Multi-nozzle micro-mixing annular combustion chamber suitable for high-hydrogen-content fuel

Abstract

The invention provides a multi-nozzle micro-mixing annular combustion chamber suitable for high-hydrogen-content fuel. The multi-nozzle micro-mixing annular combustion chamber is wrapped by a cartridge receiver, and a combustion area is defined by a combustion chamber head, an outer barrel and an inner barrel. A micro-mixing nozzle and a head cooling hole are arranged at the head of the combustion chamber; and an air film cooling hole and a mixing hole are formed in the outer barrel and the inner barrel of the combustion chamber. Air enters a combustion area through the micro-mixing nozzle, the head cooling hole, the air film cooling hole and the mixing hole, fuel is jointly supplied through a main fuel channel and an auxiliary fuel channel of the micro-mixing nozzle, and therefore the proportion of diffusion combustion and premixed combustion can be controlled. By the adoption of the multiple micro-mixing nozzles and the multiple micro-mixing units, fuel and air are highly graded and enter a combustion area in a high-speed jet flow mode to be partially premixed and combusted, the size of a backflow area in the combustion chamber is limited through cooling gas and mixed gas, and therefore the retention time of combustion products is shortened.

Description

Technical Field

[0001] The present application relates to the technical field of gas turbine combustion chambers, and in particular to a multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuels. Background Art

[0002] As people pay more attention to the climate crisis and carbon emission reduction, carbon emissions from gas turbines in the power generation and propulsion fields have gradually come into people's view. Hydrogen, as an efficient, clean, zero-carbon emission fuel, is one of the best alternative fuels for gas turbines to achieve zero carbon emissions in the future. However, hydrogen has a high combustion temperature and a fast flame propagation speed, and is prone to flashback. Traditional gas turbine combustors cannot achieve ideal performance under high hydrogen content (volume fraction>60%) hydrogen fuel conditions, so it is very important to develop new hydrogen combustors and related technologies.

[0003] As a very promising hydrogen gas turbine combustor, the micro-mixing combustor has attracted the attention of major gas turbine developers such as General Electric and Kawasaki Heavy Industries and many researchers. Compared with the traditional dry low-emission combustor, the micro-mixing combustor uses multiple micro-mixing nozzles to supply fuel and oxidant. Each micro-mixing nozzle contains multiple micro-mixing channel units, which largely achieves a high degree of fuel and air grading, thereby achieving lower combustion temperature and nitrogen oxide emissions. Although many micro-mixing nozzles have been developed, it is still a challenge to simultaneously overcome the problems of local high temperature, flashback and combustion stability during the combustion of high hydrogen content fuels. At present, micro-mixing nozzles are rarely used in actual combustors, especially in annular combustors used in aircraft engines and small gas turbines. Summary of the invention

[0004] In view of this, the present invention provides a multi-nozzle micro-mixing annular combustion chamber suitable for the combustion of high-hydrogen content fuel. The multi-nozzle micro-mixing annular combustion chamber is improved on the basis of the annular combustion chamber, and specifically adopts a new micro-mixing nozzle design and an optimized cooling air hole arrangement, so that partial premixed combustion of pure hydrogen fuel can be achieved under the high-pressure and high-temperature inlet conditions of a typical gas turbine, and low emissions and flashback prevention can be achieved within a wide range of operating conditions.

[0005] The present invention provides a multi-nozzle micro-mixing annular combustion chamber, which comprises:

[0006] The casing is composed of a front wall, an outer wall and an inner wall, which together form an airflow area;

[0007] A combustion chamber is located inside the airflow area, and is enclosed by a head cylinder, an outer cylinder and an inner cylinder to form a combustion area, and a plurality of air inlet holes are opened on the head cylinder, the outer cylinder and the inner cylinder; and

[0008] A micro-mixing nozzle is arranged at the front part of the head cylinder and extends forward to be connected to the front wall. A plurality of micro-mixing nozzles are evenly distributed on the head cylinder of the combustion chamber along the circumferential direction, and each of the micro-mixing nozzles includes an array of multi-layer micro-mixing units. A fuel channel and an air channel are arranged inside the micro-mixing unit. The inlet end of the air channel is connected to the airflow flow area, and the outlet end of the air channel and the outlet end of the fuel channel converge and are connected to the combustion area.

[0009] Preferably, an overlapping section extending backward is provided at the outer rear portion of the outer cylinder, and the combustion-supporting gas enters the airflow flow area from the channel formed by the outer wall and the overlapping section; an outer cylinder contraction section extending inward is provided at the inner rear portion of the outer cylinder, and an inner cylinder contraction section is provided at the rear of the inner cylinder, and the outer cylinder contraction section and the inner cylinder contraction section constitute the outlet of the combustion area.

[0010] Preferably, the air inlet comprises:

[0011] Head cooling holes; evenly arranged in the circumferential direction on the head cylinder of the combustion chamber;

[0012] The outer cylinder mixing holes are evenly arranged in the circumferential direction outside the combustion chamber; and

[0013] The mixing holes in the inner cylinder are evenly arranged in the cylinder of the combustion chamber along the circumferential direction;

[0014] The combustion-supporting gas in the airflow flow area 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 comprises:

[0016] Air film cooling holes are vertically opened on the outer cylinder and the inner cylinder and evenly distributed along the circumferential direction; and

[0017] The baffle is arranged on the combustion chamber head cylinder, surrounds the outer periphery of each of the micro-mixing nozzles and extends backwards, and blocks the gas outlet direction of the air film cooling hole.

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

[0019] Preferably, the side wall of the micro-mixing nozzle is provided with a plurality of air holes constituting 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 units, and the air holes in each group are evenly arranged in a matrix array.

[0020] Preferably, the fuel channel inside the micro-mixing unit comprises a main fuel channel, and an outlet of the main fuel channel is axially located behind a front end of an outlet of the micro-mixing unit.

[0021] Preferably, a central secondary fuel channel is provided inside the micro-mixing nozzle, the axis of the central secondary fuel channel coincides with the center line of the micro-mixing nozzle, and a secondary fuel nozzle is provided in the central secondary fuel channel to deliver fuel to the air channel in the form of a lateral jet.

[0022] Preferably, an edge secondary fuel channel is provided inside the micro-mixing nozzle, and a plurality of secondary fuel nozzles are provided inside the edge secondary fuel channel to deliver the fuel to the air channel in the form of a lateral jet.

[0023] Preferably, the number of the plurality of edge subsidiary fuel channels corresponds to the number of the micro-mixing units, and the plurality of edge subsidiary fuel channels are 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 a contraction channel, a straight channel and an expansion channel.

[0025] Preferably, a cyclone is provided in the air passage.

[0026] Based on the above technical scheme, the present invention realizes micro-mixing combustion in an annular combustion chamber, thereby expanding the fuel application range of aircraft engines; by arranging head cooling holes, air 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, thereby greatly reducing the weight of the combustion chamber; a higher nozzle outlet velocity is obtained by utilizing a higher micro-mixing nozzle air flow rate, thereby effectively improving the anti-flashback performance of the micro-mixing nozzle; the micro-mixing nozzle of the present invention adopts coaxial jet mixing with air in the main fuel channel to make the combustion state close to diffusion combustion, and adopts transverse jet mixing with air in the auxiliary fuel channel to make the combustion state close to premixed combustion, and adjusts the diffusion combustion and premixed combustion ratio of the micro-mixing nozzle by controlling the fuel ratio of the two, thereby achieving a balance between low flame temperature and anti-flashback performance; the present invention can obtain a uniform combustion chamber outlet temperature distribution while preventing the micro-mixing flame from merging prematurely by adjusting the spacing of the micro-mixing nozzles, the spacing of the micro-mixing units and the rotation direction of the swirlers of adjacent micro-mixing units. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are used to provide a further understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application, but do not constitute a limitation on the technical solution of the present application.

[0028] Figure 1A central cross-sectional view of a multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuel provided by the present invention;

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

[0030] Figure 3 An isometric diagram of a micro-mixing nozzle of a multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuel provided by the present invention;

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

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

[0033] Figure 6 A cross-sectional view of a flow section of a secondary fuel nozzle of a micro-mixing nozzle of a multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuel provided by the present invention;

[0034] Figure 7 Schematic diagram of the flow field of the central cross section of the multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuel provided by the present invention

[0035] Reference numerals:

[0036] 1-micro-mixing nozzle; 10-micro-mixing unit; 11-air hole; 12-main fuel channel; 13-air channel; 14-swirler; 151-central auxiliary fuel channel; 152-edge auxiliary fuel channel; 16-auxiliary fuel nozzle channel; 17-contraction channel; 18-straight channel; 19-expansion channel;

[0037] 21-front wall; 22-outer wall; 23 inner wall;

[0038] 3-head cylinder;

[0039] 41-outer cylinder; 42-contraction section of outer cylinder; 43-lap section

[0040] 51-inner cylinder; 52-contraction section of inner cylinder

[0041] 6-Head cooling holes;

[0042] 71- baffle; 72- air film cooling hole

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

[0044] A-air inlet; B-fuel inlet; B1-main fuel inlet; B2-auxiliary fuel inlet; C-gas outlet. DETAILED DESCRIPTION

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

[0046] like Figures 1-2 As shown, in one aspect of the present invention, a multi-nozzle micro-mixing annular combustion chamber is provided, which includes a flow area composed of a front wall 21, an outer wall 22 and an inner wall 23, a combustion area composed of a head cylinder 3, an outer cylinder 41 and an inner cylinder 51, a micro-mixing nozzle 1 uniformly arranged on the head cylinder 3 along the circumferential direction, a head cooling hole 6, an air film cooling hole 72, an outer cylinder mixing hole 81 and an inner cylinder mixing hole 82 uniformly arranged on the combustion chamber cylinder along the circumferential direction; wherein, the outer wall 22 of the casing and the overlap section 43 constitute an air inlet A; air enters the flow area wrapped by the casing by backflow; air enters the combustion area through the micro-mixing nozzle 1, the head cooling hole 6, the air film cooling hole 72, the outer cylinder mixing hole 81 and the inner cylinder mixing hole 82.

[0047] like Figure 1 As shown, the film cooling baffle 71 is formed by extending backward from the combustion chamber head 3 and is located below the film cooling hole 72, and is used to make the film cooling gas flow backward along the wall surface to achieve the effect of isolating the wall surface 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, and the air and fuel are mixed in a short distance inside the micro-mixing nozzle and then enter the combustion area for partial premixed combustion.

[0048] Preferably, the air intake area of ​​the micro-mixing nozzle should account for more than 30% of the total intake area of ​​the combustion chamber to obtain a higher micro-mixing nozzle outlet velocity, thereby avoiding flashback. In a more preferred embodiment, 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 higher outlet velocity, thereby improving the anti-flashback performance.

[0049] In a preferred embodiment, Figure 1As shown, the edge of the combustion chamber head 3 adopts an inwardly inclined wall design to reduce the size of the wall recirculation area 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 sprayed inward, which can limit the size of the micro-mixing flame at the outlet of the micro-mixing nozzle 1.

[0050] In a preferred embodiment, Figure 1 As shown, the outer cylinder mixing hole 81 and the micro-mixing nozzle 1 are located in the same spanwise section, so that the mixed gas directly enters the high-temperature combustion gas, which can improve the mixing efficiency; the inner cylinder mixing hole 82 adopts two rows of staggered arrangement, which can improve the mixing efficiency of the mixed gas; in a preferred example, as Figure 2 As shown, 18 micro-mixing nozzles 1 are used and a large spacing is maintained in the span direction, which can avoid the early merging of the micro-mixing flames.

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

[0052] like Figures 3 to 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 a plurality of auxiliary fuel nozzle channels 16. The outlet section of the micro-mixing unit 10 is composed of two or more of a contraction channel 17, a straight channel 18, and an expansion channel 19; wherein the air holes 11 are located on the outer wall of the micro-mixing nozzle 1, corresponding one-to-one with the micro-mixing units 10, so that sufficient air enters 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 is mixed with the air in the form of a coaxial jet. The mixing effect under high pressure and high speed flow conditions is poor, so it is close to 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 lateral jet, and the mixing intensity is high, so it is close to the premixed combustion mode. The main fuel B1 of the present invention is closer to the diffusion combustion mode and has good anti-flashback performance, but due to poor mixing, a higher flame temperature will appear. The auxiliary fuel B2 is closer to the premixed combustion mode, has good mixing performance and thus has a lower flame temperature, but is more prone to flashback. The flashback of the micro-mixing nozzle is also related to the fuel type and the inlet working condition. Therefore, the technical solution provided by the present invention can take into account the actual working condition needs by controlling the ratio of the main fuel B1 and the auxiliary fuel B2 and the relevant channel size.

[0054] like Figure 5 As shown, the swirler 14 is located in the air channel 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-swirl array, whereby the present invention can flexibly adjust the main flow field characteristics of the combustion chamber to make the combustion process more controlled, thereby effectively reducing the flame residence time and controlling the flame temperature.

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

[0056] In a preferred embodiment, Figure 4 As shown, the swirler 14 adopts 4 curved blades. While achieving the swirl effect of a small-size channel, the smaller number of blades reduces the processing complexity and friction loss; the swirlers 14 of adjacent micro-mixing units 10 adopt the same rotation direction, which can improve the overall swirl intensity of the combustion chamber flow field, thereby improving the temperature uniformity of the combustion chamber outlet.

[0057] In a preferred embodiment, Figure 5 As shown, the inner diameter of the main fuel channel 12 is smaller than that of the air channel 12, and the outlet velocity of the main fuel flow B1 is higher, so that it has a higher injection ratio, which can increase the inlet flow rate of the air hole 11 and the outlet velocity of the micro-mixing unit 10, thereby improving the anti-flashback performance; Figure 6As shown, the secondary fuel nozzle channel 16 adopts a smaller diameter, which can increase the penetration depth of the secondary fuel flow B2, so that the fuel can obtain a larger distribution range in the air channel 12, that is, improve the mixing performance; each micro-mixing unit 10 has 3 secondary fuel nozzle channels 16 to supply the secondary fuel B2 in the form of lateral jets, so as to obtain better mixing performance.

[0058] The present invention realizes a high degree of grading of fuel B and air A through a plurality of micro-mixing nozzles 1 and an array of micro-mixing units 10, which is beneficial to reducing the flame temperature and shortening the flame size; 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 of the combustion chamber), the present invention controls the flow field by adjusting the area and direction of the head cooling hole 6, the film cooling hole 72, the outer cylinder mixing hole 81 and the inner cylinder mixing hole 82, thereby reducing the unnecessary corner recirculation zone and the wall recirculation zone size to reduce the residence time of the combustion products, thereby reducing nitrogen oxide emissions.

[0059] In summary, the multi-nozzle micro-mixing annular combustion chamber of the present invention achieves a high degree of fuel and air grading through multiple evenly arranged micro-mixing nozzles, effectively reduces the flame size and temperature, and adopts a higher proportion of micro-mixing nozzle intake area to obtain a higher nozzle outlet velocity, thereby effectively preventing flashback. The corresponding head cooling holes, air film cooling holes and mixing holes are arranged on the combustion chamber cylinder, which can reduce the size of the recirculation zone while cooling the wall surface. The main fuel channel is arranged to achieve diffusion combustion, and the auxiliary fuel channel is arranged to achieve premixed combustion. The proportion of these two fuels can be controlled according to actual conditions, that is, the ratio of premixed combustion and diffusion combustion of the micro-mixing nozzle can be adjusted, thereby achieving a balance between low flame temperature and high anti-flashback performance. In addition, by controlling the distance between the micro-mixing nozzles, the distance between the micro-mixing units and the rotation direction of adjacent swirlers, the premature merging of the micro-mixing flame can be prevented while ensuring uniform distribution of the combustion chamber outlet temperature.

[0060] The outer part of the multi-nozzle micro-mixing annular combustion chamber provided by the present invention is formed by wrapping the casing, and the inner annular combustion chamber is composed of a head cylinder, an outer cylinder and an inner cylinder. A plurality of micro-mixing nozzles are evenly arranged along the circumference at the head of the annular combustion chamber, and each micro-mixing nozzle is composed of a plurality of micro-mixing unit arrays, thereby achieving a high degree of grading of fuel and air, which is beneficial to reducing the flame size and pollution emissions. After the air flows back through the inlet channel formed by the casing and the outer cylinder, it enters the air channel of the micro-mixing unit through the air hole on the micro-mixing nozzle, and the fuel can enter the micro-mixing nozzle through the main fuel channel and the auxiliary fuel channel, wherein the main fuel channel is mixed with the air in the form of a coaxial jet, and the mixing intensity is low, which is closer to diffusion combustion, while the auxiliary fuel channel is mixed with the air in the form of a transverse jet, and the mixing intensity is high, which is closer to premixed combustion. By controlling the fuel ratio of the two, the premixing / diffusion combustion degree of the micro-mixing nozzle can be changed, thereby achieving a balance between reducing the flame temperature and ensuring the anti-flashback performance. In addition, head cooling holes, film cooling holes and mixing holes are provided on each cylinder of the combustion chamber. While cooling the wall surface, the size of the recirculation zone of the combustion chamber can also be reduced to reduce the residence time of the combustion products, thereby further reducing nitrogen oxide emissions.

[0061] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A multi-nozzle micro-mixing annular combustion chamber suitable for high hydrogen content fuel, characterized in that: include: The casing is enclosed by a front wall (21), an outer wall (22) and an inner wall (23) to form an airflow area; A combustion chamber is located inside the airflow area, and is enclosed by the head cylinder (3), the outer cylinder (41) and the inner cylinder (51) to form a combustion area, and a plurality of air inlet holes 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 arranged at the front of the head barrel (3) and extends forward to be connected to the front wall (21). A plurality of micro-mixing nozzles are evenly distributed on the combustion chamber head barrel (3) along the circumferential direction, and each micro-mixing nozzle comprises an array of multi-layer micro-mixing units (10). A fuel channel and an air channel (13) are provided inside the micro-mixing unit (10). The inlet end of the air channel (13) is connected to the airflow flow area, and the outlet end of the air channel (13) and the outlet end of the fuel channel converge and are connected to the combustion area.

2. The multi-nozzle micro-mixing annular combustion chamber according to claim 1, characterized in that: The outer rear portion of the outer cylinder (41) is provided with an overlapping section (43) extending backward, 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) is provided with an outer cylinder contraction section (42) extending inward, and the inner cylinder (51) is provided with an inner cylinder contraction section (52) at the rear portion; the outer cylinder contraction section (42) and the inner cylinder contraction section (52) form the outlet of the combustion area.

3. The multi-nozzle micro-mixing annular combustion chamber according to claim 1, characterized in that: The air inlet comprises: Head cooling holes (6) are evenly arranged in the circumferential direction on the combustion chamber head cylinder (3); The outer cylinder mixing holes (81) are evenly arranged in the circumferential direction on the outer cylinder (41) of the combustion chamber; and The inner cylinder mixing holes (82) are evenly arranged in the combustion chamber cylinder (51) along the circumferential direction; The combustion-supporting gas in the airflow flow area 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 chamber 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 circumferential direction; as well as A baffle (71) is arranged on the combustion chamber head barrel (3), surrounds the outer circumference of each of the micro-mixing nozzles (1) and extends backwards, and blocks the gas outlet direction of the air film cooling hole (72).

5. The multi-nozzle micro-mixing annular combustion chamber according to claim 1, characterized in that: The array form of the multi-layer micro-mixing units (10) included in the micro-mixing nozzle (1) includes a concentric circle form, a honeycomb form and / or a polygonal form.

6. The multi-nozzle micro-mixing annular combustion chamber according to claim 5, characterized in that: The side wall of the micro-mixing nozzle (1) is provided with a plurality of air holes (11) constituting the inlet end of the air channel (13); the plurality of air holes (11) are arranged in groups in a 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 chamber according to claim 1, characterized in that: The fuel channel inside the micro-mixing unit (10) comprises a main fuel channel (12), and the outlet of the main fuel channel (12) is axially located behind the front end of the outlet of the micro-mixing unit (10).

8. The multi-nozzle micro-mixing annular combustion chamber according to claim 7, characterized in that: A central secondary fuel channel (151) is provided inside the micro-mixing nozzle (1), the axis of the central secondary fuel channel (151) coincides with the center line of the micro-mixing nozzle (1), and a secondary fuel nozzle (16) is provided inside the central secondary fuel channel (151) to deliver fuel to the air channel (13) in the form of a lateral jet.

9. The multi-nozzle micro-mixing annular combustion chamber according to claim 8, characterized in that: The micro-mixing nozzle (1) is provided with an edge secondary fuel channel (152) inside, and a plurality of secondary fuel nozzles (16) are provided inside the edge secondary fuel channel (152) so as to deliver fuel to the air channel (13) in the form of a transverse jet.

10. The multi-nozzle micro-mixing annular combustion chamber according to claim 9, 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.

11. The multi-nozzle micro-mixing annular combustion chamber according to claim 7, characterized in that: The outlet section of the air channel (13) is composed of two or more of a contraction channel (17), a straight channel (18) and an expansion channel (19).

12. The multi-nozzle micro-mixing annular combustion chamber according to claim 1, characterized in that: A cyclone (14) is provided in the air passage (13).

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