CN116878026B

CN116878026B - Combustor subassembly and burner

Info

Publication number: CN116878026B
Application number: CN202310918538.XA
Authority: CN
Inventors: 李耀强; 钟猷兰; 张洪; 胡桃桃; 孙炎光; 顾明恒; 李亚聪
Original assignee: Enn Energy Power Technology Shanghai Co ltd
Current assignee: Enn Energy Power Technology Shanghai Co ltd
Priority date: 2023-07-25
Filing date: 2023-07-25
Publication date: 2025-07-22
Anticipated expiration: 2043-07-25
Also published as: CN116878026A

Abstract

The present invention relates to the technical field of power equipment, and discloses a burner assembly and a combustion device, wherein the burner assembly comprises: a first swirler and a first fuel pipe, wherein the first swirler has a first air channel, and the first fuel pipe is located in the first air channel; the surface of the first fuel pipe is provided with turbulent patterns and a plurality of first fuel holes, and the first fuel pipe sprays fuel into the first air channel through the first fuel holes. In the above-mentioned burner assembly, when air enters the first swirler through the first air channel, it will pass through the first fuel pipe. Since the surface of the first fuel pipe is provided with turbulent patterns, the air acts on the turbulent patterns when passing around the first fuel pipe, generating obvious turbulence, fully increasing the turbulence of the air, and quickly mixing with the fuel sprayed from the first fuel hole, thereby increasing the mixing uniformity of the fuel and the air, facilitating full combustion, and significantly reducing NOx emissions.

Description

Combustor subassembly and burner

Technical Field

The invention relates to the technical field of power equipment, in particular to a combustor assembly and a combustion device.

Background

Combustion polluting emissions pose an increasing hazard to human health and the environment, and legal regulations and related policies concerning controlling polluting emissions are becoming increasingly stringent. A certain requirement is also put on the problem of NOx pollution emission of micro gas turbines. Technical research on low NOx emissions by various gas turbine manufacturers has tended to mature, and common mainstream products can reach NOx emissions below 15ppm and even below 10 ppm. In order to realize low emission of combustion, the combustion equipment is required to be finely designed and modified, so that the NOx emission is reduced to the greatest extent while the combustion stability is ensured.

The combustion products of the micro gas turbine under high temperature flame contain NOx (nitrogen oxides), which mainly contains NO and NO2. Technical measures are taken to reduce the NOx emissions of micro gas turbines as much as possible. In a gas turbine, NOx is mainly thermal NOx generated by high combustion temperature, so that the emission amount of the gas turbine NOx is reduced, and it is critical to control the temperature in the combustion chamber at a low level (typically 1700K-1900K, which affects the combustion efficiency if the temperature is lower) and to make the temperature distribution in the combustion chamber uniform. This requires a very uniform fuel distribution in the combustion zone, minimizing the occurrence of localized high concentration spots of high concentration fuel. The existing low NOx emission burner of the ground gas turbine mainly comprises fuel classification, lean combustion premixing, steam humidification and the like. The ground gas turbine is commonly used in a dry low-emission technology, fuel is graded, so that fuel gas is uniformly distributed in a premixing section of the burner as far as possible, and after the mixture of the fuel gas and air is sprayed out of the burner, the temperature in a combustion area is generally lower than 2000K, so that the emission of thermal nitrogen oxides is reduced.

The prior middle-size and heavy-duty fuel gas combustion chamber usually adopts the configuration of a main combustion burner with a radial swirler structure and an axial swirler diffusion duty burner, a small part of fuel is subjected to diffusion combustion through the duty burner to realize stable combustion, and a large part of fuel is premixed through the main combustion burner, so that the structure is required to be optimized if NOx emission is required to be further reduced, and the two-stage swirler is modified.

Therefore, how to further reduce the emission of NOx is a problem to be solved.

Disclosure of Invention

The invention discloses a burner assembly and a burner device, which are used for further reducing NOx emission.

In a first aspect, a combustor assembly is provided, the combustor assembly comprising a first swirler and a first fuel pipe, wherein the first swirler is provided with a first air passage, the first fuel pipe is positioned in the first air passage, turbulence lines and a plurality of first fuel holes are distributed on the surface of the first fuel pipe, and the first fuel pipe injects fuel into the first air passage through the first fuel holes.

In the above-mentioned combustor subassembly, can pass through first fuel pipe after the air enters into first swirler through first air passage, because first fuel pipe surface is equipped with the vortex line, the air acts on the vortex line when around first fuel pipe, produces obvious turbulent flow, fully increases the turbulence degree of air to fully mix with the fuel that first fuel hole sprays rapidly, increase the misce bene of fuel and air, be favorable to fully burning, show reduction NOx emission.

Optionally, the first fuel pipe penetrates through two opposite side walls of the first air channel, threads are distributed on the circumferential surface of the first fuel pipe, the portions, located between the two side walls, of the threads of the first fuel pipe form turbulence lines, and at least one end of the first fuel pipe is connected with a limiting fixing piece through the threads.

Optionally, the air filter further comprises a second cyclone, wherein the second cyclone is provided with a second air channel, the first air channel surrounds the second air channel, an air inlet of the second air channel faces away from the second air channel, an air outlet of the second air channel surrounds an air outlet of the first air channel, and the first fuel pipe extends along the axial direction.

Optionally, the device further comprises an annular fuel chamber surrounding the second air channel and fixed with the outer wall of the second air channel, and a fuel supply pipe communicated with the annular fuel chamber, wherein one end of the first fuel pipe is fixedly connected with the annular fuel chamber, and the other end of the first fuel pipe is connected with the limiting fixing piece through the threads so as to clamp and fix the two opposite side walls of the second air channel.

Optionally, the number of the first fuel pipes is plural, and the plural first fuel pipes are spaced around the second air passage.

Optionally, the number of the first cyclones is multiple, the first cyclones are arranged in a stacked manner along the axial direction, and each first fuel pipe sequentially penetrates through a plurality of first air channels.

Optionally, each two adjacent first air passages share one of the side walls.

Optionally, the device further comprises a second fuel pipe and a head igniter, wherein the second fuel pipe is positioned in the second air channel, a plurality of second fuel holes are distributed on the circumferential surface of the second fuel pipe, a vane assembly is arranged in the second air channel, the second fuel holes are positioned at the upstream of the vane assembly, and the ignition end of the head igniter is positioned at the second fuel holes.

Optionally, the first fuel hole is formed with a counter bore at a surface opening of the first fuel tube, and an inner diameter of the counter bore is larger than an inner diameter of the first fuel hole.

In a second aspect, a combustion apparatus is provided, where the combustion apparatus includes a casing assembly, a flame tube assembly, and a burner assembly according to any of the foregoing embodiments, the flame tube assembly is located in the casing assembly, and an opening of the flame tube assembly is abutted to an air outlet of the first air channel.

Compared with the prior art, the burner has the same advantages as the burner assembly, and the details are omitted.

Drawings

FIG. 1 is a cross-sectional view of a combustion apparatus provided in an embodiment of the present application;

FIG. 2 is a cross-sectional view of the burner assembly of FIG. 1;

FIG. 3 is a cross-sectional view of the first cyclone of FIG. 2 taken perpendicular to its axis;

FIG. 4 is a perspective view of the burner assembly of FIG. 1;

FIG. 5 is a cross-sectional view of a variation of the burner assembly shown in FIG. 4;

FIG. 6 is a perspective view of the burner assembly of FIG. 5.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In connection with fig. 1 to 6:

The burner assembly 1 provided by the embodiment of the application comprises a first swirler 18 and a first fuel pipe 13, wherein the first swirler 18 is provided with a first air channel T1, the first fuel pipe 13 is positioned in the first air channel T1, turbulence lines and a plurality of first fuel holes 131 are distributed on the surface of the first fuel pipe 13, and the first fuel pipe 13 injects fuel into the first air channel T1 through the first fuel holes 131. The first swirler 18 and the first fuel pipe 13 serve as core components of the first burner.

In the above-mentioned burner assembly 1, when air enters the first swirler 18 through the first air channel T1 and then passes through the first fuel pipe 13, since the turbulent flow lines are provided on the surface of the first fuel pipe 13, the air acts on the turbulent flow lines when surrounding the first fuel pipe 13, so as to generate obvious turbulent flow, fully increase the turbulence of the air, and quickly fully mix with the fuel injected from the first fuel holes 131, thereby increasing the mixing uniformity of the fuel and the air, being beneficial to full combustion and remarkably reducing NOx emission.

In a specific embodiment, the first fuel pipe 13 penetrates two opposite side walls of the first air channel T1, the two side walls may be specifically an inner wall 183 and an outer wall 181, threads 132 are distributed on the circumferential surface of the first fuel pipe 13, the portion of the threads 132 of the first fuel pipe 13 located between the two side walls (such as the inner wall 183 and the outer wall 181) forms the turbulence lines, at least one end of the first fuel pipe 13 is connected with a limiting fixing member 15 through the threads 132, the limiting fixing member 15 may be configured at only one end of the first fuel pipe 13, or the limiting fixing member 15 may be configured at both ends, the limiting fixing member 15 may be specifically a nut, and the side wall inner wall 183 or the outer wall 181 is limited by using the limiting fixing member 15. The standard threads may be formed on the circumferential surface of the first fuel pipe 13 as the threads 132, and may be used as a threaded connection structure of the limiting fixing member 15, or may be formed as the turbulence lines, so as to increase the turbulence of air. Equivalent to the use of one-shot standard threads to perform both functions.

In a specific embodiment, the burner assembly 1 further comprises a second swirler 16, the second swirler 16 may be an axial swirler and as a duty second swirler 16 has a second air passage T2, and the air outlet of the second air passage T2 may be along the axial direction L, in particular, the second swirler 16 comprises a second swirl vane 163, an inlet passage enclosure wall 162 located upstream and an outlet section enclosure wall 161 located downstream, wherein the inlet passage enclosure wall 162 and the outlet section enclosure wall 161 enclose the second air passage T2, the second swirl assembly 163 is located in the second air passage T2, in particular, may be located at the junction of the inlet passage enclosure wall 162 and the outlet section enclosure wall 161, for swirling air or a mixed gas passing through the second air passage T2, and the air passes through the second swirl assembly 163 to create a swirling low velocity zone, thereby firmly anchoring the duty flame at the air outlet of the second air passage T2. The first swirler 18 may be a radial swirler, the first air passage T1 surrounding the second air passage T2, and the air outlet of the second air passage T2 surrounding the air outlet of the first air passage T1 and facing in the axial direction L. The inlet and outlet directions of the inner wall 183 may be substantially 90 degree angles, the angles may be rounded, the outer wall 181 may have a shape similar to the inner wall 183, the outer wall 181 and the inner wall 183 may be arranged along the axial direction L with a first air passage T1 annularly distributed therebetween, the inlet direction of the first air passage T1 may deviate from the second air passage T2 in the radial direction R, air may enter the first air passage T1 through the inlet, be mixed with fuel ejected from the first fuel pipe 13 in the first air passage T1, and be ejected substantially along the axial direction L when being ejected from the first air passage T1 after being swirled by the first swirling assembly 183 in the first air passage T1. It will be appreciated that the outer wall 181 may employ a converging streamline wall to increase the velocity of the air flow in the first air passage T1 and reduce the residence time to address flame flashback conditions that may occur due to the presence of hydrogen, providing the burner assembly with the ability to burn low proportions of hydrogen-containing fuel, and that the outer wall 181 may employ a diverging streamline wall. The first fuel pipe 13 extends in the axial direction L so as to penetrate through the inner wall 183 and the outer wall 181 distributed in the axial direction L. The outer wall 181, the first cyclone assembly 182, and the inner wall 183 may be sequentially welded. The first swirl vanes in the first swirl assembly 183 and the second swirl vanes in the second swirl assembly 163 may each be airfoil vanes or curved vanes.

In a specific embodiment, the burner assembly 1 further comprises an annular fuel chamber 19 surrounding the second air passage T2 and fixed to an outer wall of the second air passage T2 (e.g. an inlet passage enclosure wall 162), and a fuel supply pipe 12 communicating with the annular fuel chamber 19, the fuel supply pipe 12 extending in the axial direction L supplying fuel into the annular fuel chamber 19, the supply pipe 12 being in particular connected to a rear wall 191 of the annular fuel chamber 19, the fuel being in particular gas, the gas fuel being dispersed in the annular fuel chamber 19, one end of the first fuel pipe 13 being fixedly connected and communicating with the annular fuel chamber 19, and the other end being connected to the stopper fixing member 15 by a screw thread 132 for clamping and fixing the opposite two side walls of the second air passage T2. The annular fuel chamber 19 simultaneously serves to fix the first fuel pipe 13 and supply fuel to the first fuel pipe 13.

In a specific embodiment, the number of the first fuel pipes 13 is plural (e.g., 12 to 24), and the plural first fuel pipes 13 are spaced around the second air passage T2 to fix different positions of the inner wall 183 and the outer wall 181 in the circumferential direction while supplying fuel into the first air passage T1 at different angles in the circumferential direction. Furthermore, each of the first fuel pipes 13 is fixed to and communicates with the annular fuel chamber 19, and the annular distribution of the annular fuel chamber 19 serves to fix and supply fuel to the first fuel pipes 13 different in the annular direction.

The main fuel enters the annular fuel chamber 19 from the fuel supply pipe 12 of the main fuel, is distributed from the annular fuel chamber 19 to the plurality of first fuel pipes 13, is injected from the first fuel holes 131, and is premixed with air.

In a specific embodiment, the number of the first cyclones 18 is plural, and the plural first cyclones 18 are stacked in the axial direction L, and each of the first fuel pipes 13 sequentially penetrates through the plural first air passages T1, that is, the first fuel pipes 13 simultaneously penetrate through the sidewalls of the plural first cyclones 18 that are oppositely arranged in the axial direction. The first fuel pipe 13 can fix the plurality of first cyclones 18 at the same time, and has a simple and stable structure, and turbulence lines formed by the surface threads 132 of the first fuel pipe can respectively form turbulence in each first air channel T1. In fig. 5, two first swirlers 18 are arranged between the limiting fixing piece 15 and the annular fuel chamber 19, radial grading level is increased, and two-stage radial swirlers with different swirling strengths and fuel concentrations are created. The length of the first fuel pipe 13 needs to be correspondingly increased, and the number of openings of the first fuel holes 131 is correspondingly increased. Different first swirlers 18 may employ different swirl number first swirler assemblies 182 and different fuel concentration ratios, enabling increased combustor operating mode adaptability, adjustability, and fuel flexibility.

The combustor adopting the two-stage radial swirler can be applied to a low-emission combustion device of a gas turbine.

In a specific embodiment, each adjacent two of the first air passages T1 share a side wall. Specifically, in fig. 5, the first cyclone 18 located on the outer side in the axial direction L includes an inner wall 185 and an outer wall 184, a first air passage T1 is defined between the inner wall 185 and the outer wall 184, and the first cyclone assemblies 182 are disposed in the two first air passages T1, and the first cyclone assemblies 182 include a plurality of first cyclone blades for performing a cyclone action on air or a mixture gas, and the inner wall 185 of the outer side first cyclone 18 and the outer wall 181 of the inner side first cyclone 18 are formed by the same side wall, so that the structure of the first cyclone 18 is facilitated to be simplified.

In a specific embodiment, the combustor assembly 1 further comprises a second fuel pipe 11 and a head igniter 17, the second fuel pipe 11 is located in the second air channel T2, a plurality of second fuel holes 111 are distributed on the circumferential surface (or called cylindrical surface) of the second fuel pipe 11, a vane assembly (specifically, reference may be made to the second swirl assembly 163, and the second swirl assembly 163 includes a plurality of second swirl vanes) is disposed in the second air channel T2, the second fuel holes 111 are located upstream of the vane assembly (reference may be made to the second swirl assembly 163), and an ignition end of the head igniter 17 is located at the second fuel holes 111. The second swirling flow assembly 163 performs swirling flow treatment on the air entering the second air passage T2, the air forming the swirling flow is fully mixed with the fuel sprayed out of the second fuel holes 111 to form mixed gas, so that a semi-premixed combustion mode is formed conveniently, flame stabilization is facilitated, compared with the existing diffusion duty burner, combustion mixing is enhanced, NOx emission is remarkably reduced, and particularly 6 to 10 second fuel holes 111 can be uniformly arranged on the cylindrical surface of the second fuel pipe 11 along the circumferential direction. Because of the small geometry of a common combustion engine, an igniter is arranged on the side wall of a flame tube, and is far away from a fuel spray hole of a combustor, and the problems that the ignition power is not high enough and the ignition boundary is not wide enough in the starting stage exist, and the re-ignition is difficult due to the position of the igniter after flameout due to failure. In the embodiment of the application, the head igniter 17 can increase the ignition success rate and the ignition boundary width, and the on-duty fuel sprayed out of the second fuel hole 111 is instantaneously re-ignited when accidental flameout occurs, so that the ignition failure rate is reduced, and the safety of the unit is improved. For example, the front end of the head igniter 17 is placed above the second fuel hole 111, and the fuel gas is injected into the second air passage T2 through the duty fuel hole 111, and a stable duty flame is generated after being ignited by sweeping the head igniter 17. The duty fuel of the second fuel pipe 11 acts as a stable combustion while burdening the ignition, increasing the normal ignition and thermal start ignition power. The second swirler 16 and the second fuel holes 111 serve as core components of the second burner. The first burner and the second burner are two burners with independent air and fuel passages.

In a specific embodiment, the first fuel hole 131 is formed with a counterbore 133 at the surface opening of the first fuel tube 13, the counterbore 133 having an inner diameter greater than the inner diameter of the first fuel hole 131. Each first fuel pipe 13 is provided with 2 to 4 first fuel holes 131 on each side in the left and right direction of the axial direction L, and 4 to 8 first fuel holes 131 on both sides. The first fuel hole 131 has a counter bore 133 near the surface of the screw thread 132, and the fuel is injected through the first fuel hole 131, and the fuel injection speed is reduced, the injection depth is smaller, and the fuel is fully mixed with the air with high turbulence generated by the screw thread 132 on the surface of the first fuel pipe 13 when flowing out of the first fuel pipe 13, instead of directly injecting the fuel onto the first swirl vane of the first swirl component 182 due to the increase of the aperture of the counter bore 133 relative to the first fuel hole 131. The first swirl vanes of the first swirl assembly 182 are mounted at an angle α of between 40 ° and 70 °, and the angle α can be adjusted as the fuel composition changes to control the residence time of the fuel-air mixture in the first air passage T1.

The embodiment of the application provides a combustion chamber with double igniters based on a dry low-emission combustion lean-burn premixing concept, which can burn conventional natural gas, hydrogen-containing fuel gas, oilfield associated gas, medium-high calorific value synthetic gas and the like.

Based on the same inventive concept, the embodiment of the present application further provides a combustion device, which includes the casing assembly 2, the flame tube assembly 3, and the burner assembly 1 provided in the foregoing embodiment, where the flame tube assembly 3 is located in the casing assembly 2, the flame tube assembly 3 is used as a container of flame, and an opening of a head portion of the flame tube assembly is abutted to an air outlet of the first air channel T1. The inner side wall of the casing assembly 2 is provided with a side wall igniter 21, and the front end of the side wall igniter 21 is flush with the inner wall surface of the flame tube assembly 31 and is used for igniting air-gas mixture in the flame tube assembly 31.

The gas-air mixture of the first air channel T1 enters the flame tube assembly 3 through the air outlet of the first air channel T1 to burn, and the front end of the flame tube assembly 3 is uniformly provided with flame tube cooling air film holes 32 along the circumferential direction to reduce the heat load of the front end wall surface of the flame tube. The front cone section 33 of the head of the burner assembly 3 is capable of generating an external angular recirculation zone to stabilize the flame morphology and continuously providing heat for the unburned gas mixture exiting the burner to ignite rapidly.

The burner assembly 1, the combustion chamber casing assembly 2 and the flame tube assembly 3 are connected through bolts, wherein a flame tube mounting pore plate 31 is arranged at the front end of the flame tube assembly 2, and the flame tube mounting pore plate 31 can serve as a mounting and fixing function and is clamped between the burner head flange 14 and the casing flange 22 of the burner assembly 1. The head of the entire burner assembly 3 is secured against the burner mounting aperture plate 31.

The hole row 34 is arranged on the flame tube mounting hole plate 31, so that the air proportion can be adjusted while the mounting effect is achieved, energy is absorbed through the densely distributed hole row 34 to reduce air pressure fluctuation, and the possibility of combustion oscillation is reduced. Air required for the burner assembly 1 enters the burner assembly 1 through one or more air inlet holes 34 in the liner mounting aperture plate 31.

The head of the second air channel T2 is a bell mouth, the inner wall of which forms an opening with the burner head flange 14 along the radial direction R, and incoming air between the burner cartridge assembly 2 and the flame tube assembly 3 enters the first air channel T1 through a majority of the air inlet hole rows 34 on the flame tube mounting hole plate 31, and another minority enters the second air channel T2.

It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims

1. A burner assembly, comprising: a first swirler and a first fuel pipe, wherein the first swirler has a first air passage, and the first fuel pipe is located in the first air passage;

The surface of the first fuel pipe is provided with flow-turbulating patterns and a plurality of first fuel holes;

The first air channel is a bent structure;

The burner assembly further includes a second swirler and a second fuel pipe, the second swirler having a second air passage, the first air passage surrounding the second air passage; the second fuel pipe is located in the second air passage;

The burner assembly further includes an annular fuel chamber surrounding the second air passage; along the axial direction of the first fuel pipe, a portion of the side wall of the second air passage is located between the side wall of the annular fuel chamber and the bent side wall of the first air passage;

The first fuel pipe passes through two opposite side walls of the first air channel, one end of the first fuel pipe is fixedly connected to and communicates with the annular fuel chamber, and the other end is connected to a limiting fixture via a thread to clamp and fix the side wall of the second air channel.

2. The burner assembly according to claim 1, characterized in that threads are distributed on the circumferential surface of the first fuel pipe;

The portion of the thread of the first fuel pipe located between the two side walls forms the flow-turbulating pattern;

At least one end of the first fuel pipe is connected to a limiting fixing member through the threaded connection.

3. The burner assembly according to claim 2, characterized in that the air inlet of the second air passage faces away from the second air passage, the air outlet of the second air passage surrounds the air outlet of the first air passage, and the first fuel pipe extends in the axial direction.

4 . The burner assembly according to claim 3 , wherein the number of the first fuel pipes is plural, and the plurality of the first fuel pipes are spaced apart and distributed around the second air passage.

5 . The burner assembly according to claim 3 , wherein the number of the first swirlers is plural, the plurality of the first swirlers are stacked in an axial direction, and each of the first fuel pipes passes through a plurality of the first air channels in sequence.

6 . The burner assembly according to claim 5 , wherein every two adjacent first air passages share one side wall.

7. The burner assembly according to claim 3, further comprising a head igniter, wherein a plurality of second fuel holes are distributed on the circumferential surface of the second fuel pipe;

A vane assembly is provided in the second air passage, the second fuel hole is located upstream of the vane assembly, and the ignition end of the head igniter is located at the second fuel hole.

8 . The burner assembly according to claim 1 , wherein a counterbore is formed at a surface opening of the first fuel pipe at the first fuel hole, and an inner diameter of the counterbore is larger than an inner diameter of the first fuel hole.

9. A combustion device, characterized in that it comprises a casing assembly, a flame tube assembly and the burner assembly according to any one of claims 1 to 8, wherein the flame tube assembly is located inside the casing assembly, and an opening of the flame tube assembly is connected to an air outlet of the first air passage.