Combustion chamber and gas turbine

Abstract

The present invention discloses a combustion chamber and a gas turbine, wherein the combustion chamber comprises: a combustion chamber head; a flame tube, wherein the flame tube is integrally connected to the combustion chamber head, and an igniter is arranged inside the flame tube; a blunt body, wherein the blunt body is arranged inside the flame tube; a fuel premixing structure, wherein the fuel premixing structure is arranged at the combustion chamber head and the outlet is connected to the flame tube, and the fuel premixing structure is suitable for premixing the fuel to be burned; and a cooling medium injection structure, wherein the cooling medium injection structure is arranged inside the blunt body. The present invention adopts a method of combining high-speed injection of premixed fuel gas with a blunt body, which can make the premixed gas of hydrogen and air burn stably within a reasonable design area to prevent backfire; and by injecting a cooling medium into the flame tube, the generation of thermal nitrogen oxides is significantly reduced, and pollutant emissions are reduced; and secondary hydrogen is injected behind the blunt body, which effectively improves the flow field structure in the flame tube and the temperature distribution at the combustion chamber outlet.

Description

Technical Field

[0001] The present invention relates to the technical field of gas turbines, and in particular to a combustion chamber and a gas turbine. Background Art

[0002] At present, gas turbines have been widely used in various industries such as energy, electricity, and ships. The combustion chamber is one of the essential components of a gas turbine. The chemical energy contained in the fuel in the combustion chamber is converted into heat energy through the combustion chemical reaction, forming high-temperature (usually high-pressure) combustion products to drive the turbine to do work. Usually, gas turbines use natural gas as fuel, which releases a large amount of carbon dioxide when burned, significantly increasing carbon emissions. Therefore, finding a clean fuel to replace traditional hydrocarbon fuels is the only way forward in the future.

[0003] As a clean and efficient energy source, hydrogen is of great significance in energy technology reform and energy development strategy. In recent years, it has developed rapidly due to its advantages such as cleanliness, environmental protection and sustainable utilization. It has been widely used in transportation, chemical industry and other fields. When hydrogen burns, the only combustion product is water. If hydrogen is used as gas turbine fuel, carbon emissions can be significantly reduced. Because hydrogen burns quickly during premixed combustion, it faces the risk of flashback. So far, there is no combustion chamber that can completely use hydrogen as fuel. At present, most combustion chambers use non-premixed diffusion combustion, which will cause the local temperature in the combustion zone to be too high, resulting in increased nitrogen oxide emissions, aggravated pollution to the environment, and poor uniformity of the combustion chamber outlet temperature distribution.

[0004] Therefore, it is necessary to rationally develop and improve the overall structure of the combustion chamber to reduce carbon emissions. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the problem of increased nitrogen oxide emissions caused by the current non-premixed diffusion combustion method used in the combustion chamber, thereby providing a combustion chamber and a gas turbine.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] Combustion chamber, comprising:

[0008] Combustion chamber head;

[0009] A flame tube, the flame tube is integrally connected to the combustion chamber head, and an igniter is arranged inside the flame tube;

[0010] A bluff body, wherein the bluff body is arranged inside the flame tube;

[0011] Also includes:

[0012] A fuel premixing structure, wherein the fuel premixing structure is arranged at the head of the combustion chamber and an outlet of the fuel premixing structure is connected to the flame tube, and the fuel premixing structure is suitable for premixing the fuel to be burned;

[0013] A cooling medium injection structure is arranged inside the bluff body and is suitable for injecting cooling medium in the reverse direction of the fuel premixing structure to discharge the fuel, so as to reduce the front temperature of the flame surface in the flame tube, thereby reducing the generation of thermal nitrogen oxides.

[0014] To further optimize the technical solution, the cooling medium injection structure includes:

[0015] A cooling medium supply cavity, wherein the cooling medium supply cavity is arranged inside the bluff body, and a plurality of injection holes communicating with the cooling medium supply cavity are opened on the surface of the bluff body;

[0016] A cooling medium connecting pipe is connected to the cooling medium supply chamber and an end of the cooling medium connecting pipe extends from the flame tube and is connected to a cooling medium source.

[0017] To further optimize the technical solution, a plurality of cooling medium connecting pipes are provided and evenly distributed along the circumference of the flame tube, each cooling medium connecting pipe extends out of the flame tube and is respectively connected to a cooling medium loop, and the cooling medium loop is connected to a cooling medium source.

[0018] The technical solution is further optimized, and the combustion chamber is suitable for the combustion of hydrogen.

[0019] Further optimizing the technical solution, the fuel premixing structure includes:

[0020] A plurality of main combustion premixing nozzles, the main combustion premixing nozzles are evenly arranged in the combustion chamber head in the circumferential direction, the main combustion premixing nozzles are suitable for multi-stage premixing of hydrogen and discharging the premixed hydrogen into the flame tube;

[0021] A diffusion service nozzle is arranged in the head of the combustion chamber, and is suitable for diffusing the service hydrogen into the interior of the flame tube.

[0022] Further optimizing the technical solution, the main combustion premixing nozzle includes:

[0023] A premixed air supply pipe, the end of which is connected to the flame tube;

[0024] A premixed hydrogen supply pipe, wherein the premixed hydrogen supply pipe is sleeved inside the premixed air supply pipe, one end of the premixed hydrogen supply pipe is connected to a premixed hydrogen source, and the other end of the premixed hydrogen supply pipe is open and located inside the premixed air supply pipe;

[0025] A premixed air supply chamber connected to a premixed air source is formed between the premixed hydrogen supply pipe and the premixed air supply pipe.

[0026] To further optimize the technical solution, a premixed hydrogen supply chamber and a premixed hydrogen supply chamber are provided in the premixed hydrogen supply pipe. The premixed hydrogen supply chamber is an annular channel and is provided with a plurality of hydrogen premixing holes connected to the premixed air supply chamber.

[0027] To further optimize the technical solution, the middle section of the premixed hydrogen supply pipe is provided with a wedge-shaped structure suitable for rectifying and accelerating the air flow;

[0028] and / or the premixed air supply pipe is arranged as a contraction structure;

[0029] And / or the combustion chamber head is in a contracted shape.

[0030] To further optimize the technical solution, the diffusion duty nozzle includes:

[0031] A duty nozzle, wherein a duty hydrogen supply pipe connected to the duty hydrogen and a diffusion air supply pipe connected to the diffusion air source are arranged inside the duty nozzle, and the diffusion air supply pipe is provided with at least one stage, and the duty hydrogen discharged from the duty hydrogen supply pipe and the diffusion air discharged from the diffusion air supply pipe are mixed at the duty nozzle outlet;

[0032] At least one stage of cyclone, each of the diffused air supply pipes is provided with a cyclone;

[0033] A venturi device is connected to the service nozzle and is placed inside the flame tube.

[0034] To further optimize the technical solution, a transition section is provided between the main combustion premixing nozzle and the flame tube, an air intake grille is provided between the duty nozzle and the transition section, and a plurality of evenly distributed through holes are provided on the air intake grille.

[0035] The technical solution is further optimized, the blunt body includes a blunt body front end and a blunt body rear end, the blunt body front end is conical, and the blunt body rear end is rectangular; the inner side of the blunt body front end is the blunt body inner turbulence zone, and the outer side of the blunt body front end is the blunt body outer turbulence zone; when the premixed gas propagates to the blunt body front end, it is split, one part flows into the blunt body inner turbulence zone for combustion, and the other part flows into the blunt body outer turbulence zone and flows along the outer surface of the blunt body to the blunt body rear end.

[0036] To further optimize the technical solution, a secondary hydrogen supply structure suitable for supplying secondary hydrogen to the flame tube located at the rear end of the bluff body is also provided inside the bluff body; and a plurality of secondary air supply holes are opened on the side wall of the flame tube located at the rear end of the bluff body.

[0037] To further optimize the technical solution, the side wall of the flame tube at the rear end of the bluff body is provided with:

[0038] A plurality of cooling holes, wherein the cooling holes are suitable for cooling the wall surface of the flame tube;

[0039] And / or a plurality of mixing holes, each of the mixing holes is uniformly arranged on the side wall of the flame tube in a circumferential direction, and the mixing holes are suitable for adjusting the temperature distribution of the flame tube outlet to make the flame tube outlet temperature more uniform.

[0040] A gas turbine comprises a rotor, a compressor, a turbine and the combustion chamber, wherein the compressor and the turbine are both mounted on the rotor, the air outlet end of the compressor is connected to the air inlet end of the combustion chamber, and the air outlet end of the combustion chamber is connected to the air inlet end of the turbine.

[0041] The technical solution of the present invention has the following advantages:

[0042] 1. The combustion chamber provided by the present invention adopts a combination of high-speed injection of premixed fuel gas and a blunt body, which can make the premixed gas of hydrogen and air burn in a reasonable design area, and can make hydrogen stably premixed and burned in the combustion chamber, thereby significantly reducing carbon emissions; and by spraying a cooling medium into the flame tube, the front temperature of the diffusion combustion flame surface downstream of the service nozzle in the fuel premixing structure can be reduced, thereby significantly reducing the generation of thermal nitrogen oxides, reducing pollutant emissions, and reducing the degree of pollution to the environment.

[0043] 2. In the combustion chamber provided by the present invention, the hydrogen supply cavity can spray secondary hydrogen behind the bluff body through the secondary hydrogen supply hole, and cool the rear end of the bluff body at the same time. The secondary hydrogen is quickly mixed with the secondary air introduced from the secondary air supply hole and then diffused and burned, which can improve the situation where there is no combustion or even no airflow organization in some areas behind the bluff body due to the obstruction of the bluff body, and can effectively improve the flow field structure in the flame tube and the temperature distribution at the combustion chamber outlet.

[0044] 3. The combustion chamber provided by the present invention has a combustion chamber head that contracts from the front end to the rear end, and / or a wedge-shaped structure is provided in the middle section of the premixed hydrogen supply pipe, and / or the premixed air supply pipe and the premixed hydrogen supply pipe are provided with a contraction structure. Through the above structure, the premixed fuel gas flows out of the transition section at an extremely fast speed, which is much higher than the propagation speed of the hydrogen flame so that it cannot be stationary and burn, thereby ensuring that the premixed fuel gas will not burn in the fast propagation area, preventing backfire, and enabling the present invention to achieve premixed combustion using hydrogen as fuel.

[0045] 4. The combustion chamber provided by the present invention is provided with at least one stage of swirlers, and the swirlers have opposite rotation directions, which can generate a reasonable reflow zone downstream of the service nozzle.

[0046] 5. In the combustion chamber provided by the present invention, an air intake grille is provided between the duty nozzle and the transition section, and a plurality of evenly distributed through holes are provided on the air intake grille. The through holes can convey air to the flame tube to participate in combustion, and cool the Venturi device before combustion to reduce its wall temperature.

[0047] 6. In the combustion chamber provided by the present invention, air propagates downstream at high speed in the premixed air supply chamber, and hydrogen in the premixed hydrogen auxiliary supply chamber and the premixed hydrogen main supply chamber also propagates downstream at high speed. Part of the hydrogen in the premixed hydrogen auxiliary supply chamber is transmitted from the hydrogen premixing hole, enters the premixed air supply chamber and mixes with the air once, and then the mixed gas continues to propagate downstream until it propagates to the outlet of the premixed hydrogen supply pipe, and then it is mixed with the hydrogen in the premixed hydrogen main supply chamber and the remaining hydrogen in the premixed hydrogen auxiliary supply chamber for a second time, which can improve the mixing efficiency and ensure the efficiency of the gas turbine. The premixed gas after uniform mixing enters the flame tube through the transition section. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0049] Figure 1 It is a schematic structural diagram of the combustion chamber of the present invention.

[0050] Figure 2 It is an axial cross-sectional view of the combustion chamber of the present invention.

[0051] Figure 3 It is a left side view of the combustion chamber of the present invention.

[0052] Figure 4 For the present invention Figure 3 A partial enlarged view of point C in the middle.

[0053] Figure 5 It is a front view of the combustion chamber of the present invention.

[0054] Figure 6 For the present invention Figure 5 Section A-A in the middle.

[0055] Figure 7 For the present invention Figure 5 Middle B-B section.

[0056] Figure 8 It is a schematic diagram of the flow of part of air and hydrogen in the combustion chamber of the present invention.

[0057] Fig. 9It is a schematic diagram of the flow field structure and distribution in the combustion chamber of the present invention.

[0058] Reference numerals:

[0059] 1. Combustion chamber head, 2. Premixed air supply pipe, 3. Premixed air supply cavity, 4. Premixed hydrogen supply pipe, 5. Premixed hydrogen auxiliary supply cavity, 6. Premixed hydrogen main supply cavity, 7. Hydrogen premixing hole, 8. Transition section, 9. Duty nozzle, 10. Secondary diffusion air supply cavity, 11. Primary diffusion air supply cavity, 12. Duty hydrogen supply cavity, 13. Secondary cyclone, 14. Primary cyclone, 15. Venturi device, 16. Inlet grille, 17. Blunt body, 18. Cooling medium ring Road, 19. Cooling medium connecting pipe, 20. Cooling medium supply chamber, 21. Injection hole, 22. Hydrogen supply loop, 23. Hydrogen supply connecting pipe, 24. Hydrogen supply chamber, 25. Secondary hydrogen supply hole, 26. Secondary air supply hole, 27. Cooling hole, 28. Mixing hole, 29. Flame tube, 30. Primary premixing zone, 31. Secondary premixing zone, 32. Rapid propagation zone, 33. Blunt body inner turbulence zone, 34. Blunt body outer turbulence zone, 35. Secondary diffusion combustion zone, 36. Duty flame combustion zone. DETAILED DESCRIPTION

[0060] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0062] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0063] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0064] Example 1

[0065] like Figures 1 to 9 As shown, this embodiment discloses a combustion chamber, including a combustion chamber head 1, a flame tube 29, a bluff body 17, a fuel premixing structure and a cooling medium injection structure.

[0066] The flame tube 29 is integrally connected to the combustion chamber head 1. An igniter is provided inside the flame tube 29, and the fuel inside the flame tube 29 is ignited by the igniter.

[0067] The bluff bodies 17 are evenly arranged inside the flame tube 29 to guide and divert the fuel and reduce the gas flow rate.

[0068] The fuel premixing structure is arranged at the combustion chamber head 1 and the outlet is connected to the flame tube 29. The fuel premixing structure is suitable for premixing the fuel to be burned.

[0069] The cooling medium injection structure is arranged inside the bluff body 17, and is suitable for injecting cooling medium in the reverse direction of the fuel premixing structure to discharge the fuel, so as to reduce the flame front temperature in the flame tube 29, thereby reducing the generation of thermal nitrogen oxides.

[0070] The above-mentioned combustion chamber adopts a combination of high-speed injection of premixed fuel gas and a blunt body, which can make the premixed gas of hydrogen and air burn in a reasonable design area and avoid backfire, so that hydrogen can be stably premixed and burned in the combustion chamber, significantly reducing carbon emissions; the combustion temperature of hydrogen is relatively high, so a cooling medium injection structure is provided inside the blunt body 17, and the front temperature of the diffusion combustion flame surface downstream of the service nozzle in the fuel premixing structure can be reduced by injecting a cooling medium into the flame tube 29, thereby significantly reducing the generation of thermal nitrogen oxides, reducing pollutant emissions, and reducing the degree of pollution to the environment.

[0071] As a specific embodiment, the cooling medium injection structure includes a cooling medium supply chamber 20 and a cooling medium connecting pipe 19. The cooling medium supply chamber 20 is arranged inside the bluff 17, and a plurality of injection holes 21 connected to the cooling medium supply chamber 20 are provided on the surface of the bluff 17, and a high temperature resistant pressure nozzle is provided on the injection hole 21. The cooling medium connecting pipe 19 is connected to the cooling medium supply chamber 20, and the end of the cooling medium connecting pipe 19 extends from the flame tube 29 and is connected to the cooling medium source. The cooling medium discharged from the cooling medium source in this embodiment is transported to the cooling medium connecting pipe 19, and is transported to the cooling medium supply chamber 20 through the cooling medium connecting pipe 19, and is ejected in the opposite direction of the fuel discharged from the fuel premixing structure through the injection hole, thereby effectively reducing the front temperature of the combustion flame surface.

[0072] The cooling medium in this embodiment is cooling water, but other media may also be used, which is not limited here.

[0073] The cooling medium supply cavity 20 is annular, and its cross-sectional shape is the same as the front end of the bluff body 17, which can increase the cooling area and reduce the wall temperature of the front end of the bluff body.

[0074] A plurality of cooling medium connecting pipes 19 are provided and evenly distributed along the circumference of the flame tube 29. Each cooling medium connecting pipe 19 extends out of the flame tube 29 and is respectively connected to the cooling medium loop 18, and the cooling medium loop 18 is connected to the cooling medium source. In this embodiment, the cooling medium supply cavity 20 is supplied with cooling medium through a plurality of cooling medium connecting pipes 19 evenly arranged circumferentially, so that the amount of cooling medium introduced along the circumference of the cooling medium supply cavity 20 is more uniform. The cooling medium loop 18 can supply cooling water to the cooling medium supply cavity 20 through the cooling medium connecting pipe 19. Then the cooling water is sprayed to the flame front of the duty diffusion combustion flame through the spray hole 21 to reduce the flame front temperature and reduce the generation of nitrogen oxides.

[0075] The combustion chamber is suitable for the combustion of hydrogen, that is, the present invention adopts the method of premixing hydrogen and air before combustion.

[0076] As a specific implementation, the fuel premixing structure includes a main combustion premixing nozzle and a diffusion service nozzle. There are a plurality of main combustion premixing nozzles, which are evenly arranged in the combustion chamber head 1 in the circumferential direction. The main combustion premixing nozzle is suitable for multi-stage premixing of hydrogen and discharging the premixed hydrogen into the flame tube 29. More specifically, 8 sets of main combustion premixing nozzles are provided in this embodiment. The diffusion service nozzle is arranged in the combustion chamber head 1, and the diffusion service nozzle is suitable for diffusing the service hydrogen into the flame tube 29.

[0077] The main combustion premixing nozzle includes a premixed air supply pipe 2 and a premixed hydrogen supply pipe 4. The end of the premixed air supply pipe 2 is connected to the flame tube 29. The premixed hydrogen supply pipe 4 is sleeved inside the premixed air supply pipe 2, one end of the premixed hydrogen supply pipe 4 is connected to the premixed hydrogen source, and the other end of the premixed hydrogen supply pipe 4 is open and located inside the premixed air supply pipe 2. A premixed air supply chamber 3 is formed between the premixed hydrogen supply pipe 4 and the premixed air supply pipe 2. The premixed air supply chamber 3 is an annular chamber, and the premixed air supply chamber 3 is connected to the premixed air source for supplying high-pressure air required for premixed combustion. The premixed hydrogen source in this embodiment inputs hydrogen to the premixed hydrogen supply pipe 4, and inputs high-pressure air to the premixed air supply pipe 2 through the premixed air source. The hydrogen discharged from the end of the premixed hydrogen supply pipe 4 is mixed with the high-pressure air inside the premixed air supply chamber 3, and the premixed gas is discharged into the flame tube 29.

[0078] As a further improved implementation, the combustion chamber head 1 is contracted from the front end to the rear end, which is used to accelerate the flow of air. And / or the middle section of the premixed hydrogen supply pipe 4 is provided with a wedge-shaped structure, the middle section of the wedge-shaped structure is expanded, and the front and rear sections of the wedge-shaped structure are contracted, which is suitable for rectifying and accelerating the air flow, thereby increasing the gas flow rate entering the flame tube 29. And / or the premixed air supply pipe 2 and the premixed hydrogen supply pipe 4 are set as contraction structures, which achieves the purpose of accelerating the gas flow. Through the above structure, the speed of the premixed fuel gas flowing out of the transition section 8 is extremely fast, which is much higher than the propagation speed of the hydrogen flame so that it cannot be stationary and burned, thereby ensuring that the hydrogen will not burn in the fast propagation area 32 to prevent backfire.

[0079] As a further improved implementation, a premixed hydrogen supply chamber 5 and a premixed hydrogen main supply chamber 6 are provided in the premixed hydrogen supply pipe 4. The premixed hydrogen supply chamber 5 is an annular channel and is provided with a plurality of hydrogen premixing holes 7 connected to the premixed air supply chamber 3. More specifically, the hydrogen premixing holes 7 are provided on the premixed hydrogen supply pipe 4 located downstream of the wedge-shaped structure, and are provided in two rows. The premixed hydrogen source in this embodiment can supply hydrogen to the premixed hydrogen supply chamber 5 and the premixed hydrogen main supply chamber 6 at the same time. The hydrogen supplied by the premixed hydrogen auxiliary supply chamber 5 can be first discharged into the premixed air supply chamber 3 through the hydrogen premixing hole 7 to be premixed with the air that has been accelerated once. The remaining part of the hydrogen in the premixed hydrogen auxiliary supply chamber 5 is transmitted from the outlet downstream of the premixed hydrogen auxiliary supply chamber 5. The hydrogen transmitted from the premixed hydrogen main supply chamber 6 and part of the hydrogen transmitted from the outlet downstream of the premixed hydrogen auxiliary supply chamber 5 are mixed with the primary mixed gas again and propagated to the downstream of the premixed air supply pipe 2. The hydrogen is input into the premixed air supply chamber 3 through the opening at the end of the premixed hydrogen main supply chamber 6 to be premixed with the air again. The gas after multiple premixing is discharged into the flame tube 29 through the transition section 8.

[0080] The cross section of the premixed hydrogen main supply chamber 6 is circular, and the end is contracted, which is used to accelerate the hydrogen.

[0081] The diffusion service nozzle comprises a service nozzle 9 , a swirler and a Venturi device 15 .

[0082] The service nozzle 9 is provided with a service hydrogen supply pipe connected to the service hydrogen and a diffusion air supply pipe connected to the diffusion air source. The central part of the service hydrogen supply pipe is the service hydrogen supply chamber 12, and a plurality of hydrogen holes are provided at the end of the service hydrogen supply chamber 12 for conveying hydrogen to the flame tube 29. The diffusion air supply pipe is provided with at least one stage, and the service hydrogen discharged from the service hydrogen supply pipe and the diffusion air discharged from the diffusion air supply pipe are mixed at the outlet of the service nozzle 9.

[0083] The cyclone is provided with at least one stage, more specifically, two stages of cyclones are provided in this embodiment, namely, the primary cyclone 14 and the secondary cyclone 13, and a cyclone is provided in each diffusion air supply pipe. The secondary cyclone 13 is evenly distributed along the circumference in the secondary diffusion air supply chamber 10, and the primary cyclone 14 is evenly distributed along the circumference in the primary diffusion air supply chamber 11. The two stages of cyclones have opposite rotation directions, and a reasonable recirculation zone can be generated downstream of the duty nozzle 9.

[0084] The Venturi device 15 is connected to the service nozzle 9 and is placed inside the flame tube 29. The Venturi device 15 is beneficial to the formation of the reflow zone and the stabilization of the flame.

[0085] The above-mentioned diffusion duty nozzle uses a double-stage swirler inside and adopts a Venturi device 15, which is conducive to the formation of the reflow zone and flame stabilization, and stabilizes the reflow zone on the inner side of the bluff body 17.

[0086] As a further improved implementation, an air intake grille 16 is provided between the service nozzle 9 and the transition section 8. The air intake grille 16 is provided with a number of evenly distributed through holes for air circulation. The through holes can transport air to the flame tube 29 to participate in combustion, and cool the Venturi device 15 before combustion to reduce its wall temperature.

[0087] In the above-mentioned fuel premixing structure, the air and hydrogen required in the main combustion premixing nozzle are supplied by separate pipelines to ensure that the supply pressure and flow rate are high enough. The air required in the diffusion duty nozzle is provided by the compressor. After the air is transmitted from the compressor outlet, it enters the guide sleeve through the combustion and compression cylinder, and then flows from the tail to the head of the combustion chamber, and finally enters the combustion chamber head 1, and enters the flame tube 29 through the secondary diffusion air supply cavity 10, the primary diffusion air supply cavity 11, the air intake grille 16 and the bypass between the combustion chamber head 1 and the premixing air supply pipe 2.

[0088] A transition section 8 is arranged between the main combustion premixing nozzle and the flame tube 29. The transition section 8 is a circular-to-square structure, and there are 8 of them in total. The circular inlet is connected to the outlet of the premixed air supply pipe 2, and the square outlet is evenly distributed along the circumference at the end of the combustion chamber head 1, which plays a guiding role and can reasonably distribute the flow field structure so that the high-speed mixed air can be evenly propagated to the front of the blunt body 17.

[0089] As a specific implementation, the bluff body 17 includes a bluff body front end and a bluff body rear end, the bluff body front end is conical, and the bluff body rear end is rectangular and rounded to reduce fuel flow loss. The inner side of the bluff body front end is the bluff body inner turbulence zone 33, and the outer side of the bluff body front end is the bluff body outer turbulence zone 34; when the premixed gas propagates to the bluff body front end, a part of it flows into the bluff body inner turbulence zone 33 for combustion, and the other part flows into the bluff body outer turbulence zone 34 and flows along the outer surface of the bluff body 17 to the bluff body rear end.

[0090] The front end of the bluff body includes an inner side and an outer side, the inner side is close to its axis, and the injection hole 21 is arranged on the inner side. The length and cone angle of the inner side and the outer side can be appropriately adjusted according to the working conditions such as the combustion chamber flow rate and the airflow organization effect. The mixed gas is divided and the flow velocity is reduced at the front end of the bluff body. A part of it flows from the outer side of the front end of the bluff body in the direction away from the axis and flows to the rear end of the bluff body to participate in the combustion. The other part flows from the inner side of the front end of the bluff body toward the axis and is ignited by the duty flame.

[0091] As a further improved implementation, a secondary hydrogen supply structure suitable for supplying secondary hydrogen to a flame tube 29 located at the rear end of the bluff body is further provided inside the bluff body 17. A plurality of secondary air supply holes 26 are provided on the side wall of the flame tube 29 located at the rear end of the bluff body. The secondary air supply holes 26 are connected to the compressor, and the air source can introduce air into the flame tube. The air generated by the compressor is mixed with the secondary hydrogen, and the hydrogen and air diffuse and burn behind the bluff body 17, thereby improving the flow field structure and temperature distribution in the flame tube 29.

[0092] The secondary hydrogen supply structure includes a hydrogen supply connecting pipe 23, a hydrogen supply loop 22, and a hydrogen supply chamber 24. The hydrogen supply chamber 24 is arranged inside the bluff body 17 and is located at the rear end of the bluff body 17. The hydrogen supply chamber 24 is annular and has a rectangular cross section. A plurality of secondary hydrogen supply holes 25 are provided at the rear end of the hydrogen supply chamber 24. The secondary hydrogen supply holes 25 may be provided with pressure nozzles according to the use requirements. The hydrogen supply connecting pipe 23 is arranged on the bluff body 17 and is connected to the hydrogen supply chamber 24. The hydrogen supply connecting pipe 23 partially extends out of the flame tube. There are a plurality of hydrogen supply connecting pipes 23 evenly distributed along the circumference of the flame tube, so that the hydrogen input to the hydrogen supply chamber 24 is more evenly distributed. The hydrogen supply loop 22 is connected to each hydrogen supply connecting pipe 23 and is circumferentially arranged on the periphery of the flame tube. The hydrogen supply loop 22 is connected to a hydrogen source, which can discharge hydrogen into the hydrogen supply loop 22, the hydrogen supply connecting pipe 23 and the hydrogen supply chamber 24, and then discharge it into the interior of the flame tube through the secondary hydrogen supply hole 25 on the hydrogen supply chamber 24.

[0093] Specifically, there are 8 cooling medium connecting pipes 19 and 8 hydrogen supply connecting pipes 23 , corresponding to the main combustion premixing nozzles, and the 8 pipes simultaneously inject water and secondary hydrogen into the cooling medium supply chamber 20 and the hydrogen supply chamber 24 .

[0094] In the above-mentioned secondary hydrogen supply structure, the secondary hydrogen flows in the hydrogen supply cavity 24, cools the rear end wall of the bluff body, and can preheat the secondary hydrogen while absorbing heat, thereby reducing the secondary hydrogen consumption and improving the combustion efficiency. The preheated hydrogen is transmitted from the secondary hydrogen supply hole 25 to the downstream of the bluff body 17 to participate in the combustion.

[0095] The cooling medium loop 18 and the hydrogen supply loop 22 are coaxially arranged with the flame tube 29, the bluff body 17 and the service nozzle 9 respectively.

[0096] As a further improved implementation, a cooling hole 27 is provided on the side wall of the flame tube 29 at the rear end of the bluff body. A plurality of cooling holes 27 are provided, and the cooling holes 27 are suitable for cooling the wall surface of the flame tube 29 and reducing the wall surface temperature of the flame tube 29.

[0097] And / or a mixing hole 28 is provided on the side wall of the flame tube 29 located at the rear end of the bluff body, and a plurality of mixing holes 28 are provided, and each mixing hole 28 is evenly arranged on the side wall of the flame tube 29 in a circumferential direction, and the mixing holes 28 are suitable for adjusting the temperature distribution at the combustion chamber outlet to make the combustion chamber outlet temperature more uniform.

[0098] The required flow rates and flow rates of the premixed air supply chamber 3, the premixed hydrogen main supply chamber 6, the premixed hydrogen auxiliary supply chamber 5 and the duty hydrogen supply chamber 12 in the present invention all support independent adjustment.

[0099] like Fig. 9 As shown, in the premixed air supply chamber 3, the outlet of the hydrogen premixing hole 7 is the primary premixing zone 30, where part of the hydrogen and air are mixed for the first time. Between the outlet of the premixed hydrogen supply pipe 4 and the transition section 8 is the secondary premixing zone 31, where all hydrogen and air are premixed; between the transition section 8 and the blunt body 17 is the rapid propagation zone 32, where the mixed gas propagates rapidly and cannot be stationary for combustion. The inside of the blunt body 17 is the turbulent flow zone 33 inside the blunt body, and the outside of the blunt body 17 is the turbulent flow zone 34 outside the blunt body. When the mixed gas propagates to the front end of the blunt body 17, part of it flows into the turbulent flow zone 33 inside the blunt body, and the rest flows into the turbulent flow zone 34 outside the blunt body. Behind the blunt body 17 is the secondary diffusion combustion zone 35, where the secondary hydrogen is mixed with the secondary air flowing in from the secondary air supply hole 26 and diffusely burns. Downstream of the duty nozzle 9 is the duty flame combustion zone 36, which can generate a swirl zone to stabilize the flame.

[0100] The working process of the present invention is as follows:

[0101] The hydrogen required by the diffusion duty nozzle is supplied separately by the corresponding pipeline, and the air is provided by the compressor. After the hydrogen enters the duty hydrogen supply chamber 12, it is transported to the venturi device 15 through the hydrogen hole at its end. At the same time, after the air is transmitted from the compressor outlet, it enters the guide bushing through the combustion and compression cylinder, flows from the tail of the combustion chamber to the head of the combustion chamber 1, and then enters the primary diffusion air supply chamber 11 and the secondary diffusion air supply chamber 10 respectively. After flowing through the two-stage cyclone, it is transmitted from the outlet and quickly mixed with the hydrogen. After being evenly mixed, it is transmitted to the flame tube 29 and ignited by the igniter to form the duty flame.

[0102] The hydrogen and air required by the main combustion premixing nozzle are supplied separately by the corresponding pipelines. The air propagates downstream at high speed in the premixed air supply chamber 3. At the same time, the hydrogen in the premixed hydrogen auxiliary supply chamber 5 and the premixed hydrogen main supply chamber 6 also propagates downstream at high speed. Among them, part of the hydrogen in the premixed hydrogen auxiliary supply chamber 5 is transmitted from the hydrogen premixing hole 7, enters the premixed air supply chamber 3 and mixes with the air once, and then the mixed gas continues to propagate downstream until it propagates to the outlet of the premixed hydrogen supply pipe 4, and then it is mixed with the hydrogen in the premixed hydrogen main supply chamber 6 and the remaining hydrogen in the premixed hydrogen auxiliary supply chamber 5 for a second time, which can improve the mixing efficiency. The premixed gas after uniform mixing enters the flame tube 29 through the transition section 8.

[0103] In the flame tube 29, the premixed gas first passes through the fast propagation zone 32, in which the propagation speed of the premixed gas is so fast that it cannot be stationary and burn; when it propagates to the front of the bluff body 17, it is diverted and decelerated by the front end structure of the bluff body 17, so that the flow speed of the premixed gas is equivalent to the flame propagation speed, a part of it flows to the turbulence zone 33 inside the bluff body, and is ignited and burned by the duty flame in this area, and the other part flows to the turbulence zone 34 outside the bluff body, and flows along the outer surface of the bluff body 17 to the rear end of the bluff body 17, and participates in the combustion at the rear end of the bluff body. The injection hole 21 can spray water to the flame front in the duty flame combustion zone 36 to reduce the flame front temperature, thereby reducing the generation of thermal nitrogen oxides and cooling the front end of the bluff body 17 at the same time; the secondary hydrogen supply hole 25 can spray secondary hydrogen behind the bluff body 17 and cool the rear end of the bluff body 17 at the same time, and the secondary hydrogen is quickly mixed with the secondary air introduced from the secondary air supply hole 26 and then diffused and burned, which can improve the situation where there is no combustion or even no airflow organization in some areas behind the bluff body 17 due to the obstruction of the bluff body 17, and can effectively improve the flow field structure in the flame tube 29 and the temperature distribution at the combustion chamber outlet.

[0104] The present invention can also use the following method to supplement the air required for combustion: air is supplemented from the air intake grille 16, the supplemented air first cools the venturi device 15, then quickly mixes with the premixed gas and propagates downstream, and finally participates in combustion. An air bypass can also be provided between the combustion chamber head 1 and the premixed air supply pipe 2, and the air from the compressor can enter the flame tube 29 through the bypass to participate in combustion, thereby supplementing the air required for hydrogen combustion.

[0105] Example 2

[0106] This embodiment discloses a gas turbine, comprising a rotor, a compressor, a turbine and the combustion chamber of Embodiment 1. The compressor and the turbine are both mounted on the rotor, the air outlet of the compressor is connected to the air inlet of the combustion chamber, and the air outlet of the combustion chamber is connected to the air inlet of the turbine.

[0107] The above-mentioned gas turbine, through reasonable development and improvement of the overall structure of the combustion chamber, enables the gas turbine to achieve premixed combustion with hydrogen as fuel while avoiding backfire, thereby ensuring the efficiency of the gas turbine and reducing carbon emissions.

[0108] Obviously, the above embodiments are merely examples for clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from them are still within the protection scope of the invention.

Claims

1. Combustion chamber, including: Combustion chamber head (1); A flame tube (29), the flame tube (29) being integrally connected to the combustion chamber head (1), and an igniter being arranged inside the flame tube (29); A bluff body (17), wherein the bluff body (17) is arranged inside the flame tube (29); It is characterized by further comprising: A fuel premixing structure, wherein the fuel premixing structure is arranged in the combustion chamber head (1) and the outlet is connected to the flame tube (29), and the fuel premixing structure is suitable for premixing the fuel to be burned; the fuel premixing structure includes a diffusion service nozzle and a plurality of main combustion premixing nozzles; the main combustion premixing nozzles are uniformly arranged in the combustion chamber head (1) in the circumferential direction, and the main combustion premixing nozzles are suitable for multi-stage premixing of hydrogen and discharging the premixed hydrogen into the flame tube (29); the diffusion service nozzle is arranged in the combustion chamber head (1), and the diffusion service nozzle is suitable for diffusing the service hydrogen into the flame tube (29); A cooling medium injection structure is arranged inside the bluff body (17), and is suitable for injecting cooling medium in the reverse direction of the fuel discharge from the fuel premixing structure to reduce the flame front temperature in the flame tube (29), thereby reducing the generation of thermal nitrogen oxides.

2. The combustion chamber according to claim 1, characterized in that The cooling medium injection structure comprises: A cooling medium supply cavity (20), the cooling medium supply cavity (20) being arranged inside the bluff body (17), and a plurality of injection holes communicating with the cooling medium supply cavity (20) being opened on the surface of the bluff body (17); A cooling medium connecting pipe (19), wherein the cooling medium connecting pipe (19) is connected to the cooling medium supply chamber (20) and an end portion thereof extends out from the flame tube (29) and is connected to a cooling medium source.

3. The combustion chamber according to claim 2, characterized in that A plurality of cooling medium connecting pipes (19) are provided and are evenly distributed along the circumference of the flame tube (29). Each cooling medium connecting pipe (19) extends out of the flame tube (29) and is respectively connected to a cooling medium loop (18). The cooling medium loop (18) is connected to a cooling medium source.

4. The combustion chamber according to any one of claims 1 to 3, characterized in that The combustion chamber is suitable for the combustion of hydrogen.

5. The combustion chamber according to claim 4, characterized in that The main combustion premixing nozzle comprises: A premixed air supply pipe (2), the end of which is connected to the flame tube (29); a premixed hydrogen supply pipe (4), the premixed hydrogen supply pipe (4) being sleeved inside the premixed air supply pipe (2), one end of the premixed hydrogen supply pipe (4) being connected to a premixed hydrogen source, and the other end of the premixed hydrogen supply pipe (4) being open and located inside the premixed air supply pipe (2); A premixed air supply chamber (3) connected to a premixed air source is formed between the premixed hydrogen supply pipe (4) and the premixed air supply pipe (2).

6. The combustion chamber according to claim 5, characterized in that The premixed hydrogen supply pipe (4) is provided with a premixed hydrogen secondary supply chamber (5) and a premixed hydrogen main supply chamber (6); the premixed hydrogen secondary supply chamber (5) is an annular channel and is provided with a plurality of hydrogen premixing holes (7) which are connected to the premixed air supply chamber (3).

7. The combustion chamber according to claim 5, characterized in that The middle section of the premixed hydrogen supply pipe (4) is provided with a wedge-shaped structure suitable for rectifying and accelerating the flow of air; and / or the premixed air supply pipe (2) is configured as a contraction structure; And / or the combustion chamber head (1) is in a contracted shape.

8. The combustion chamber according to claim 4, characterized in that The diffusion duty nozzle comprises: A duty nozzle (9), wherein a duty hydrogen supply pipe connected to the duty hydrogen and a diffusion air supply pipe connected to the diffusion air source are arranged inside the duty nozzle (9), and the diffusion air supply pipe is provided with at least one stage, and the duty hydrogen discharged from the duty hydrogen supply pipe and the diffusion air discharged from the diffusion air supply pipe are mixed at the outlet of the duty nozzle (9); At least one stage of cyclone, each of the diffused air supply pipes is provided with a cyclone; A venturi device (15) is connected to the service nozzle (9) and is placed inside the flame tube (29).

9. The combustion chamber according to claim 8, characterized in that A transition section (8) is provided between the main combustion premixing nozzle and the flame tube (29), an air intake grille (16) is provided between the duty nozzle (9) and the transition section (8), and the air intake grille (16) is provided with a plurality of evenly distributed through holes.

10. The combustion chamber according to claim 4, characterized in that The bluff body (17) comprises a bluff body front end and a bluff body rear end, the bluff body front end is conical, and the bluff body rear end is rectangular; the inner side of the bluff body front end is a bluff body inner turbulence zone (33), and the outer side of the bluff body front end is a bluff body outer turbulence zone (34); when the premixed gas propagates to the bluff body front end, a part of the premixed gas flows into the bluff body inner turbulence zone (33) for combustion, and the other part flows into the bluff body outer turbulence zone (34) and flows along the outer surface of the bluff body (17) to the bluff body rear end.

11. The combustion chamber according to claim 10, characterized in that The bluff body (17) is also provided with a secondary hydrogen supply structure suitable for supplying secondary hydrogen to a flame tube (29) located at the rear end of the bluff body; a plurality of secondary air supply holes (26) are provided on the side wall of the flame tube (29) located at the rear end of the bluff body.

12. The combustion chamber according to claim 10, characterized in that The side wall of the flame tube (29) at the rear end of the bluff body is provided with: A plurality of cooling holes (27), wherein the cooling holes (27) are suitable for cooling the wall surface of the flame tube (29); and / or a plurality of mixing holes (28), each of the mixing holes (28) being uniformly arranged on the side wall of the flame tube (29) in a circumferential direction, and the mixing holes (28) being suitable for adjusting the temperature distribution at the outlet of the flame tube (29) so as to make the outlet temperature of the flame tube (29) more uniform.

13. A gas turbine, characterized in that It comprises a rotor, a compressor, a turbine and a combustion chamber as described in any one of claims 1 to 12, wherein the compressor and the turbine are both mounted on the rotor, the air outlet end of the compressor is connected to the air inlet end of the combustion chamber, and the air outlet end of the combustion chamber is connected to the air inlet end of the turbine.

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