CN115355529B

CN115355529B - Combustion chamber

Info

Publication number: CN115355529B
Application number: CN202210940193.3A
Authority: CN
Inventors: 韩啸; 王智辉; 严熙成; 林宇震; 张弛
Original assignee: Beihang University
Current assignee: Beihang University
Priority date: 2022-08-05
Filing date: 2022-08-05
Publication date: 2023-08-11
Anticipated expiration: 2042-08-05
Also published as: CN115355529A

Abstract

The invention relates to the technical field of combustion, and discloses a combustion chamber, which comprises: the flame tube assembly is characterized in that a nozzle structure is arranged at the first end of the flame tube assembly, the nozzle structure comprises a mounting cover plate connected with the flame tube assembly and at least one nozzle unit arranged on the mounting cover plate, the nozzle unit comprises a plurality of nozzle channels, an axial nozzle is further arranged on the flame tube assembly, and the axial nozzle is arranged at the downstream position at intervals relative to the nozzle structure. The invention provides a combustion chamber, which is provided with a nozzle structure comprising a plurality of nozzle channels with smaller size, so that the mixing scale of fuel and oxidant can be reduced, the micro-mixed combustion of fuel is realized to reduce emission, meanwhile, the high-speed jet of the nozzle channels has strong backfire resistance and flexible fuel adaptability, in addition, the axial nozzle is provided with an axial staged combustion technology, the emission can be reduced by adjusting the distribution proportion of fuel working media, and meanwhile, the high-efficiency working load range of the combustion chamber can be widened, and meanwhile, the high-speed jet of the nozzle channels has certain flexible fuel adaptability.

Description

Combustion chamber

Technical Field

The invention relates to the technical field of combustion, in particular to a combustion chamber.

Background

The gas turbine is one of important equipment in the field of energy power at present, the traditional gas turbine mainly uses natural gas as fuel, but under the traction of a low-carbon emission target, in a future low-carbon clean energy ecological system, flexible fuel which mainly uses hydrogen and is mixed with other gas fuels such as carbon monoxide, short-chain alkane and the like is a main way for the gas turbine to realize low-carbon and even zero-carbon power generation. However, due to the active chemical properties of flexible fuels such as hydrogen fuel, the problem of spontaneous combustion tempering oscillation caused by directly using the hydrogen fuel in the traditional natural gas low-emission combustion chamber is remarkable, and a new combustion technology is required.

The existing combustion chamber has the problems that the existing combustion chamber is not suitable for flexible combustion of hydrogen and the like and has poor fuel adaptability.

Disclosure of Invention

The invention provides a combustion chamber which is used for solving the problems that the existing combustion chamber is not suitable for flexible combustion such as hydrogen and the like and has poor fuel adaptability.

The present invention provides a combustion chamber comprising: the flame tube assembly is characterized in that a nozzle structure is arranged at the first end of the flame tube assembly, the nozzle structure comprises a mounting cover plate connected with the flame tube assembly and at least one nozzle unit arranged on the mounting cover plate, the nozzle unit comprises a plurality of nozzle channels, an axial nozzle is further arranged on the flame tube assembly, and the axial nozzle is arranged at the downstream part at intervals relative to the nozzle structure.

According to the combustion chamber provided by the invention, the flame tube assembly comprises a flame tube body and a flame tube guide bushing arranged at the periphery of the flame tube body, wherein a first gap is formed between the flame tube body and the flame tube guide bushing;

the second end of the flame tube assembly is connected with a transition section assembly, the transition section assembly comprises a transition section body connected with the second end of the flame tube body and a transition section guide bushing arranged on the periphery of the transition section body, a second gap is arranged between the transition section body and the transition section guide bushing, and the second gap is communicated with the first gap; and the transition section guide bushing is provided with cooling holes, and the cooling holes are used for introducing medium for cooling.

According to the combustion chamber provided by the invention, the outer wall of the flame tube body is provided with the reinforced heat exchange structure.

The combustion chamber provided by the invention further comprises a pipeline system, wherein the pipeline system comprises an end cover and a connecting pipe, one end of the connecting pipe is connected with the end cover, the other end of the connecting pipe is connected with the nozzle channel, the periphery of the connecting pipe is provided with a switching section, one end of the switching section is connected with the end cover, the other end of the switching section is connected with the first end of the flame tube assembly, and the inner space of the switching section is communicated with the first gap;

the device comprises a nozzle channel, wherein a plurality of first air inlets are arranged on the nozzle channel, the first air inlets are used for introducing various reaction components, a medium introduced by a cooling hole is one of the reaction components, the inner space of the nozzle channel is communicated with the inner space of the switching section through one of the first air inlets, and the other first air inlets are connected with the connecting pipes in one-to-one correspondence.

According to the combustion chamber provided by the invention, the peripheries of the flame tube assembly and the transition section assembly are provided with the combustion pressure cylinder, and the second gap is communicated with the inside of the combustion pressure cylinder through the cooling hole;

The gas inlet device comprises an axial nozzle, a plurality of cooling holes, a plurality of gas inlets and a gas inlet pipe, wherein the second gas inlets are arranged on the axial nozzle and are used for introducing various reaction components, a medium introduced by the cooling holes is one of the reaction components, the inner space of the axial nozzle is communicated with the inner space of the gas pressure cylinder through one of the second gas inlets, and the other second gas inlets are correspondingly connected with the gas inlet pipe.

According to the combustion chamber provided by the invention, when a plurality of nozzle units are arranged on the mounting cover plate, an acoustic baffle is arranged between two adjacent nozzle units;

and/or a plurality of the nozzle units are arranged flush or at intervals in the axial direction.

According to the combustion chamber provided by the invention, a plurality of nozzle channels on the nozzle unit are arranged according to Pei Bona-U-F spiral.

According to the combustion chamber provided by the invention, the plurality of first air inlets are arranged at intervals in the axial direction of the nozzle channel, and the first air inlets positioned at the downstream part are used for introducing reaction components with higher density.

According to the combustion chamber provided by the invention, the axial nozzle comprises a hollow nozzle body, a plurality of second air inlets are arranged at intervals in the axial direction of the nozzle body, and the second air inlets positioned at the downstream part are used for introducing reaction components with higher density.

According to the combustion chamber provided by the invention, at least one second air inlet is formed in the side wall of the nozzle body, a plurality of spokes are arranged in the nozzle body at positions corresponding to the second air inlet, the spokes are arranged along the radial direction of the nozzle body, the spokes are of hollow structures, the spokes are communicated with the second air inlet, and the spokes are provided with reaction component outlets.

The invention provides a combustion chamber, which is provided with a nozzle structure comprising a plurality of nozzle channels with smaller size, so that the mixing scale of fuel and oxidant can be reduced, the micro-mixed combustion of fuel is realized to reduce emission, meanwhile, the high-speed jet of the nozzle channels has strong backfire resistance and flexible fuel adaptability, in addition, the axial nozzle is provided with an axial staged combustion technology, the emission can be reduced by adjusting the distribution proportion of fuel working media, and meanwhile, the high-efficiency working load range of the combustion chamber can be widened, and meanwhile, the high-speed jet of the nozzle channels has certain flexible fuel adaptability.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the following description will briefly explain the drawings used in the embodiments or the description of the prior art, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of the overall structure of a combustion chamber provided by the present invention;

FIG. 2 is a schematic illustration of an enhanced heat exchange structure provided by the present invention;

FIG. 3 is a schematic diagram of a second heat exchange enhancement structure according to the present invention;

FIG. 4 is a schematic view of a combustion chamber head structure provided by the present invention;

FIG. 5 is a schematic illustration of the distribution of nozzle units on a mounting cover plate according to the present invention;

FIG. 6 is a second schematic diagram of the distribution of nozzle units on the mounting cover plate according to the present invention;

FIG. 7 is a third schematic view of the distribution of nozzle units on the mounting cover plate according to the present invention;

FIG. 8 is a schematic view of the axial position of a nozzle unit provided by the present invention;

FIG. 9 is a schematic view of combustor load modulation provided by the present invention;

FIG. 10 is a schematic view of a combustion chamber flame structure provided by the present invention;

FIG. 11 is a schematic illustration of the dimensions of a nozzle channel in a nozzle unit provided by the present invention;

FIG. 12 is a schematic polar view of a nozzle unit provided by the present invention;

FIG. 13 is a schematic view of flame classification when a nozzle unit is provided on the mounting cover plate according to the present invention;

FIG. 14 is a schematic view of a nozzle channel provided by the present invention;

FIG. 15 is a schematic cross-sectional view of a nozzle channel provided by the present invention;

FIG. 16 is a schematic view of an axial nozzle provided by the present invention;

fig. 17 is a schematic cross-sectional view of an axial nozzle provided by the present invention.

Reference numerals:

11 and 14: a connecting flange; 12 and 13: a first air inlet pipe; 21: an end cap; 22: a transfer section; 23: a connecting pipe; 24: a combustion pressure cylinder; 25: an air intake diffuser; 31: a nozzle unit; 311: a nozzle channel; 311a: an on-duty area; 311b: a first level region; 311c: a secondary region; 311d: a tertiary region; 3111. 3112 and 3113: a first air inlet; 3114: a cyclone; 32: an acoustic baffle; 33: installing a cover plate; 41: a flame tube guide sleeve; 42: a flame tube body; 43: reinforcing a heat exchange structure; 431: rib-shaped reinforced heat exchange structure; 432: dot matrix reinforced heat exchange structure; 44: a transition section guide bushing; 45: a cooling hole; 46: a transition section body; 51: an axial nozzle; 511: a nozzle body; 5111 and 5112: a second air inlet; 512: spokes; 513: a reaction component outlet; 514: a central shaft; 52 and 53: and a second air inlet pipe.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some embodiments of the present invention, 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.

The combustion chamber of the present invention is described below in conjunction with fig. 1-17.

Referring to fig. 1, the present embodiment provides a combustion chamber including: the flame tube assembly, the first end of flame tube assembly is equipped with the nozzle structure, the nozzle structure with the installation apron 33 that the flame tube assembly is connected and set up at least one nozzle unit 31 on the installation apron 33, nozzle unit 31 includes a plurality of nozzle passageway 311, still be equipped with axial nozzle 51 on the flame tube assembly, axial nozzle 51 is relative the nozzle structure interval is located the low reaches position.

In this embodiment, a nozzle structure is disposed at the head of the flame tube assembly, and an axial nozzle 51 is disposed at the downstream portion of the flame tube assembly, that is, a nozzle structure and an axial nozzle 51 two-stage nozzle are disposed along the flame flow direction, so that axial staged combustion can be realized. The axial nozzle 51 is located downstream, i.e. the axial nozzle 51 is located downstream with respect to the nozzle structure, from where the flame flows towards the axial nozzle 51. Further, the nozzle structure specifically comprises a plurality of nozzle channels 311, and the nozzle channels 311 are micro-mixing channels, i.e. micro-mixing combustion can be realized at the nozzle structure.

The combustion chamber provided in this embodiment is provided with a nozzle structure including a plurality of nozzle channels 311 with smaller dimensions, which can reduce the mixing scale of fuel and oxidant, so as to realize micro-mixed combustion of fuel to reduce emission, and meanwhile, the high-speed jet of the nozzle channels 311 has strong anti-backfire capability and flexible fuel adaptability, in addition, the axial nozzle 51 is provided with an axial staged combustion technology, and the distribution proportion of fuel working medium can be adjusted, so that emission is reduced, and meanwhile, the high-efficiency working load range of the combustion chamber can be widened, and meanwhile, the high-speed jet has certain flexible fuel adaptability.

The combustion chamber provided by the embodiment adopts a micro-mixing coupling axial classification technology, can realize flexible fuel such as hydrogen and the like, and has high efficiency, safety, low emission combustion, wide working load range and quick load adjustment, and good fuel adaptability.

Further, a plurality of axial nozzles 51 may be uniformly disposed along the circumference of the liner assembly.

Further, referring to fig. 1, the flame tube assembly includes a flame tube body 42 and a flame tube guiding liner 41 disposed at the periphery of the flame tube body 42, and a first gap is formed between the flame tube body 42 and the flame tube guiding liner 41; a second end of the flame tube assembly is connected with a transition section assembly, the transition section assembly comprises a transition section body 46 connected with the second end of the flame tube body 42 and a transition section guide bushing 44 arranged on the periphery of the transition section body 46, a second gap is arranged between the transition section body 46 and the transition section guide bushing 44, and the second gap is communicated with the first gap; the transition section guide bushing 44 is provided with cooling holes 45, and the cooling holes 45 are used for introducing medium for cooling.

In this embodiment, the cooling hole 45 is formed in the transition piece guiding bush 44, and the medium enters the second gap between the transition piece guiding bush 44 and the transition piece body 46 from the cooling hole 45 to cool the transition piece body 46, and then flows from the second gap to the first gap to cool the flame tube body 42. In this embodiment, the cooling medium is adopted to perform convective heat exchange between the transition section body 46 and the outer side of the flame tube body 42, so that the reaction quenching of cold air to the near wall area in the flame tube body 42 caused by directly opening the cooling hole 45 on the flame tube body 42 can be avoided, and the emission of CO and the like can be further reduced.

Further, on the basis of the above embodiment, the outer wall of the flame tube body 42 is provided with a reinforced heat exchange structure 43. The heat exchange enhancing structure 43 is used for enhancing the convection heat exchange of the cooling medium outside the flame tube body 42, so as to enhance the cooling effect on the flame tube body 42.

Specifically, referring to fig. 2, the heat exchange enhancement structure 43 may be a rib-shaped heat exchange enhancement structure 431, i.e. rib-shaped protrusions may be disposed on the outer wall of the flame tube body 42 to enhance the convective heat exchange of the cooling medium in the first gap; the cross-sectional shape of the rib-like projections includes, but is not limited to, rectangular, triangular, trapezoidal, or the like. Referring to fig. 3, the heat exchange enhancement structure 43 may be a lattice-shaped heat exchange enhancement structure 432, i.e. lattice-shaped protrusions may be further disposed on the outer wall of the flame tube body 42 to enhance the convective heat exchange of the cooling medium in the first gap; the shape of the lattice-like projections includes, but is not limited to, a cylinder or an elliptic cylinder, etc.

In other embodiments, the heat exchange enhancing structure 43 may be other structures, such as grooves on the outer wall of the flame tube, and the specific arrangement is not limited, so as to enhance the heat convection of the cooling medium in the first gap.

On the basis of the above embodiment, further, referring to fig. 1 and 4, a combustion chamber further includes a pipe system, the pipe system includes an end cap 21 and a connecting pipe 23, one end of the connecting pipe 23 is connected with the end cap 21, the other end of the connecting pipe 23 is connected with the nozzle channel 311, a switching section 22 is disposed on the periphery of the connecting pipe 23, one end of the switching section 22 is connected with the end cap 21, the other end of the switching section 22 is connected with the first end of the flame tube assembly, and the inner space of the switching section 22 is communicated with the first gap. The piping system is used to introduce the reactive components into the nozzle structure.

Specifically, at the head of the flame tube assembly, an installation space is formed by enclosing the end cover 21 and the adapter section 22 with the flame tube assembly, the nozzle structure is arranged in the installation space, and is fixedly connected with the flame tube assembly through the installation cover plate 33, and the connecting pipe 23 is arranged in the installation space and is connected with the nozzle channel 311 for introducing reaction components into the nozzle channel 311.

Further, the nozzle channel 311 is provided with a plurality of first air inlets, the plurality of first air inlets are used for introducing a plurality of reaction components, the medium introduced by the cooling hole is one of the reaction components, the internal space of the nozzle channel 311 is communicated with the internal space of the adapter section 22 through one of the first air inlets, and the other first air inlets are connected with the connecting pipes 23 in a one-to-one correspondence.

That is, in this embodiment, the internal space of the adaptor section 22 is communicated with the first gap, and a first air inlet on the nozzle channel 311 is disposed in the internal space of the adaptor section 22, so that a reaction component can be introduced from the cooling hole 45 as a cooling medium, flows through the second gap and the first gap in sequence, then enters the internal space of the adaptor section 22, and then enters the interior of the nozzle channel 311 through the first air inlet on the nozzle channel 311. Other first air inlets on the nozzle passage 311 may introduce other reaction components one by one through the connection pipe 23. The reaction components are introduced into the nozzle passage 311 through the first air inlet, mixed in the nozzle passage 311, and then sprayed into the flame tube body 42 for combustion.

In particular, the reaction components typically include a fuel and an oxidant, and some combustion processes require not only the fuel, the oxidant, but also some environmental media for creating an environment suitable for combustion. For example, hydrogen-based flexible fuels tend to burn too rapidly and tend to cause localized high temperature zones, so that the environmental medium is diluted by the addition of air, but not limited to air, or by the use of diluents such as steam or inert gases, and the fuel oxidant may be supplied separately as desired, so that some combustion processes require three reaction components. In other embodiments, the three reaction components are not limited to being a fuel, an oxidant, and a diluent; the fuel, the oxidant, the catalyst and the like can be used, and the specific types of the components are not limited.

When the combustion process includes two reaction components, i.e., fuel and oxidant, one of the reaction components may flow through the second gap and the first gap through the cooling holes 45 and then flow into the inside of the nozzle passage 311, and the other reaction component may be introduced into the nozzle passage 311 through the connection pipe 23. When the combustion process includes three or more reaction components, one of the reaction components may flow through the second gap and the first gap through the cooling holes 45 and then flow into the inside of the nozzle passage 311, and the other reaction components may be introduced into the nozzle passage 311 through the respective corresponding connection pipes 23.

In this embodiment, a reaction component is adopted as a cooling medium to be introduced from the cooling hole 45, so that not only can the reaction component be utilized to realize cooling of the flame tube body 42 and the transition section body 46, but also the reaction component can be introduced at different positions, and the reaction component is prevented from being mixed in advance, thereby reducing the risk of ignition in advance and being beneficial to improving the combustion safety.

In other embodiments, the medium introduced into the cooling hole may be other working media, that is, other working media than the reaction components of the combustion process, and the reaction components may all be introduced into the nozzle channel 311 through the connection pipe 23. The specific kind of the cooling medium is not limited.

Further, referring to fig. 1, a first air inlet pipe is connected to one end of the end cover 21 facing away from the connecting pipe 23, and the first air inlet pipe is disposed in one-to-one correspondence with the connecting pipe 23. The first air inlet pipe is used for introducing reaction components.

Specifically, in the present embodiment, the first air inlet pipe 12 and the first air inlet pipe 13 may be provided for introducing two reaction components, and the first air inlet pipe 12 and the first air inlet pipe 13 are respectively connected with corresponding connection pipes 23, and the reaction components are introduced into the nozzle passage 311 through the connection pipes 23. The first air inlet pipe may be provided with a connection flange 11 at one end and a connection flange 14 at the other end, and may be connected to the end cap 21 through the connection flange 14.

Further, on the basis of the above embodiment, the peripheries of the flame tube assembly and the transition section assembly are provided with a combustion cylinder 24, and the second gap is communicated with the interior of the combustion cylinder 24 through the cooling hole 45; i.e., the burner assembly and the transition piece assembly are disposed in the interior space of the combustion cylinder 24. The cooling medium may be introduced through the combustion cylinder 24 and then through the cooling holes 45 into the second gap. Specifically, referring to FIG. 1, the combustion cylinder 24 may be provided with an intake diffuser 25, with the intake diffuser 25 being the cooling medium inlet.

Further, the axial nozzle 51 is provided with a plurality of second air inlets, the second air inlets are used for introducing a plurality of reaction components, the medium introduced by the cooling holes is one of the reaction components, the internal space of the axial nozzle 51 is communicated with the internal space of the combustion cylinder 24 through one of the second air inlets, and the other second air inlets are correspondingly connected with an air inlet pipe.

That is, in the present embodiment, the axial nozzle 51 is provided on the flame tube assembly, the axial nozzle 51 is located in the internal space of the combustion cylinder 24, and a second air inlet provided on the axial nozzle 51 is located in the internal space of the combustion cylinder 24, so that a reaction component can be introduced from the combustion cylinder 24 as a cooling medium, and the reaction component in the combustion cylinder 24 can enter the interior of the axial nozzle 51 through the second air inlet provided on the axial nozzle 51. Other second air inlets on the axial nozzle 51 may introduce other reaction components one by one through the second air inlet pipe. The reaction components are introduced into the axial nozzle 51 through the second air inlet, mixed in the axial nozzle 51, and then sprayed into the flame tube body 42 for combustion.

Specifically, referring to fig. 1, in the present embodiment, a second air inlet pipe 52 and a second air inlet pipe 53 may be provided for introducing two reaction components into the axial nozzle 51, and the second air inlet pipe 52 and the second air inlet pipe 53 may extend to the end cover 21 and pass out of the end cover 21 so as to be connected to an air supply line.

Further, referring to fig. 4, when the mounting cover 33 is provided with a plurality of nozzle units 31, an acoustic baffle 32 is disposed between two adjacent nozzle units 31; fig. 4 shows that an acoustic diaphragm 32 is installed between each nozzle unit 31 for suppressing thermo-acoustic oscillations that may occur.

And/or a plurality of the nozzle units 31 are disposed flush or spaced apart in the axial direction.

Referring to fig. 5, 6 and 7, on the mounting cover plate 33, the nozzle units 31 may be arranged as required, the number of the nozzle units 31 is not limited, and the distribution form includes, but is not limited to, a multi-layer circumferential distribution. The axial distribution position of each nozzle unit 31 with reference to fig. 8 is flexibly adjustable, and is not limited to flush distribution. Specifically, the incoming flow direction is axial, and the reaction components flow axially into the flame tube body 42 along the nozzle channel 311. Fig. 8 a shows a schematic view of the axially flush distribution of the individual nozzle units 31; fig. 8 b and c show distribution diagrams of the nozzle units 31 arranged at intervals in the axial direction, and the nozzle unit 31 located in the middle in the b shows a distance Δl from the other nozzle units 31 in the axial direction. The specific distribution pitch of each nozzle unit 31 in the axial direction is not limited.

Further, the axial nozzles 51 may be uniformly distributed along the circumference of the flame tube assembly, and the number of the axial nozzles 51 may be 1-10. Defining the axial position coefficient of the axial nozzle 51 on the liner assembly is: the axial distance of the axial nozzle 51 from the first end of the flame tube assembly divided by the total length of the flame tube assembly results in a coefficient of position of the axial nozzle 51 of 0.3-0.9.

Further, when the plurality of nozzle units 31 are provided on the mounting cover 33, the plurality of nozzle units 31 may be activated in stages. As shown in fig. 9, the combustion load can be divided into four working conditions of M1, M2, M3 and M4, wherein the nozzle units 31 with cross-hatching in the figure are schematic of the nozzle units 31 opened under different working conditions; under the small working conditions such as starting ignition, only the fuel valve of the central nozzle unit 31 is opened, the fuel of each nozzle unit 31 is supplied step by step along with the increase of the working conditions, the working conditions continue to be increased, and the axial classification is opened, so that the aim of high-efficiency low-emission combustion is fulfilled under a wide load range, and meanwhile, the fuel valve has the capability of rapid load adjustment. The flame structure of the combustion chamber in full load operation is shown in fig. 10, the head is a compact micro-mixed flame, and the downstream is an axial jet flame.

Further, with reference to fig. 11, the plurality of nozzle passages 311 of the nozzle unit 31 are arranged in a Pei Bona-deed train-fermat spiral manner on the basis of the above-described embodiment. For each nozzle unit 31, a plurality of nozzle channels 311 are included, and this embodiment proposes that the plurality of nozzle channels 311 in each nozzle unit 31 are arranged in a fibonacci-fermat spiral. I.e. the plurality of nozzle channels 311 in the nozzle unit 31 are arranged in a spiral, and the spiral arrangement is specifically arranged in a fibonacci-fermat spiral. This spiral arrangement is similar to that of natural sunflowers, so that the nozzle passages 311 are spirally distributed, by which not only uniformity among the nozzle passages 311 in the circumferential direction of the nozzle unit 31 can be improved, but also uniformity of the nozzle passages 311 in the radial direction of the nozzle unit 31 can be advantageously improved, thereby improving uniformity of the overall distribution of the nozzle passages 311 on the nozzle unit 31, as shown in fig. 11 and 12.

According to the combustor nozzle structure provided by the embodiment, the plurality of nozzle channels 311 are arranged according to fibonacci series-Fermat spiral, so that the nozzle channels 311 are uniformly distributed in the circumferential direction and the radial direction of the nozzle unit 31, the overall distribution uniformity of the nozzle channels 311 on the nozzle unit 31 is improved, the uniformity of fuel distribution in space is improved, a local high-temperature area is avoided, the stability and the combustion performance of flame can be effectively improved, and the combustion effect is ensured. Meanwhile, due to the good uniformity of the nozzle passage 311, only one nozzle unit 31 with a larger size can be used in the combustion chamber to replace the existing plurality of smaller nozzle units 31, so that the combustion performance is better when the size of the combustion chamber is larger.

On the basis of the above embodiment, further, the fibonacci series-fermat spiral arrangement is specifically:

where, referring to fig. 11, r is a distance between the center of the nth nozzle passage 311 and the center of the nozzle unit 31, which can be obtained by the above formula. c is a size coefficient; depending on the size of the combustion chamber, it may be set; specifically, c may be 0.6-2 times the diameter of the nozzle channel 311. n is a natural number, and can be from 1, then take 2, 3, 4 to get the position information of n nozzle channels 311. α is a rotation angle of the nth nozzle passage 311 and the (n+1) th nozzle passage 311 with respect to the center of the nozzle unit 31; 0< alpha <360 deg., different arrangements can be obtained by changing the angle value, and the angle value can be used in different combustion chambers as appropriate.

Referring to fig. 12, the position of the center of each nozzle passage 311 may be determined by means of polar coordinates; specifically, a polar coordinate system is constructed with the center of the nozzle unit 31, i.e., the center of the circle, as the zero point, where r is the polar radius; θ is the polar coordinate angle. The center, or center, of the nth nozzle channel 311 may be expressed as R equal to R and θ equal to the remainder of n x α divided by pi. The coordinate positions of the first to nth nozzle passages 311 are sequentially obtained.

Further, based on the above examples, α in the fibonacci-fermat helical arrangement is 50 ° -300 °. The fibonacci series-fermat spiral arrangement within the angle range has high uniformity, different arrangement can be obtained by different angle values, and specific angle values can be specifically designed according to practical application conditions without limitation.

For example, α in a fibonacci-fermat spiral arrangement can be 69 °, 85.4 °, 137.5 °, 179 °, 222.5 °, or 274.6 °. The present embodiment specifically provides six different α value examples, where fibonacci series-fermat spiral arrangement under the six α values has higher uniformity in the circumferential direction and the radial direction, so that the uniformity of the overall distribution of the nozzle channels 311 is higher, so as to obtain a better combustion effect.

Alternatively, α in the fibonacci array-fermat spiral arrangement can be 69 °, 85.4 °, 137.5 °, 222.5 °, or 274.6 °, with better distribution uniformity. Fig. 11 and 12 show schematic views of a 137.5 deg.. In other embodiments, α in the fibonacci array-fermat spiral arrangement can take other values, and can be flexibly selected according to a specific combustion chamber design and a combustion condition, and is not particularly limited.

Further, with reference to fig. 11, the diameter d of the nozzle channel 311 is: 2-14mm. The diameter d of the nozzle channel 311 can be selected according to the working condition of the combustion chamber, the nozzle channel 311 with the size range can realize better mixing of reaction components, and the size of a single nozzle channel 311 is smaller, so that the mixing scale of fuel and air can be reduced to realize micro-mixing combustion. In other embodiments, the size of the nozzle channel 311 may be other, and is not limited in particular.

Further, referring to fig. 13, when one nozzle unit 31 is provided on the mounting cover 33, the nozzle channel 311 of the nozzle unit 31 in the central area is set as a duty area 311a, the nozzle channels 311 on the periphery of the duty area 311a sequentially include a plurality of groups of classification areas along the circumferential direction, and any group of classification areas includes a plurality of different stage areas sequentially provided along the circumferential direction;

The duty area 311a is used for being opened under all combustion conditions; the plurality of different stage areas are for selectively opening according to combustion conditions. The plurality of different stage areas are specifically used to increase the number of stages of opening in accordance with an increase in the combustion load.

The multiple nozzle channels 311 in the nozzle unit 31 provided in this embodiment are arranged according to fibonacci series-fermat spiral, so that the distribution uniformity of the nozzle channels 311 in the circumferential direction and the radial direction can be improved, interference among the channels is reduced, the spatial uniformity of injected fuel can be improved, and the generation of local high-temperature regions can be avoided. Meanwhile, due to the good uniformity of the nozzle unit 31, only one nozzle unit 31 with a larger size can be used in the combustion chamber to replace the existing plurality of smaller micro-mixing nozzle units 31, and accordingly, the fuel regulation mode is changed.

Specifically, the plurality of nozzle channels 311 located at the central part of the nozzle unit 31 are divided into an on-duty area 311a, and the on-duty area 311a is used for being opened under all working conditions; the attendant region 311a may be circular. The nozzle passages 311 on the periphery of the duty area 311a are divided into a plurality of groups which are sequentially connected in the circumferential direction; each group comprises a plurality of areas of different levels, namely each group is divided into a plurality of areas, the levels of the areas are different from each other, and the areas of the different levels are sequentially connected in the circumferential direction.

For example, referring to fig. 13, the present embodiment takes 4 stages as an example: the innermost ring is an on-duty area 311a, namely on-duty flame, and works under all working conditions; the remaining nozzle passage 311 is divided into a primary zone 311b, i.e., a 1-stage flame zone, a secondary zone 311c, i.e., a 2-stage flame zone, and a tertiary zone 311d, i.e., a 3-stage flame zone, according to the spiral. Sequentially supplying air according to the load, and operating all the nozzle channels 311 at full load; the nozzle channels 311 of the pilot flame zone and the stage 1, 2 flame zone operate at medium load. Therefore, the fuel can be distributed as uniformly as possible after being sprayed out under all working conditions, and the 1, 2 and 3-level flame areas are connected with the on-duty flame area, so that the working load of the combustion chamber can be changed rapidly.

Further, with reference to fig. 14, on the basis of the above-described embodiment, a plurality of the first air inlets are provided at intervals in the axial direction of the nozzle passage 311, and the first air inlets located at the downstream portion are used for introducing the reaction components having a larger density. I.e. a plurality of first gas inlets, introduce different reaction components at different locations of the nozzle channel 311. The first gas inlet at the downstream portion introduces a reaction component having a higher density than the reaction component introduced at the upstream portion.

In this embodiment, the nozzle channel 311 is hollow and is used for flowing a plurality of reaction components, and the flow direction of the reaction components in the nozzle channel 311 is from the upstream part to the downstream part. The denser reaction component is introduced at a downstream location such that in nozzle passage 311 the denser reaction component is injected into the flowing other reaction component for blending. In the embodiment, the reaction components with higher density are arranged at the downstream and sprayed into the mixture for mixing, so that the jet penetration capability of the reaction components with higher density is higher, and compared with the method that the components with lower density are mixed into the components with higher density in an expanding way, the method can improve the mixing uniformity of the reaction components and the mixing effect by using the diffusion mixing of the reaction components with higher density, thereby being beneficial to reducing local high temperature areas in the subsequent combustion process, inhibiting combustion oscillation and improving the combustion effect.

In the embodiment, the reaction components are sprayed at intervals, so that the risk of spontaneous combustion tempering caused by early mixing of the reaction components is avoided, and the combustion safety is ensured. The nozzle structure is suitable for traditional fuels such as natural gas, flexible fuels such as hydrogen, and the like, and has strong fuel adaptability and high safety.

Further, in this embodiment, three first air inlets are provided on the nozzle channel 311; one of the first air inlets 3111 is provided on an end face of the nozzle passage 311, the other first air inlet 3113 is provided on a side wall of the nozzle passage 311 near an upstream portion, and the other first air inlet 3112 is provided on a side wall of the nozzle passage 311 near a downstream portion; wherein the density of the reaction component introduced into the first gas inlet 3112 at the downstream portion is maximized.

In this example, when there are three reaction components, two reaction components having relatively small densities are introduced at an upstream site, preliminarily mixed at the upstream, and then flowed downstream. The reaction components with relatively high density are introduced and diffused into the mixed gas from the downstream, and finally the three reaction components are mixed and then sprayed out from the downstream. In the embodiment, the two reaction components are firstly mixed, then the third reaction component is mixed, and the three reaction components are mixed step by step, so that ordered mixing of the reaction components can be realized, the combustion safety is improved, and the mixing effect is guaranteed; and the reaction components with higher density are used for diffusion blending at the downstream, which is beneficial to improving the blending uniformity.

Further, referring to fig. 15, the nozzle passage 311 has an inner diameter D1 of 3-20mm at one end at the downstream portion.

Further, a mixed flow structure is provided inside the nozzle passage 311 between the first end and the second end. Specifically, the mixed flow structure may be a cyclone 3114. The cyclone 3114 is provided between the first intake port 3113 and the first intake port 3112. So that the two reaction components at the upstream portion are mixed and then further mixed by the cyclone 3114 to ensure mixing uniformity.

Further, the swirl number of the cyclone 3114 is 0.1 to 0.4. Further, other mixed flow structures, such as mixed flow ribs, may be provided between the first end and the second end of the nozzle channel 311, for the purpose of enhancing the mixing between the first component and the third component, and are not particularly limited.

Further, on the basis of the above embodiment, the axial nozzle 51 includes a hollow nozzle body 511, a plurality of the second air inlets are provided at intervals in the axial direction of the nozzle body 511, and the second air inlets located at the downstream portion are used for introducing the reaction components having a greater density. I.e. the arrangement of the second air inlet on the axial nozzle 51 is similar to the arrangement of the first air inlet on the nozzle channel 311. The plurality of second air inlets introduce different reaction components at different locations of the nozzle body 511. The second gas inlet at the downstream portion introduces a reaction component having a higher density than the reaction component introduced by the second gas inlet at the upstream portion.

In this embodiment, the nozzle body 511 has a hollow structure for flowing a plurality of reaction components, and the flow direction of the reaction components in the nozzle body 511 is from the upstream portion to the downstream portion. The denser reactive species is introduced at a downstream location such that in nozzle body 511 the denser reactive species is injected into the flowing other reactive species for blending. In the embodiment, the reaction components with higher density are arranged at the downstream and sprayed into the mixture for mixing, so that the jet penetration capability of the reaction components with higher density is higher, and compared with the method that the components with lower density are mixed into the components with higher density in an expanding way, the method can improve the mixing uniformity of the reaction components and the mixing effect by using the diffusion mixing of the reaction components with higher density, thereby being beneficial to reducing local high temperature areas in the subsequent combustion process, inhibiting combustion oscillation and improving the combustion effect.

Further, referring to fig. 16 and 17, at least one second air inlet is provided on a side wall of the nozzle body 511, a plurality of spokes 512 are provided in the nozzle body 511 at positions corresponding to the second air inlet, the spokes 512 are disposed along a radial direction of the nozzle body 511, the spokes 512 are hollow structures, and the spokes 512 are all communicated with the second air inlet, and the spokes 512 are provided with reaction component outlets 513.

That is, the second gas inlet may be provided on the end surface of the nozzle body 511, and the reaction components may be directly introduced from the end surface of the nozzle body 511; the second gas inlet may also be provided on a sidewall of the nozzle body 511, from which the reaction components are introduced. At least one second gas inlet may be provided on the sidewall of the nozzle body 511, and at this time, since the inner diameter of the nozzle body 511 is large, in order to ensure uniform diffusion and mixing of the reaction components introduced from the second gas inlet, a spoke 512 structure may be provided inside the nozzle body 511, the reaction components may be introduced into the spoke 512 through the second gas inlet on the sidewall of the nozzle body 511, and then introduced into the inside of the nozzle body 511 through the reaction component outlet 513 on the spoke 512.

Further, referring to fig. 17, in this embodiment, three second air inlets are provided on the nozzle body 511; one of the second air inlets is arranged on the end face of the nozzle body 511, the other second air inlet 5112 is arranged on the side wall of the nozzle body 511 near the upstream part, and the other second air inlet 5111 is arranged on the side wall of the nozzle body 511 near the downstream part; spokes 512 are respectively arranged in the nozzle body 511 corresponding to the second air inlets 5111 and the second air inlets 5112, and reaction outlets are arranged on the spokes 512. Wherein the density of the reaction component introduced through the second gas inlet 5111 at the downstream portion is maximized.

Further, a plurality of reaction component outlets 513 may be provided on each spoke 512. The inner diameter D2 of the nozzle body 511 is 20-80mm. The first ends of the spokes 512 are collectively connected to a central shaft 514 at the middle portion of the nozzle body 511, and the second ends of the spokes 512 are connected to the side wall of the nozzle body 511. Channels, which may be annular channels, may be provided in the sidewall of the nozzle body 511 and respectively communicate with the plurality of spokes 512, and the channels are connected to the second air inlet to introduce the reaction components into the plurality of spokes 512.

Based on the above embodiment, further, based on the current situation that the conventional natural gas combustion chamber cannot realize safe and efficient combustion of flexible fuel mainly comprising hydrogen fuel, the micro-mixed combustion technology is considered to realize hydrogen fuel combustion, but because the micro-mixed combustion technology has no backflow area structure, the low-load stability is poor, meanwhile, because the flame is more compact, high-frequency combustion oscillation is easy to generate, and the high-efficiency working load range is not wide enough. The embodiment provides a flexible fuel low-emission combustion chamber with micro-mixing head and axial staged coupling, which can burn conventional fuels such as natural gas and the like, can realize the safe and efficient low-emission combustion of flexible fuels mainly comprising hydrogen fuel, and has wider and efficient working load range and rapid load adjustment capability.

The flexible fuel low-emission combustion chamber with the head micro-mixing coupling axial grading provided by the embodiment is composed of a connecting pipeline system, a combustion cylinder system, a head combustor, a flame tube assembly and an axial grading combustor.

Referring to fig. 1 and 4, the connection pipe system includes a connection flange 11, a first intake pipe 12, a first intake pipe 13, and a connection flange 14; the fuel pressure cylinder system comprises an end cover 21, an adapter section 22, a connecting pipe 23, a fuel pressure cylinder 24 and an air inlet diffuser 25; the head burner comprises a nozzle unit 31, an acoustic baffle 32, a mounting cover 33; the flame tube assembly comprises a flame tube guide sleeve 41, a flame tube body 42, an enhanced heat exchange structure 43, a transition section guide sleeve 44, cooling holes 45 and a transition section body 46; the axially staged burner comprises an axial nozzle 51, an axially staged fuel pipe, i.e. a second inlet pipe 52, an axially staged oxidant pipe, i.e. a second inlet pipe 53.

The incoming flow working medium can be a diluent such as water vapor, and the like, enters the combustion pressure cylinder 24 through the air inlet diffuser 25, and most of the working medium performs impact cooling on the transition section 46 from the impact cooling hole 45 of the transition section, then flows through the flame tube reinforced heat exchange structure 43 to perform reinforced convection cooling on the flame tube body 42, and enters the head micro-mixing nozzle; a small portion of the working fluid enters the liner body 42 from the axial nozzle 51.

The head and the axially graded fuel enter from the end cover 21, the head flexible fuel and the oxidant can enter the head micro-mixed combustion nozzle through the first air inlet pipe 12, the first air inlet pipe 13, the connecting pipe 23 and the axially graded fuel pipe and the axially graded oxidant pipe respectively.

In other embodiments, if the incoming working fluid is air, i.e., air is used as a diluent, and the air is used as an oxidant, no additional oxidant is needed, and the air enters the nozzle passage from the combustion cylinder and the axial nozzle 51, the nozzle passage may be connected to a first air intake pipe, and the axial nozzle 51 may be connected to a second air intake pipe, so as to introduce the fuel.

As shown in fig. 2 and 3, the wall surface of the flame tube is provided with a reinforced heat exchange structure 43, which can be an annular strip distributed rib, and the cross section of the flame tube can be a lattice distributed flow-around column structure including but not limited to a cylinder, an elliptic column and the like, and the cross section of the flame tube can be a rectangular rib, a triangular rib, a trapezoid rib and the like. By enhancing convection heat exchange, the reaction quenching of cold air on a near wall area in the flame tube caused by directly opening a cooling hole on the flame tube is avoided, and the emission of CO and the like is further reduced.

The grading low-emission combustion chamber provided by the embodiment adopts a grading strategy of head micro-mixing coupling axial grading, and sequentially opens each stage along with the increase of working conditions, so that the grading low-emission combustion chamber has a wide load efficient working range and quick adjustment capability; useful flexible fuels include natural gas, hydrogen, alkanes, and the like; the working medium can be air, but is not limited to air, and can also use diluents such as water vapor, and the fuel oxidant can be independently supplied according to the requirement; the number and the distribution of the micro-mixing nozzles at the head can be arranged according to the requirements, the axial position of each nozzle can be flexibly adjusted, and a certain height of acoustic baffle plates are arranged between the micro-mixing nozzles to inhibit combustion oscillation; the number of the axial classification nozzles is 1-10 in the circumferential direction of the periphery of the flame tube, and the axial position coefficient of the axial classification nozzles is 0.3-0.9; the impact and intensified convection heat exchange cooling structure is adopted, and the wall surface of the flame tube is not provided with cooling holes, so that reaction quenching caused by cold air is avoided. The reinforced heat exchange structure may take various forms, such as ribs, flow-around columns, etc. The ribs are not limited to rectangular triangular trapezoids, and the flow-around columns are not limited to cylinders or elliptic columns.

The embodiment adopts a head micro-mixing coupling axial grading combustion organization mode, has strong fuel adaptability, is suitable for traditional fuels such as natural gas and the like, can realize high-efficiency combustion of flexible fuels mainly comprising hydrogen fuel, and realizes low-carbon and even zero-carbon emission; the self-ignition tempering and combustion oscillation can be effectively inhibited, the combustion safety is ensured, and simultaneously, compared with a single micro-mixed combustion technology, the self-ignition tempering and combustion oscillation control device has a wider high-efficiency working load range and a load rapid adjustment capability.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A combustion chamber, comprising: the flame tube comprises a pipeline system and a flame tube assembly, wherein a nozzle structure is arranged at the first end of the flame tube assembly, the nozzle structure comprises a mounting cover plate connected with the flame tube assembly and at least one nozzle unit arranged on the mounting cover plate, the nozzle unit comprises a plurality of nozzle channels, an axial nozzle is further arranged on the flame tube assembly, and the axial nozzle is arranged at a downstream part at intervals relative to the nozzle structure;

The flame tube assembly comprises a flame tube body and a flame tube guide bushing arranged at the periphery of the flame tube body, and a first gap is formed between the flame tube body and the flame tube guide bushing; the second end of the flame tube assembly is connected with a transition section assembly, the transition section assembly comprises a transition section body connected with the second end of the flame tube body and a transition section guide bushing arranged on the periphery of the transition section body, a second gap is arranged between the transition section body and the transition section guide bushing, and the second gap is communicated with the first gap; the transition section diversion bushing is provided with cooling holes which are used for introducing medium for cooling;

the pipeline system comprises an end cover and a connecting pipe, one end of the connecting pipe is connected with the end cover, the other end of the connecting pipe is connected with the nozzle channel, a switching section is arranged on the periphery of the connecting pipe, one end of the switching section is connected with the end cover, the other end of the switching section is connected with the first end of the flame tube assembly, and the inner space of the switching section is communicated with the first gap; the nozzle channel is provided with a plurality of first air inlets, the first air inlets are used for introducing a plurality of reaction components, the medium introduced by the cooling holes is one of the reaction components, the inner space of the nozzle channel is communicated with the inner space of the switching section through one of the first air inlets, and the other first air inlets are correspondingly connected with the connecting pipes one by one;

The peripheries of the flame tube assembly and the transition section assembly are provided with a combustion pressure cylinder, and the second gap is communicated with the inside of the combustion pressure cylinder through the cooling hole; the axial nozzle is provided with a plurality of second air inlets, the second air inlets are used for introducing a plurality of reaction components, the medium introduced by the cooling holes is one of the reaction components, the inner space of the axial nozzle is communicated with the inner space of the combustion pressure cylinder through one of the second air inlets, and the other second air inlets are correspondingly connected with an air inlet pipe;

the axial nozzle comprises a hollow nozzle body, a plurality of second air inlets are arranged at intervals in the axial direction of the nozzle body, and the second air inlets positioned at the downstream part are used for introducing reaction components with higher density; at least one second air inlet is arranged on the side wall of the nozzle body, a plurality of spokes are arranged in the nozzle body at positions corresponding to the second air inlet, the spokes are arranged along the radial direction of the nozzle body, the spokes are of hollow structures, the spokes are communicated with the second air inlet, and a reaction component outlet is arranged on each spoke.

2. The combustor according to claim 1, wherein the outer wall of the flame tube body is provided with a reinforced heat exchange structure.

3. The combustion chamber according to any one of claims 1 or 2, wherein when a plurality of the nozzle units are provided on the mounting cover plate, an acoustic baffle is provided between two adjacent nozzle units;

4. The combustion chamber according to any one of claims 1 or 2, wherein a plurality of said nozzle channels on said nozzle unit are arranged in a Pei Bona-chef array-fermat spiral.

5. The combustion chamber according to claim 1, wherein a plurality of said first air inlets are provided at intervals in an axial direction of said nozzle passage, and said first air inlets located at downstream portions are for introducing a reaction component having a higher density.