Dual fuel lean premixed multi-stage swirl nozzle

Abstract

The present invention relates to the technical field of gas turbines and discloses a dual-fuel lean premixed multi-stage swirl nozzle, the dual-fuel lean premixed multi-stage swirl nozzle comprising a precombustion stage annular wall, a center rod and a main combustion stage annular wall, the precombustion stage annular wall having a precombustion stage channel penetrating in its length direction and a feed end and a discharge end arranged oppositely in its length direction; the center rod is arranged in the precombustion stage channel and extends from the feed end toward the discharge end, the center rod and the precombustion stage annular wall are spaced apart to form an annular cavity; the main combustion stage annular wall is arranged around the precombustion stage annular wall, the main combustion stage annular wall and the precombustion stage annular wall are spaced apart to form a main combustion stage annular channel. The dual-fuel lean premixed multi-stage swirl nozzle can realize real-time switching between gas fuel and liquid fuel, and can also control the required amount of gas fuel and liquid fuel according to the requirements of working conditions, thereby meeting different requirements of the combustion chamber.

Description

Technical Field

[0001] The invention relates to the technical field of gas turbines, and in particular to a dual-fuel lean premixed multi-stage swirl nozzle. Background Art

[0002] Dual-fuel gas turbines are widely used in the fields of petroleum, chemical industry, electric power and military due to their good fuel adaptability. The important premise of gas-liquid dual-fuel combustion technology is to achieve the switch between oil and gas without stopping the gas turbine, and to ensure that the performance of ignition / extinguishing, combustion stability, combustion efficiency, pollution emission, outlet temperature distribution, etc. can meet the design requirements.

[0003] Compared with the single-fuel combustion chamber, the design and development of the dual-fuel combustion chamber has the following design difficulties: ① Since it is necessary to realize the injection of two fuels and the mixing of fuel and air, this requires a more compact structure, and the gas and liquid fuel supply channels do not affect each other; ② The simultaneous satisfaction of the performance index requirements of the gas and liquid dual-fuel combustion chambers will result in a very narrow design boundary of the combustion chamber, and the difficulty of debugging will also increase; ③ The gas and liquid dual-fuel combustion chambers need to be consistent in the combustion organization mode, and both the liquid fuel nozzle and the gaseous fuel nozzle need to ensure that the fuel and air have a good mixing effect, and the distribution of the mixed gas is basically the same; ④ During the switching process between gas and liquid fuel in the dual-fuel combustion chamber, the combustion state is difficult to control, and a wider stable working boundary needs to be guaranteed. Therefore, the closing technology of the dual-fuel gas turbine combustion chamber lies in the design of the head solution.

[0004] In the related art, as the operating conditions improve, the problem of how to improve the combustion efficiency of gas fuel and liquid fuel needs to be solved urgently. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, an embodiment of the present invention proposes a dual-fuel lean premixed multi-stage swirl nozzle, which can realize real-time switching of gas fuel and liquid fuel, and can also control the injection amount of gas fuel and liquid fuel according to the requirements of working conditions, thereby meeting different requirements of the combustion chamber.

[0006] The dual-fuel lean premixed multi-stage swirl nozzle of the present invention comprises:

[0007] A pre-combustion stage annular wall, wherein the pre-combustion stage annular wall has a pre-combustion stage channel penetrating in the length direction thereof and a feed end and a discharge end arranged opposite to each other in the length direction thereof;

[0008] A center rod, the center rod is disposed in the pre-combustion stage channel and extends from the feed end toward the discharge end, the center rod and the pre-combustion stage annular wall are spaced apart to form an annular cavity;

[0009] a main combustion stage annular wall, the main combustion stage annular wall being arranged around the pre-combustion stage annular wall, the main combustion stage annular wall being spaced apart from the pre-combustion stage annular wall to form a main combustion stage annular channel;

[0010] Wherein, the central rod and / or the pre-combustion stage annular wall has a pre-liquid channel which is connected with the pre-combustion stage channel and sprays liquid fuel into the pre-combustion stage channel;

[0011] The central rod and / or the pre-combustion stage annular wall has a pre-gas passage that is in communication with the pre-combustion stage passage and injects gas fuel into the pre-combustion stage passage;

[0012] The pre-combustion stage annular wall and / or the main combustion stage annular wall has a main liquid channel which is in communication with the main combustion stage annular channel and injects the liquid fuel into the main combustion stage annular channel;

[0013] The pre-combustion stage annular wall and / or the main combustion stage annular wall have a main gas passage which is communicated with the main combustion stage annular passage and injects the gas fuel into the main combustion stage annular passage.

[0014] According to the multi-stage swirl nozzle of the present invention, the multi-stage swirl nozzle can realize the real-time switching of gas fuel and liquid fuel by controlling the operation of the pre-liquid channel, the pre-gas channel, the main liquid channel and the main gas channel, and can also realize the separate operation of gas fuel and liquid fuel, and can also realize the mixed operation of gas fuel and liquid fuel. At the same time, the demand for gas fuel and liquid fuel can also be controlled according to the requirements of the working conditions, so as to meet the different requirements of the combustion chamber. That is, when the working conditions are low, only the pre-liquid channel and the pre-gas channel can be allowed to work, so as to ensure that the combustion chamber has a stable combustion state. As the working conditions improve, the pre-liquid channel, the pre-gas channel, the main liquid channel and the main gas channel can be allowed to work at the same time, which can meet the requirements of higher working conditions.

[0015] Optionally, a plurality of pre-liquid communication ports are provided between the pre-combustion stage channel and the pre-liquid channel, and the plurality of pre-liquid communication ports are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall; and / or

[0016] A plurality of pre-gas communication openings are provided between the pre-combustion stage channel and the pre-liquid channel, and the plurality of pre-gas communication openings are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall; and / or

[0017] The main combustion stage annular channel and the main liquid channel are provided with a plurality of main liquid communication ports, and the plurality of main liquid communication ports are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall; and / or

[0018] A plurality of main gas communication ports are provided between the main combustion stage annular channel and the main gas channel, and the plurality of main gas communication ports are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall.

[0019] Optionally, the multi-stage swirl nozzle also includes: swirl blades, the swirl blades including pre-combustion stage blades arranged in the annular cavity and main combustion stage blades arranged in the main combustion stage annular channel, a pre-swirl flow channel is formed between the pre-combustion stage blades, the pre-combustion stage annular wall and the center rod, and a main swirl flow channel is formed between the main combustion stage blades, the pre-combustion stage annular wall and the main combustion stage annular wall.

[0020] Optionally, the pre-combustion stage blades are located between the feed end and the free end of the center rod in the length direction of the pre-combustion stage annular wall; and / or

[0021] The main combustion stage blades are located between the feed end and the free end of the central rod in the length direction of the pre-combustion stage annular wall; and / or

[0022] The pre-combustion stage blade and / or the main combustion stage blade are provided in plurality, and the plurality of pre-combustion stage blades and / or the plurality of main combustion stage blades are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall; and / or

[0023] The pre-liquid channel and / or the pre-gas channel are in communication with the pre-swirl flow channel; and / or

[0024] The main liquid channel and / or the main gas channel are communicated with the main swirl flow channel.

[0025] Optionally, a first annular convergent protrusion is provided on the inner wall surface of the pre-combustion stage annular wall and is located between the pre-combustion stage blades and the free end of the center rod in the length direction of the pre-combustion stage annular wall, and a protrusion distance of the first annular convergent protrusion gradually increases in the direction from the feed end to the discharge end; and / or

[0026] A second annular convergent protrusion is provided on the inner wall surface of the main combustion stage annular wall and / or the outer wall surface of the pre-combustion stage annular wall and is located between the main combustion stage blades and the end face of the discharge end in the length direction of the pre-combustion stage annular wall, and the protrusion distance of the second annular convergent protrusion gradually increases in the direction from the feed end to the discharge end.

[0027] Optionally, the position of the first annular convergent protrusion with the maximum protrusion distance is set to be the minimum pre-combustion stage channel cross-section, and the end surface of the free end of the center rod is flush with the minimum pre-combustion stage channel cross-section in the length direction of the pre-combustion stage annular wall.

[0028] Optionally, an annular expansion protrusion is provided on the inner wall surface of the pre-combustion stage annular wall and is located between the free end of the center rod and the end face of the discharge end in the length direction of the pre-combustion stage annular wall, and a protrusion distance of the annular expansion protrusion gradually decreases in the direction from the feed end to the discharge end, and the annular expansion protrusion is connected to the first annular convergence protrusion.

[0029] Optionally, the first annular convergent protrusion is provided with a first through hole extending in the length direction of the pre-combustion stage annular wall;

[0030] The annular expansion protrusion is provided with a cooling hole communicating with the first through hole; and / or

[0031] The pre-combustion stage annular wall has a cooling channel for introducing air, and the annular expansion protrusion is provided with a cooling hole communicating with the cooling channel.

[0032] Optionally, a plurality of the first through holes are provided, a plurality of the cooling holes are provided, and the first through holes correspond to the cooling holes one by one; and / or

[0033] A plurality of cooling holes are provided, and the plurality of cooling holes are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall.

[0034] Optionally, the main combustion stage annular wall is provided with a plurality of air holes located between the main combustion stage blades and the end surface of the discharge end in the length direction of the pre-combustion stage annular wall, and the air holes are used to introduce the air into the main combustion stage annular channel.

[0035] Optionally, the free end of the center rod is spaced apart from the end face of the discharge end in the length direction of the pre-combustion stage annular wall, the center rod has a blowing channel for letting air in, the free end of the center rod is provided with a blowing hole connected to the blowing channel, the blowing direction of the blowing hole forms an angle with the length direction of the pre-combustion stage annular wall, and the angle is greater than or equal to 0 degrees and less than 90 degrees.

[0036] Optionally, the angle between the blowing direction of the blowing hole and the length direction of the pre-combustion stage annular wall is greater than or equal to 15 degrees and less than 45 degrees; and / or

[0037] The blow-off holes are provided in plurality, and the plurality of blow-off holes are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall; and / or

[0038] In a projection plane orthogonal to the length direction of the pre-combustion stage annular wall, the central rod is substantially located at the center of the pre-combustion stage channel.

[0039] Optionally, at least two main combustion stage annular walls are provided, and two adjacent main combustion stage annular walls are arranged at intervals to form the main combustion stage sub-annular channel;

[0040] The swirl blades include main combustion stage sub-blades arranged in the main combustion stage sub-annular channel, and a main swirl sub-channel is formed between the main combustion stage sub-blades and two adjacent main combustion stage annular walls. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of a multi-stage swirl nozzle according to a specific embodiment of the present invention.

[0042] Figure 2 It is a cross-sectional view of a multi-stage swirl nozzle according to a specific embodiment of the present invention.

[0043] Figure 3 yes Figure 2 AA view in.

[0044] Figure 4 yes Figure 2 BB view in.

[0045] Reference numerals:

[0046] 1000-multi-stage swirl nozzle, 100-pre-combustion stage annular wall, 110-pre-combustion stage channel, 111-minimum pre-combustion stage channel section, 112-straight section, 120-feed end, 130-discharge end, 140-first annular convergent protrusion, 150-annular expansion protrusion, 151-cooling hole, 200-center rod, 210-annular cavity, 220-free end, 230-blowing channel, 240-blowing hole, 300-main combustion stage annular wall, 3 10-main combustion stage annular channel, 320-second annular convergent protrusion, 330-air hole, 400-swirl blade, 410-pre-combustion stage blade, 411-pre-swirl flow channel, 420-main combustion stage blade, 421-main swirl flow channel, a-pre-liquid channel, a1-pre-liquid connecting port, b-pre-gas channel, b1-pre-gas connecting port, c-main liquid channel, c1-main liquid connecting port, d-main gas channel, d1-main gas connecting port, e-cooling channel. DETAILED DESCRIPTION

[0047] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0048] The following describes a dual-fuel lean premixed multi-stage swirl nozzle 1000 according to an embodiment of the present invention with reference to the accompanying drawings. Figures 1 to 4As shown, the dual-fuel lean premixed multi-stage swirl nozzle 1000 of the present invention comprises a pre-combustion stage annular wall 100, a center rod 200 and a main combustion stage annular wall 300. The pre-combustion stage annular wall 100 has a pre-combustion stage channel 110 penetrating in its length direction and a feed end 120 and a discharge end 130 arranged opposite to each other in its length direction. The center rod 200 is arranged in the pre-combustion stage channel 110 and extends from the feed end 120 toward the discharge end 130. The center rod 200 is arranged at intervals with the pre-combustion stage annular wall 100 to form an annular cavity 210. The main combustion stage annular wall 300 is arranged around the pre-combustion stage annular wall 100. The main combustion stage annular wall 300 is arranged at intervals with the pre-combustion stage annular wall 100 to form a main combustion stage annular channel 310. Among them, the center rod 200 and / or the pre-combustion stage annular wall 100 have a pre-liquid channel a connected to the pre-combustion stage channel 110 and spraying liquid fuel into the pre-combustion stage channel 110, the center rod 200 and / or the pre-combustion stage annular wall 100 have a pre-gas channel b connected to the pre-combustion stage channel 110 and spraying gas fuel into the pre-combustion stage channel 110, the pre-combustion stage annular wall 100 and / or the main combustion stage annular wall 300 have a main liquid channel c connected to the main combustion stage annular channel 310 and spraying liquid fuel into the main combustion stage annular channel 310, the pre-combustion stage annular wall 100 and / or the main combustion stage annular wall 200 have a main gas channel d connected to the main combustion stage annular channel 310 and spraying gas fuel into the main combustion stage annular channel 310.

[0049] According to the multi-stage swirl nozzle 1000 of the present invention, the multi-stage swirl nozzle 1000 can realize the real-time switching of gas fuel and liquid fuel by controlling the operation of the pre-liquid channel a, the pre-gas channel b, the main liquid channel c and the main gas channel d, and can also realize the separate operation of the gas fuel and the liquid fuel, and can also realize the mixed operation of the gas fuel and the liquid fuel. At the same time, the demand for gas fuel and liquid fuel can also be controlled according to the requirements of the working conditions, so as to meet the different requirements of the combustion chamber. That is, when the working conditions are low, only the pre-liquid channel a and the pre-gas channel b can be allowed to work, so as to ensure that the combustion chamber has a stable combustion state. As the working conditions improve, the pre-liquid channel a, the pre-gas channel b, the main liquid channel c and the main gas channel d can be allowed to work at the same time, which can meet the requirements of higher working conditions.

[0050] like Figures 1 to 4 In order to make the technical solution of the present application easier to understand, the technical solution of the present application is described in more detail below with a specific implementation of the multi-stage swirl nozzle 1000. It should be noted that the length direction of the pre-combustion stage annular wall 100 is the same as that of the pre-combustion stage annular wall 100. Figure 2 The left and right directions shown are consistent.

[0051] In some embodiments, the liquid fuel in the present invention is fuel oil, and the gas fuel in the present invention is natural gas. The swirl nozzle 1000 is one of the main parts of the turbine combustion chamber. The main function of the swirl nozzle 1000 is to mix the gas fuel, liquid fuel and air, and then spray the mixed gas into the combustion chamber to improve the combustion efficiency of the gas fuel and liquid fuel.

[0052] In some specific embodiments, Figures 1 to 4 As shown, the shape of the pre-combustion stage annular wall 100 is roughly a long column. Preferably, the pre-combustion stage annular wall 100 in the present invention is cylindrical. The pre-combustion stage annular wall 100 has a pre-combustion stage channel 110 running through its length direction, and the pre-combustion stage channel 110 can mix gas fuel, liquid fuel and air, thereby improving the combustion rate of gas fuel and liquid fuel. The pre-combustion stage channel 110 has a feed end 120 and a discharge end 130 arranged opposite to each other in the length direction.

[0053] In some specific embodiments, Figures 1 to 4 As shown, the center rod 200 is disposed in the pre-combustion stage channel 110 and extends from the feed end 120 toward the discharge end 130, and the center rod 200 is spaced apart from the pre-combustion stage annular wall 100 to form an annular cavity 210. In other words, the center rod 200 is located in the pre-combustion stage channel 110, and the center rod 200 extends from the feed end 120 toward the discharge end 130 to the middle of the pre-combustion stage channel 110. Among them, the center rod 200 is spaced apart from the inner wall surface of the pre-combustion stage annular wall 100 to form an annular cavity 210.

[0054] In some specific embodiments, Figures 1 to 4 As shown, the center rod 200 and / or the pre-combustion stage annular wall 100 has a pre-liquid channel a that is connected to the pre-combustion stage channel 110 and sprays liquid fuel into the pre-combustion stage channel 110, and the center rod 200 and / or the pre-combustion stage annular wall 100 has a pre-gas channel b that is connected to the pre-combustion stage channel 110 and sprays gas fuel into the pre-combustion stage channel 110. Specifically, the pre-liquid channel a and the pre-gas channel b can spray liquid fuel and gas fuel into the pre-combustion stage channel 110, and the liquid fuel, gas fuel and air are fully mixed in the pre-combustion stage channel 110 and then enter the combustion chamber, thereby improving the combustion efficiency of the liquid fuel and the gas fuel. Among them, the pre-liquid channel a can be located on the center rod 200, and can also be located on the pre-combustion stage annular wall 100. Further, the center rod 200 and the pre-combustion stage annular wall 100 both have a pre-liquid channel a. Similarly, the setting method of the pre-gas channel b is similar to the setting method of the pre-liquid channel a, which will not be repeated here.

[0055] Preferably, the pre-liquid channel a and the pre-gas channel b in the present invention are both located on the central rod 200 .

[0056] In some specific embodiments, Figures 1 to 4 As shown, the main combustion stage annular wall 300 is arranged around the pre-combustion stage annular wall 100, that is, the main combustion stage annular wall 300 is installed on the periphery of the pre-combustion stage annular wall 100. The main combustion stage annular wall 300 and the pre-combustion stage annular wall 100 are arranged at intervals to form a main combustion stage annular channel 310. The shape of the main combustion stage annular wall 300 is similar to that of the pre-combustion stage annular wall 100. It should be noted that when the operating condition is low, the combustion requirements of the combustion chamber can be met by spraying liquid fuel and gas fuel into the pre-combustion stage channel 110 through the pre-liquid channel a and the pre-gas channel b. At this time, the main combustion stage annular channel 310 is mainly used for circulating air, that is, continuously introducing air into the combustion chamber. As the working conditions continue to improve, the liquid fuel and gas fuel required by the combustion chamber continue to increase. When the demand for liquid fuel and gas fuel exceeds a certain value, a large amount of liquid fuel, a large amount of gas fuel and air will not be fully mixed in the pre-combustion stage channel 110, resulting in incomplete combustion of liquid fuel and gas fuel in the combustion chamber and low combustion efficiency, that is, not only a large amount of liquid fuel and gas fuel are wasted, but also the combustion efficiency of liquid fuel and gas fuel in the combustion chamber is reduced. In order to avoid the above situation, a part of the liquid fuel and gas fuel are preferably passed into the pre-combustion stage channel 110, and the remaining liquid fuel and gas fuel are passed into the main combustion stage annular channel 310, which can not only ensure the working efficiency of the pre-combustion stage channel 110, but also improve the combustion efficiency of liquid fuel and gas fuel through the main combustion stage annular channel 310. Therefore, the pre-combustion stage channel 110 and the main combustion stage annular channel 310 can adapt to the needs of different working conditions and ensure the combustion efficiency of liquid fuel and gas fuel.

[0057] In some specific embodiments, Figures 1 to 4 As shown, the pre-combustion stage annular wall 100 and / or the main combustion stage annular wall 300 has a main liquid channel c that is connected to the main combustion stage annular channel 310 and sprays liquid fuel into the main combustion stage annular channel 310, and the pre-combustion stage annular wall 100 and / or the main combustion stage annular wall 200 has a main gas channel d that is connected to the main combustion stage annular channel 310 and sprays gas fuel into the main combustion stage annular channel 310. Specifically, the main liquid channel c and the main gas channel d can spray liquid fuel and gas fuel into the main combustion stage annular channel 310, and the liquid fuel, gas fuel and air are fully mixed in the main combustion stage annular channel 310 and then enter the combustion chamber, thereby improving the combustion efficiency of the liquid fuel and gas fuel. Among them, the main liquid channel c can be located on the pre-combustion stage annular wall 100, and can also be located on the main combustion stage annular wall 300. Further, the main combustion stage annular wall 300 and the pre-combustion stage annular wall 100 both have the main liquid channel c. Similarly, the configuration of the main gas channel d is similar to that of the main liquid channel c, which will not be described in detail here.

[0058] Preferably, the main gas channel d and the main liquid channel c in the present invention are both located on the main combustion stage annular wall 300 .

[0059] In some specific embodiments, Figures 1 to 4 As shown, there are multiple pre-liquid connecting ports a1 between the pre-combustion stage channel 110 and the pre-liquid channel a, and the multiple pre-liquid connecting ports a1 are arranged at intervals along the circumference of the pre-combustion stage annular wall 100, so that the liquid fuel injected into the pre-combustion stage channel 110 can be more uniform, and at the same time, it can also ensure that the liquid fuel is mixed with the air in the pre-combustion stage channel 110 more fully and evenly.

[0060] In some specific embodiments, Figures 1 to 4 As shown, there are multiple pre-gas communication ports b1 between the pre-combustion stage channel 110 and the pre-liquid channel a, and the multiple pre-gas communication ports b1 are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall 100. The technical effect of the pre-gas communication port b1 is similar to that of the pre-liquid communication port a1, and will not be repeated here.

[0061] Optionally, the number of the pre-liquid communication ports a1 or the pre-gas communication ports b1 is 6-18.

[0062] Optionally, the aperture of the pre-liquid communication port a1 or the pre-gas communication port b1 is 1-5 mm.

[0063] Optionally, the central axis of the pre-liquid communication port a1 or the central axis of the pre-gas communication port b1 is orthogonal to the central axis of the pre-combustion stage channel 110 .

[0064] In some specific embodiments, Figures 1 to 4 As shown, the main combustion stage annular channel 310 and the main liquid channel c are provided with a plurality of main liquid communication ports c1, which are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall 100. The technical effect of the main liquid communication port c1 is similar to that of the pre-liquid communication port a1, and will not be repeated here.

[0065] In some specific embodiments, Figures 1 to 4 As shown, there are multiple main gas communication ports d1 between the main combustion stage annular channel 310 and the main gas channel d, and the multiple main gas communication ports d1 are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall 100. The technical effect of the main gas communication port d1 is similar to that of the pre-liquid communication port a1, which will not be repeated here.

[0066] Optionally, the number of the main liquid communication ports c1 or the main gas communication ports d1 is 20-40.

[0067] Optionally, the aperture of the main liquid communication port c1 or the main gas communication port d1 is 1-5 mm.

[0068] Optionally, the central axis of the main liquid communication port c1 or the central axis of the main gas communication port d1 is orthogonal to the central axis of the pre-combustion stage channel 110 .

[0069] In some specific embodiments, Figures 1 to 4 As shown, the multi-stage swirl nozzle 1000 further includes swirl blades 400, which include pre-combustion stage blades 410 disposed in the annular cavity 210 and main combustion stage blades 420 disposed in the main combustion stage annular channel 310, a pre-swirl flow channel 411 is formed between the pre-combustion stage blades 410, the pre-combustion stage annular wall 100 and the center rod 200, and a main swirl flow channel 421 is formed between the main combustion stage blades 420, the pre-combustion stage annular wall 100 and the main combustion stage annular wall 300. Specifically, air with a certain air pressure is guided by the pre-combustion stage blades 410 and the main combustion stage blades 420, so that the air forms swirl air in the pre-swirl flow channel 411 and the main swirl flow channel 421, and the swirl air can form a recirculation zone in the combustion chamber, thereby improving the stability of the flame in the combustion chamber.

[0070] In some specific embodiments, Figures 1 to 4 As shown, the pre-combustion stage blades 410 are located between the feed end 120 and the free end 220 of the center rod 200 in the length direction of the pre-combustion stage annular wall 100 .

[0071] In some specific embodiments, Figures 1 to 4 As shown, the pre-liquid channel a and / or the pre-gas channel b are connected to the pre-swirl flow channel 411. Specifically, when the liquid fuel and the gas fuel are introduced into the pre-swirl flow channel 411, the liquid fuel and the gas fuel can swirl along with the swirling air, so that the liquid fuel, the gas fuel and the air can be mixed more fully and more evenly, thereby improving the combustion efficiency of the liquid fuel and the gas fuel.

[0072] In some specific embodiments, Figures 1 to 4 As shown, a plurality of pre-combustion stage blades 410 are provided, and the plurality of pre-combustion stage blades 410 are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall 100 .

[0073] Optionally, the pre-combustion stage blades 410 are straight blades.

[0074] Optionally, the blade angle of the pre-combustion stage blade 410 is 30°-50°.

[0075] Optionally, the number of pre-combustion stage blades 410 is 6-18.

[0076] Optionally, the number of the pre-combustion stage blades 410 is the same as the number of the pre-liquid communication ports a1 and the pre-gas communication ports b1.

[0077] In some specific embodiments, Figures 1 to 4 As shown, the main combustion stage blades 420 are located between the feed end 120 and the free end 220 of the center rod 200 in the length direction of the pre-combustion stage annular wall 100 .

[0078] In some specific embodiments, Figures 1 to 4 As shown, the main liquid channel c and / or the main gas channel d are connected to the main swirl flow channel 421. Specifically, when the liquid fuel and the gas fuel are introduced into the main swirl flow channel 421, the liquid fuel and the gas fuel can swirl along with the swirling air, so that the liquid fuel, the gas fuel and the air can be mixed more fully and more evenly, thereby improving the combustion efficiency of the liquid fuel and the gas fuel.

[0079] In some specific embodiments, Figures 1 to 4 As shown, a plurality of main combustion stage blades 420 are provided, and the plurality of main combustion stage blades 420 are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall 100 .

[0080] Optionally, the main combustion stage blades 420 are straight blades.

[0081] Optionally, the blade angle of the main combustion stage blade 420 is 30°-40°.

[0082] Optionally, the number of main combustion stage blades 420 is 10-20.

[0083] Optionally, the number of the main liquid communication ports c1 and the number of the main gas communication ports d1 are both twice the number of the main combustion stage blades 420 .

[0084] In some specific embodiments, Figures 1 to 4 As shown, a first annular convergent protrusion 140 is provided on the inner wall surface of the pre-combustion stage annular wall 100, which is located between the pre-combustion stage blade 411 and the free end 220 of the center rod 200 in the length direction of the pre-combustion stage annular wall 100, and the protrusion distance of the first annular convergent protrusion 140 gradually increases in the direction from the feed end 120 to the discharge end 130. It should be noted that the protrusion distance of the first annular convergent protrusion 140 can be understood as the height of the protrusion. The larger the protrusion distance of the first annular convergent protrusion 140, the smaller the radial cross-section of the pre-combustion stage channel 110, that is, the radial cross-section of the pre-combustion stage channel 110 gradually decreases in the direction from the feed end 120 to the discharge end 130. The first annular convergent protrusion 140 can converge the swirl gas flowing out of the pre-swirl flow channel 411, thereby accelerating the swirl gas, making the swirl speed of the swirl gas faster, and thus making the mixed gas more fully mixed. At the same time, the swirl gas continuously converges to the central axis position of the pre-combustion stage channel 110 , thereby increasing the gas pressure at the central axis position of the pre-combustion stage channel 110 , which can effectively suppress the flashback in the multi-stage swirl nozzle 1000 .

[0085] In some specific embodiments, Figure 2 As shown, the inner surface of the first annular convergent protrusion 140 is a conical surface, which is more conducive to guiding the swirling gas.

[0086] Optionally, the inner surface of the first annular convergent protrusion 140 is a conical surface, and the generatrix of the conical surface forms an angle between 30 degrees and 50 degrees with the central axis of the pre-combustion stage channel 110 .

[0087] In some specific embodiments, Figure 2 As shown, the position of the first annular convergent protrusion 140 with the maximum protrusion distance is set to the minimum pre-combustion stage channel cross section 111, and the end surface of the free end 220 of the center rod 200 is flush with the minimum pre-combustion stage channel cross section 111 in the length direction of the pre-combustion stage annular wall 100.

[0088] In some specific embodiments, Figure 2 As shown, the pre-combustion stage passage 110 has a straight section 112, and the straight section 112 is located between the pre-combustion stage blades 411 and the first annular convergent protrusion 140 in the length direction of the pre-combustion stage annular wall 100. The swirling gas flowing out through the pre-swirling flow channel 411 can be fully mixed in the straight section 112. Specifically, the air enters the pre-combustion stage passage 110 to form a strong swirling motion, which is fully developed in the straight section 112 and then accelerated through the first annular convergent protrusion 140, so that flashback can be suppressed.

[0089] In some specific embodiments, Figures 1 to 4 As shown, the inner wall surface of the main combustion stage annular wall 300 and / or the outer wall surface of the pre-combustion stage annular wall 100 are provided with a second annular convergent protrusion 320 located between the main combustion stage blade 420 and the end surface of the discharge end 130 in the length direction of the pre-combustion stage annular wall 100, and the protrusion distance of the second annular convergent protrusion 320 gradually increases in the direction from the feed end to the discharge end. The function and principle of the second annular convergent protrusion 320 are the same as those of the first annular convergent protrusion 140, and will not be repeated here.

[0090] In some specific embodiments, Figure 2 As shown, the inner surface of the second annular convergent protrusion 320 is a conical surface, which is more conducive to guiding the swirling gas.

[0091] Optionally, the inner surface of the second annular convergent protrusion 320 is a conical surface, and the generatrix of the conical surface forms an angle between 15 degrees and 45 degrees with the central axis of the pre-combustion stage channel 110 .

[0092] Optionally, the second annular convergent protrusion 320 is located on the outer wall surface of the pre-combustion stage annular wall 100 .

[0093] Specifically, the air enters the main swirl flow channel 421 to form a weak swirl motion, and then flows faster through the second annular convergent protrusion 320, thereby suppressing backfire.

[0094] In some specific embodiments, Figure 2As shown, an annular expansion protrusion 150 is provided on the inner wall surface of the pre-combustion stage annular wall 100, which is located between the free end 220 of the center rod 200 and the end surface of the discharge end 130 in the length direction of the pre-combustion stage annular wall 100. The protrusion distance of the annular expansion protrusion 150 gradually decreases in the direction from the feed end to the discharge end, and the annular expansion protrusion 150 is connected to the first annular convergent protrusion 140. Specifically, the smaller the protrusion distance of the annular expansion protrusion 150, the larger the radial cross-section of the pre-combustion stage channel 110, that is, the radial cross-section of the pre-combustion stage channel 110 gradually increases in the direction from the feed end 120 to the discharge end 130. The annular expansion protrusion 150 can reduce the speed of the swirling gas passing through the first annular convergent protrusion 140, thereby prompting the swirling gas located at the annular expansion protrusion 150 to form a central recirculation zone, which is beneficial to improving the flame stabilization ability of the combustion chamber.

[0095] In some specific embodiments, Figure 2 As shown, the inner surface of the annular expansion protrusion 150 is a conical surface, which is more conducive to guiding the swirling gas.

[0096] Optionally, the inner surface of the annular expansion protrusion 150 is a conical surface, and the generatrix of the conical surface is between 30 degrees and 50 degrees with the central axis of the pre-combustion stage channel 110 .

[0097] In the present invention, both the pre-combustion channel 110 and the main combustion annular channel 310 adopt a premixed combustion organization mode to reduce the pollutant emission level. After the liquid fuel and gas fuel in the pre-combustion channel 110 enter the pre-swirl flow channel 411, they are further fully mixed with the air in the straight section 112 and the first annular convergent protrusion 140, and then the uniform mixed gas enters the combustion chamber through the annular expansion protrusion 150 for combustion.

[0098] The liquid fuel and gas fuel in the main swirl flow channel 421 enter the straight section and the second annular convergent protrusion 320 and are further fully mixed with the air to form a uniform premixed gas. The combustion equivalence ratio of the main combustion stage is 0.5-0.7. At the same time, since the main combustion stage swirl is a weak swirl, the main combustion stage premixed gas burns outside the central recirculation zone. The design goal of low emissions for the main combustion stage is achieved through lean premixing and shortening the gas residence time.

[0099] In summary, the pre-combustion channel 110 adopts a convergent-divergent structure, the first annular convergent protrusion 140 increases the flow rate of the mixed gas, which is conducive to suppressing the flashback and spontaneous combustion of the pre-combustion channel 110, and the annular expansion protrusion 150 of the pre-combustion channel 110 reduces the flow rate of the mixed gas, prompting the formation of a central recirculation zone, which is conducive to improving the flame stabilization ability. The main swirl flow channel 421 also adopts a convergent structure, and the second annular convergent protrusion 320 increases the flow rate of the mixed gas, which is conducive to suppressing the flashback and spontaneous combustion of the main combustion stage.

[0100] In some specific embodiments, the first annular convergent protrusion 140 is provided with a first through hole extending in the length direction of the pre-combustion stage annular wall 100, and the annular expansion protrusion 150 is provided with a cooling hole 151 connected to the first through hole. Specifically, the mixed gas located at the first annular convergent protrusion 140 can enter the position of the annular expansion protrusion 150 through the first through hole and the cooling hole 151, so that the annular expansion protrusion 150 can be cooled, effectively preventing the temperature of the annular expansion protrusion 150 from being too high.

[0101] In some specific embodiments, Figure 2 As shown, the pre-combustion stage annular wall 100 has a cooling channel e for introducing air, and the annular expansion protrusion 150 is provided with a cooling hole 151 connected to the cooling channel e. Specifically, the mixed gas can enter the position of the annular expansion protrusion 150 through the cooling channel e and the cooling hole 151, so that the annular expansion protrusion 150 can be cooled, effectively preventing the temperature of the annular expansion protrusion 150 from being too high.

[0102] Optionally, the diameter of the cooling hole 151 is 1-3 mm.

[0103] Optionally, the central axis of the cooling hole 151 is parallel to the central axis of the pre-combustion stage channel 110 .

[0104] In some specific embodiments, Figure 2 As shown, a plurality of first through holes are provided, a plurality of cooling holes 151 are provided, and the first through holes correspond to the cooling holes 151 one by one.

[0105] In some specific embodiments, Figure 2 As shown, a plurality of cooling holes 151 are provided, and the plurality of cooling holes 151 are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall 100 .

[0106] In some specific embodiments, Figure 1 and Figure 2 As shown, the main combustion stage annular wall 300 is provided with a plurality of air holes 330 located between the main combustion stage blades 420 and the end face of the discharge end 130 in the length direction of the pre-combustion stage annular wall 100. The air holes 330 are used to introduce air into the main combustion stage annular channel 310 to prevent boundary layer flashback on the main combustion stage annular wall 300.

[0107] Optionally, the diameter of the air hole 330 is 1-3 mm.

[0108] Optionally, the central axis of the air hole 330 is perpendicular to the central axis of the pre-combustion stage channel 110 .

[0109] Optionally, a plurality of air holes 330 are provided, and the plurality of air holes 330 are arranged at intervals along the circumferential direction of the pre-combustion stage passage 110 .

[0110] In some specific embodiments, Figure 2 As shown, the free end 220 of the center rod 200 is spaced apart from the end surface of the discharge end 130 in the length direction of the pre-combustion stage annular wall 100, the center rod 200 has a blow-off channel 230 for introducing air, and the free end 220 of the center rod 200 is provided with a blow-off hole 240 connected to the blow-off channel 230. Specifically, air with a certain pressure enters the pre-combustion stage channel 110 through the blow-off channel 230 and the blow-off hole 240, thereby increasing the air pressure at the center of the pre-combustion stage channel 110, and effectively suppressing the flashback in the multi-stage swirl nozzle 1000. That is to say, in the pre-combustion channel 110, the mixed gas continuously gathers toward the inner wall surface of the pre-combustion annular wall 100 under the swirl condition, so that the air pressure at the inner wall surface of the pre-combustion annular wall 100 continuously increases, and the air pressure at the center of the pre-combustion channel 110 continuously decreases, and then the axial speed of the mixed gas at the center of the pre-combustion channel 110 decreases, which makes it easy to generate flashback at the position of the discharge end 130. At the same time, when the ignition is unsuccessful or the flameout occurs, there will be some pre-mixed gas in the combustion chamber, and the center rod 200 continuously introduces air through the blow-off hole 240, which can blow the unburned mixed gas out of the combustion chamber to avoid the explosion phenomenon when the ignition is ignited in the combustion chamber next time.

[0111] In some specific embodiments, Figure 2 As shown, the blowing direction of the blowing hole 240 forms an angle with the length direction of the pre-combustion stage annular wall 100 , the angle being greater than or equal to 0 degrees and less than 90 degrees. Specifically, the air flowing from the blowing hole 240 into the pre-combustion stage channel 110 generally flows toward the discharge end 130 .

[0112] Alternatively, if Figure 2 As shown, the angle between the blowing direction of the blowing hole 240 and the length direction of the pre-combustion stage annular wall 100 is greater than or equal to 15 degrees and less than 45 degrees.

[0113] In some specific embodiments, Figure 2 As shown, in the projection plane perpendicular to the length direction of the pre-combustion stage annular wall 100 , the center rod 200 is substantially located at the center position of the pre-combustion stage channel 110 . In other words, the center rod 200 is located at the center line position of the pre-combustion stage channel 110 .

[0114] It should be noted that the projection surface orthogonal to the length direction of the pre-combustion stage annular wall 100 can be understood as a radial cross section of the pre-combustion stage annular wall 100 .

[0115] In some specific embodiments, Figure 2As shown, a plurality of blow-off holes 240 are provided, and the plurality of blow-off holes 240 are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall 100. Specifically, the blow-off holes 240 can evenly blow air into the pre-combustion stage channel 110, thereby making the air pressure in the pre-combustion stage channel 110 more uniform, that is, making the air pressure in the pre-combustion stage channel 110 more stable.

[0116] Optionally, the number of the blow-off holes 240 is 4-12.

[0117] Optionally, the diameter of the blow-off hole 240 is 2-6 mm.

[0118] In some specific embodiments, at least two main combustion stage annular walls 300 are provided, and two adjacent main combustion stage annular walls 300 are arranged at intervals to form a main combustion stage sub-annular channel. The swirl blade 400 includes a main combustion stage sub-blade arranged in the main combustion stage sub-annular channel, and a main swirl sub-channel is formed between the main combustion stage sub-blade and the two adjacent main combustion stage annular walls.

[0119] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0120] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0121] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0122] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0123] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0124] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A dual-fuel lean premixed multi-stage swirl nozzle, characterized in that: include: A pre-combustion stage annular wall, wherein the pre-combustion stage annular wall has a pre-combustion stage channel penetrating in the length direction thereof and a feed end and a discharge end arranged opposite to each other in the length direction thereof; A center rod, the center rod is disposed in the pre-combustion stage channel and extends from the feed end toward the discharge end, the center rod and the pre-combustion stage annular wall are spaced apart to form an annular cavity; a main combustion stage annular wall, the main combustion stage annular wall being arranged around the pre-combustion stage annular wall, the main combustion stage annular wall being spaced apart from the pre-combustion stage annular wall to form a main combustion stage annular channel; Wherein, the central rod and / or the pre-combustion stage annular wall has a pre-liquid channel which is connected with the pre-combustion stage channel and sprays liquid fuel into the pre-combustion stage channel; The central rod and / or the pre-combustion stage annular wall has a pre-gas passage that is in communication with the pre-combustion stage passage and injects gas fuel into the pre-combustion stage passage; The pre-combustion stage annular wall and / or the main combustion stage annular wall has a main liquid channel which is in communication with the main combustion stage annular channel and injects the liquid fuel into the main combustion stage annular channel; The pre-combustion stage annular wall and / or the main combustion stage annular wall have a main gas passage which is communicated with the main combustion stage annular passage and injects the gas fuel into the main combustion stage annular passage.

2. The dual-fuel lean premixed multi-stage swirl nozzle according to claim 1, characterized in that: A plurality of pre-liquid communication ports are provided between the pre-combustion stage channel and the pre-liquid channel, and the plurality of pre-liquid communication ports are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall; and / or A plurality of pre-gas communication openings are provided between the pre-combustion stage channel and the pre-liquid channel, and the plurality of pre-gas communication openings are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall; and / or The main combustion stage annular channel and the main liquid channel are provided with a plurality of main liquid communication ports, and the plurality of main liquid communication ports are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall; and / or A plurality of main gas communication ports are provided between the main combustion stage annular channel and the main gas channel, and the plurality of main gas communication ports are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall.

3. The dual-fuel lean premixed multi-stage swirl nozzle according to claim 1, characterized in that: Also includes: The swirl blades include pre-combustion stage blades arranged in the annular cavity and main combustion stage blades arranged in the main combustion stage annular channel, a pre-swirl flow channel is formed between the pre-combustion stage blades, the pre-combustion stage annular wall and the center rod, and a main swirl flow channel is formed between the main combustion stage blades, the pre-combustion stage annular wall and the main combustion stage annular wall.

4. The dual-fuel lean premixed multi-stage swirl nozzle according to claim 3, characterized in that: The pre-combustion stage blades are located between the feed end and the free end of the central rod in the length direction of the pre-combustion stage annular wall; and / or The main combustion stage blades are located between the feed end and the free end of the central rod in the length direction of the pre-combustion stage annular wall; and / or The pre-combustion stage blades and / or the main combustion stage blades are provided in plurality, and the plurality of pre-combustion stage blades and / or the plurality of main combustion stage blades are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall; and / or The pre-liquid channel and / or the pre-gas channel are in communication with the pre-swirl flow channel; and / or The main liquid channel and / or the main gas channel are communicated with the main swirl flow channel.

5. The dual-fuel lean premixed multi-stage swirl nozzle according to claim 3, characterized in that: A first annular convergent protrusion is provided on the inner wall surface of the pre-combustion stage annular wall and is located between the pre-combustion stage blades and the free end of the center rod in the length direction of the pre-combustion stage annular wall, and a protrusion distance of the first annular convergent protrusion gradually increases in the direction from the feed end to the discharge end, and the larger the protrusion distance of the first annular convergent protrusion, the smaller the radial cross-section of the pre-combustion stage channel; and / or A second annular convergent protrusion is provided on the inner wall surface of the main combustion stage annular wall and / or the outer wall surface of the pre-combustion stage annular wall, which is located between the main combustion stage blades and the end face of the discharge end in the length direction of the pre-combustion stage annular wall. The protrusion distance of the second annular convergence protrusion gradually increases in the direction from the feed end to the discharge end. The larger the protrusion distance of the second annular convergence protrusion, the larger the radial cross-section of the pre-combustion stage channel.

6. The dual-fuel lean premixed multi-stage swirl nozzle according to claim 5, characterized in that: The position of the first annular convergent protrusion with the maximum protrusion distance is set to the minimum pre-combustion stage channel cross section, and the end surface of the free end of the central rod is flush with the minimum pre-combustion stage channel cross section in the length direction of the pre-combustion stage annular wall.

7. The dual-fuel lean premixed multi-stage swirl nozzle according to claim 5, characterized in that: An annular expansion protrusion is provided on the inner wall surface of the pre-combustion stage annular wall, which is located between the free end of the center rod and the end face of the discharge end in the length direction of the pre-combustion stage annular wall. The protrusion distance of the annular expansion protrusion gradually decreases in the direction from the feed end to the discharge end. The smaller the protrusion distance of the annular expansion protrusion, the larger the radial cross-section of the pre-combustion stage channel. The annular expansion protrusion is connected to the first annular convergence protrusion.

8. The dual-fuel lean premixed multi-stage swirl nozzle according to claim 7, characterized in that: The first annular convergent protrusion is provided with a first through hole extending in the length direction of the pre-combustion stage annular wall; The annular expansion protrusion is provided with a cooling hole communicating with the first through hole; and / or The pre-combustion stage annular wall has a cooling channel for introducing air, and the annular expansion protrusion is provided with a cooling hole communicating with the cooling channel.

9. The dual-fuel lean premixed multi-stage swirl nozzle according to claim 8, characterized in that: There are a plurality of first through holes, there are a plurality of cooling holes, and the first through holes correspond to the cooling holes one by one; and / or A plurality of cooling holes are provided, and the plurality of cooling holes are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall.

10. The dual-fuel lean premixed multi-stage swirl nozzle according to any one of claims 1 to 9, characterized in that: The main combustion stage annular wall is provided with a plurality of air holes located between the main combustion stage blades and the end surface of the discharge end in the length direction of the pre-combustion stage annular wall, and the air holes are used to introduce the air into the main combustion stage annular channel.

11. The dual-fuel lean premixed multi-stage swirl nozzle according to any one of claims 1 to 9, characterized in that: The free end of the center rod is spaced apart from the end face of the discharge end in the length direction of the pre-combustion stage annular wall, the center rod has a blowing channel for introducing air, the free end of the center rod is provided with a blowing hole connected to the blowing channel, the blowing direction of the blowing hole forms an angle with the length direction of the pre-combustion stage annular wall, and the angle is greater than or equal to 0 degrees and less than 90 degrees.

12. The dual-fuel lean premixed multi-stage swirl nozzle according to claim 11, characterized in that: The angle between the blowing direction of the blowing hole and the length direction of the pre-combustion stage annular wall is greater than or equal to 15 degrees and less than 45 degrees; and / or The blow-off holes are provided in plurality, and the plurality of blow-off holes are arranged at intervals along the circumferential direction of the pre-combustion stage annular wall; and / or In a projection plane orthogonal to the length direction of the pre-combustion stage annular wall, the central rod is substantially located at the center of the pre-combustion stage channel.

13. The dual-fuel lean premixed multi-stage swirl nozzle according to any one of claims 1 to 9, characterized in that: There are at least two main combustion stage annular walls, and two adjacent main combustion stage annular walls are arranged at intervals to form the main combustion stage sub-annular channel; The swirl blades include main combustion stage sub-blades arranged in the main combustion stage sub-annular channel, and a main swirl sub-channel is formed between the main combustion stage sub-blades and two adjacent main combustion stage annular walls.

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