozzle; 10-Micro-mixing unit; 11-Air hole; 12-Main fuel passage; 13-Air passage; 14-Swirl converter; 151-Central auxiliary fuel passage; 152-Edge auxiliary fuel passage; 16-Auxiliary fuel nozzle passage; 17-Contraction passage; 18-Straight passage; 19-Expansion passage;

[0037] 21-Anterior wall; 22-Outer wall; 23-Inner wall;

[0038] 3-Head cylinder;

[0039] 41-Outer cylinder; 42-Outer cylinder contraction section; 43-Overlap section

[0040] 51-Inner cylinder; 52-Inner cylinder contraction section

[0041] 6-Head cooling holes;

[0042] 71-Baffle; 72-Film cooling hole

[0043] 81-Outer cylinder mixing hole; 82-Inner cylinder mixing hole

[0044] A - Air import; B - Fuel import; B1 - Main fuel import; B2 - Secondary fuel import; C - Gas export. Detailed Implementation

[0045] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The descriptions of the exemplary embodiments are merely illustrative and are not intended to limit the invention or its application or use in any way. The invention can be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the invention clear and complete, and to fully express the scope of the invention to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps set forth in these embodiments should be interpreted as merely exemplary and not as limiting.

[0046] like Figures 1-2 As shown, in one aspect of the present invention, a multi-nozzle micro-mixing annular combustion chamber is provided, comprising a flow region formed by a front wall 21, an outer wall 22, and an inner wall 23, a combustion region formed by a head cylinder 3, an outer cylinder 41, and an inner cylinder 51, micro-mixing nozzles 1 uniformly arranged circumferentially on the head cylinder 3, and head cooling holes 6, film cooling holes 72, outer cylinder mixing holes 81, and inner cylinder mixing holes 82 uniformly arranged circumferentially on the combustion chamber cylinder; wherein, the outer wall 22 of the casing and the overlapping section 43 constitute an air inlet A; air is recirculated into the flow region enclosed by the casing; air enters the combustion region through the micro-mixing nozzles 1, head cooling holes 6, film cooling holes 72, outer cylinder mixing holes 81, and inner cylinder mixing holes 82.

[0047] like Figure 1 As shown, the film cooling baffle 71 extends rearward from the combustion chamber head 3 and is located below the film cooling hole 72. It is used to make the film cooling gas flow backward along the wall to achieve the effect of isolating the wall and the high temperature gas. The outer cylinder contraction section 42 and the inner cylinder contraction section 52 constitute the combustion chamber outlet C. The fuel enters through the fuel inlet B in front of the micro-mixing nozzle 1. The air and fuel are mixed in the micro-mixing nozzle for a short distance and then enter the combustion zone for partial premixed combustion.

[0048] Preferably, the air intake area of ​​the micro-mixing nozzle should account for more than 30% of the total air intake area of ​​the combustion chamber to obtain a higher micro-mixing nozzle exit velocity, thereby avoiding backfire; in a more preferred embodiment, such as Figure 1 As shown, the air intake area of ​​the micro-mixing nozzle 1 accounts for more than 50% of the total air intake area of ​​the combustion chamber, so as to ensure that the micro-mixing nozzle 1 has a high exit velocity, thereby improving the anti-backfire performance.

[0049] In a preferred example, such as Figure 1As shown, the edge of the combustion chamber head 3 adopts an inward inclined wall design to reduce the size of the wall recirculation zone in the combustion chamber; the head cooling hole 6 is perpendicular to the inclined wall of the combustion chamber head 3, so that the cooling gas is injected inward, which can limit the size of the micro-mixing flame at the outlet of the micro-mixing nozzle 1.

[0050] In a preferred example, such as Figure 1 As shown, the outer cylinder mixing holes 81 and the micro-mixing nozzle 1 are located on the same spanwise section, allowing the mixed gas to directly enter the high-temperature combustion gas, which can improve the mixing efficiency; the inner cylinder mixing holes 82 adopt two rows of staggered arrangement, which can improve the mixing efficiency of the mixed gas; in a preferred embodiment, as shown... Figure 2 As shown, 18 micro-mixing nozzles 1 were used, and a large spacing was maintained in the span direction, which can prevent the premature merging of the micro-mixing flame.

[0051] The present invention determines the combustion chamber flow field structure through the micro-mixing nozzle 1, head cooling hole 3, film cooling hole 72, outer cylinder mixing hole 81, and inner cylinder mixing hole 82. Therefore, the present invention can configure the area and number of each inlet hole according to the inlet conditions, so as to reduce the size of the recirculation zone in the combustion chamber flow field while achieving stable combustion and effective cooling in the combustion chamber, thereby shortening the residence time of high-temperature combustion products and reducing nitrogen oxide emissions. Preferably, the number of head cooling hole, film cooling hole, outer cylinder mixing hole, and inner cylinder mixing hole should be an integer multiple of the number of micro-mixing nozzles to improve the symmetry of the combustion chamber flow field and reduce the combustion chamber outlet temperature distribution coefficient.

[0052] like Figures 3-6 As shown, the micro-mixing nozzle 1 of the present invention includes a multi-layer array of micro-mixing units 10, air holes 11, a main fuel channel 12, an air channel 13, a swirler 14, a central auxiliary fuel channel 151, and an edge auxiliary fuel channel 152. The auxiliary fuel channel also includes several auxiliary fuel nozzle channels 16. The outlet section of the micro-mixing unit 10 is composed of two or more of the following: a contraction channel 17, a straight channel 18, and an expansion channel 19. The air holes 11 are located on the outer wall of the micro-mixing nozzle 1 and correspond one-to-one with the micro-mixing units 10, allowing sufficient air to enter the air channel 12.

[0053] like Figure 5As shown, the main fuel channel 12 is located in the air channel 13, and its outlet is located before or flush with the outlet of the micro-mixing unit 10, so that the main fuel B1 and air are mixed in the form of a coaxial jet. The mixing effect is poor under high pressure and high speed flow conditions, thus approaching the diffusion combustion mode. The central auxiliary fuel channel 151 is coaxial with the micro-mixing nozzle 1, and the edge auxiliary fuel channel 152 is located between adjacent micro-mixing units 10. The auxiliary fuel nozzle channel 16 inside the auxiliary fuel channel delivers the auxiliary fuel B2 into the air channel 12 in the form of a transverse jet. The mixing intensity is high, thus approaching the premixed combustion mode. The main fuel B1 of the present invention is closer to the diffusion combustion mode and has good anti-backfire performance, but due to poor mixing, the flame temperature will be higher. The auxiliary fuel B2 is closer to the premixed combustion mode, with good mixing performance and thus a lower flame temperature, but it is more prone to backfire. The backfire of the micro-mixing nozzle is also related to the fuel type and inlet conditions. Therefore, the technical solution provided by the present invention can take into account the actual operating conditions by controlling the ratio of the main fuel B1 and the auxiliary fuel B2 and their related channel dimensions.

[0054] like Figure 5 As shown, the swirler 14 is located in the air passage 13, which can enhance the mixing performance of fuel and air. In addition, the swirlers 14 of multiple micro-mixing units 10 constitute a micro-swirling array. In this way, the present invention can flexibly adjust the main flow field characteristics of the combustion chamber, making the combustion process more controlled, thereby effectively reducing the flame residence time and controlling the flame temperature.

[0055] In a preferred example, such as Figure 3 and Figure 4 As shown, the micro-mixing nozzle 1 employs a single layer of quadrilateral micro-mixing unit array, achieving micro-mixing combustion while ensuring a large micro-mixing unit size to facilitate processing; in a preferred embodiment, as... Figure 3 As shown, the air vents are arranged in a 3×3 rectangular array, which allows a large amount of air to enter the air channel 12.

[0056] In a preferred example, such as Figure 4 As shown, the cyclone separator 14 uses four curved blades, which achieves the swirling effect in a small channel while reducing the processing complexity and friction loss by having fewer blades. The cyclone separators 14 of adjacent micro-mixing units 10 adopt the same swirling direction, which can improve the overall swirling intensity of the combustion chamber flow field, thereby improving the temperature uniformity of the combustion chamber outlet.

[0057] In a preferred example, such as Figure 5 As shown, the inner diameter of the main fuel passage 12 is relatively smaller than that of the air passage 12, and the outlet velocity of the main fuel flow B1 is higher, resulting in a higher ejection ratio. This increases the inlet flow rate of the air orifice 11, increases the outlet velocity of the micro-mixing unit 10, and thus improves the anti-backfire performance. Figure 6As shown, the auxiliary fuel nozzle channel 16 has a smaller diameter, which can increase the penetration depth of the auxiliary fuel flow B2, thereby enabling the fuel to obtain a larger distribution range in the air channel 12, i.e., improving the mixing performance; each micro-mixing unit 10 has 3 auxiliary fuel nozzle channels 16 to supply auxiliary fuel B2 in the form of a transverse jet, thereby obtaining better mixing performance.

[0058] This invention achieves high-level separation of fuel B and air A through an array of multiple micro-mixing nozzles 1 and micro-mixing units 10, which is beneficial for reducing flame temperature and shortening flame size; for example Figure 7 As shown, after the micro-mixing nozzle 1 determines the main characteristics of the combustion chamber flow field (i.e., the small recirculation zone at the nozzle outlet and the elimination of the central recirculation zone in the combustion chamber), the present invention controls the flow field by adjusting the area and direction of the head cooling hole 6, the gas film cooling hole 72, the outer cylinder mixing hole 81 and the inner cylinder mixing hole 82. This reduces the size of unnecessary angular recirculation zone and wall recirculation zone to reduce the residence time of combustion products, thereby reducing nitrogen oxide emissions.

[0059] In summary, the multi-nozzle micro-mixing annular combustion chamber of this invention achieves a high degree of fuel and air separation through multiple uniformly arranged micro-mixing nozzles, effectively reducing flame size and temperature. The high proportion of the micro-mixing nozzle inlet area results in a high nozzle exit velocity, thus effectively preventing backfire. The inclusion of corresponding head cooling holes, film cooling holes, and mixing holes on the combustion chamber shell reduces the size of the recirculation zone while cooling the wall surface. A main fuel channel enables diffusion combustion, while a secondary fuel channel enables premixed combustion. Controlling the proportion of these two fuels according to actual conditions allows for adjustment of the premixed combustion and diffusion combustion ratio of the micro-mixing nozzles, achieving a balance between low flame temperature and high backfire resistance. Furthermore, controlling the distance between micro-mixing nozzles, the distance between micro-mixing units, and the swirl direction of adjacent cyclones ensures uniform combustion chamber outlet temperature distribution while preventing premature merging of the micro-mixed flame.

[0060] The multi-nozzle micro-mixing annular combustion chamber provided by this invention is externally enclosed by a casing. The internal annular combustion chamber consists of a head cylinder, an outer cylinder, and an inner cylinder. Multiple micro-mixing nozzles are uniformly arranged circumferentially at the head of the annular combustion chamber. Each micro-mixing nozzle is composed of an array of multiple micro-mixing units, thereby achieving a high degree of fuel and air separation, which is beneficial for reducing flame size and pollution emissions. Air flows back into the chamber through the inlet channel formed by the casing and the outer cylinder, and then enters the air channel of the micro-mixing unit through air holes on the micro-mixing nozzles. Fuel enters the micro-mixing nozzles through the main fuel channel and the auxiliary fuel channel. The main fuel channel mixes with air in a coaxial jet form, resulting in a low mixing intensity, closer to diffusion combustion. The auxiliary fuel channel mixes with air in a transverse jet form, resulting in a high mixing intensity, closer to premixed combustion. By controlling the fuel ratio of these two types, the premixing / diffusion combustion degree of the micro-mixing nozzle can be changed, thereby achieving a balance between reducing flame temperature and ensuring anti-backfire performance. In addition, each cylinder of the combustion chamber is equipped with head cooling holes, film cooling holes and mixing holes. While cooling the wall surface, the size of the combustion chamber recirculation zone can also be reduced to reduce the residence time of combustion products, thereby further reducing nitrogen oxide emissions.

[0061] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A multi-injector micro-mix annular combustion chamber suitable for high hydrogen content fuels, characterized in that, include: The casing is formed by the front wall (21), outer wall (22) and inner wall (23) together to form the airflow area; The combustion chamber is located inside the airflow area and is formed by the head cylinder (3), the outer cylinder (41) and the inner cylinder (51). Multiple air inlets are provided on the head cylinder (3), the outer cylinder (41) and the inner cylinder (51). as well as A micro-mixing nozzle (1) is disposed at the front of the head cylinder (3) and extends forward to connect to the front wall (21). Multiple micro-mixing nozzles are evenly distributed circumferentially on the head cylinder (3) of the combustion chamber, and each micro-mixing nozzle contains an array of multiple micro-mixing units (10). The micro-mixing unit (10) is provided with a fuel passage and an air passage (13) inside. The inlet end of the air passage (13) is connected to the airflow area. The outlet end of the air passage (13) and the outlet end of the fuel passage converge and are connected to the combustion area. The fuel passage inside the micro-mixing unit (10) includes a main fuel passage (12), the outlet of the main fuel passage (12) is located axially behind the outlet front end of the micro-mixing unit (10); the micro-mixing nozzle (1) is provided with a central auxiliary fuel passage (151), the axis of the central auxiliary fuel passage (151) coincides with the center line of the micro-mixing nozzle (1), and the central auxiliary fuel passage (151) is provided with an auxiliary fuel nozzle (16) to deliver fuel to the air passage (13) in the form of a transverse jet.

2. The multi-nozzle micro-mixing annular combustion chamber of claim 1, wherein, The outer cylinder (41) has a rearwardly extending overlapping section (43) at the outer rear part, and the combustion-supporting gas enters the airflow area from the channel formed by the outer wall (22) and the overlapping section (43); the outer cylinder (41) has an inwardly extending outer cylinder contraction section (42) at the inner rear part, and the inner cylinder (51) has an inner cylinder contraction section (52) at the rear part, and the outer cylinder contraction section (42) and the inner cylinder contraction section (52) constitute the outlet of the combustion area.

3. The multi-nozzle micro-mixing annular combustion facility according to claim 1, characterized in that, The air inlet includes: Head cooling holes (6); evenly arranged circumferentially on the head cylinder of the combustion chamber (3). The outer cylinder mixing holes (81); are evenly arranged circumferentially on the outer cylinder (41) of the combustion chamber; and Inner cylinder mixing holes (82); uniformly arranged circumferentially in the combustion chamber cylinder (51). The combustion gas in the airflow region enters the combustion chamber through the head cooling hole (6), the outer cylinder mixing hole (81), and the inner cylinder mixing hole (82).

4. The multi-nozzle micro-mixing annular combustion facility according to claim 3, characterized in that, Also includes: Air film cooling holes (72) are vertically opened on the outer cylinder (41) and the inner cylinder (51) and are evenly distributed along the circumference; as well as A baffle (71) is provided on the head cylinder (3) of the combustion chamber, surrounds the outer periphery of each of the micro-mixing nozzles (1) and extends rearward, and blocks the outlet direction of the gas film cooling hole (72).

5. The multi-nozzle micro-mixing annular combustion facility according to claim 1, characterized in that, The array of multi-layer micro-mixing units (10) included in the micro-mixing nozzle (1) can be concentric, honeycomb and / or polygonal.

6. The multi-nozzle micro-mixing annular combustion facility according to claim 5, characterized in that, The sidewall of the micro-mixing nozzle (1) is provided with a plurality of air holes (11) that form the inlet end of the air channel (13). The plurality of air holes (11) are arranged in groups in the circumferential direction corresponding to the micro-mixing unit (10), and each group of air holes (11) is evenly arranged in a matrix array.

7. The multi-nozzle micro-mixing annular combustion facility of claim 1, wherein, The micro-mixing nozzle (1) is provided with an edge auxiliary fuel channel (152) inside, and the edge auxiliary fuel channel (152) is provided with multiple auxiliary fuel nozzles (16) inside, so as to deliver fuel to the air channel (13) in the form of a transverse jet.

8. The multi-nozzle micro-mixing annular combustion facility according to claim 7, characterized in that, The number of the plurality of edge auxiliary fuel channels (152) corresponds to the number of the micro-mixing units (10), and the plurality of edge auxiliary fuel channels (152) are arranged in a concentric circle, honeycomb or polygonal array on a plane perpendicular to the axis.

9. The multi-nozzle micro-mixing annular combustion facility of claim 1, wherein, The outlet section of the air passage (13) is composed of two or more of the following: a contraction passage (17), a straight passage (18), and an expansion passage (19).

10. The multi-nozzle micro-mixing annular combustion facility of claim 1, wherein, A vortex generator (14) is provided in the air passage (13).

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