阅读说明：本技术 双燃料管燃烧室及燃气轮机 (Dual-fuel-tube combustion chamber and gas turbine ) 是由 靳普 刘慕华 于 2021-09-03 设计创作，主要内容包括：本发明公开了一种双燃料管燃烧室及燃气轮机,燃烧室包括火焰筒、点火器、第一旋流器、第二旋流器、第一燃料管、第二燃料管和壳体,火焰筒内腔从前至后依次分为主燃区、次燃区和掺混区,掺混区侧壁设置若干掺混孔；第二旋流器设在火焰筒前端并与其同轴；第一旋流器设在第二旋流器内孔内靠出口端并与其同轴；第一旋流器外侧壁与第二旋流器内孔之间留有间隙；第一燃料管穿过火焰筒前壁并通入第一旋流器,第二燃料管穿过火焰筒前壁并通入第二旋流器；点火器从火焰筒侧壁伸入主燃区；壳体罩设在火焰筒外部,火焰筒与壳体之间设有空气通道。本发明采用双燃料管及双旋流器,使燃料气混合充分,燃料得以充分、持续地燃烧,进而降低排放。(The invention discloses a dual-fuel-tube combustion chamber and a gas turbine, wherein the combustion chamber comprises a flame tube, an igniter, a first swirler, a second swirler, a first fuel tube, a second fuel tube and a shell, the inner cavity of the flame tube is sequentially divided into a main combustion area, a secondary combustion area and a blending area from front to back, and the side wall of the blending area is provided with a plurality of blending holes; the second swirler is arranged at the front end of the flame tube and is coaxial with the flame tube; the first swirler is arranged in the inner hole of the second swirler, close to the outlet end and coaxial with the outlet end; a gap is reserved between the outer side wall of the first swirler and the inner hole of the second swirler; the first fuel pipe penetrates through the front wall of the flame tube and is communicated with the first swirler, and the second fuel pipe penetrates through the front wall of the flame tube and is communicated with the second swirler; the igniter extends into the main combustion area from the side wall of the flame tube; the casing is covered outside the flame tube, and an air channel is arranged between the flame tube and the casing. The invention adopts double fuel pipes and double swirlers, so that fuel gas is fully mixed, the fuel can be fully and continuously combusted, and the emission is reduced.)

1. A dual fuel tube combustor characterized by: the flame tube comprises a flame tube, an igniter, a first swirler, a second swirler, a first fuel pipe, a second fuel pipe and a shell, wherein the inner cavity of the flame tube is sequentially divided into a main combustion area, a secondary combustion area and a blending area from front to back, and a plurality of blending holes are formed in the side wall of the blending area;

the second swirler is arranged at the front end of the flame tube and is coaxial with the flame tube; the first swirler is arranged in the inner hole of the second swirler, close to the outlet end and coaxial with the outlet end; a gap is reserved between the outer side wall of the first swirler and the inner hole of the second swirler;

the first fuel pipe penetrates through the front wall of the flame tube and is communicated with the first swirler, and the second fuel pipe penetrates through the front wall of the flame tube and is communicated with the second swirler;

the igniter extends into the main combustion area from the side wall of the flame tube;

the casing cover is established in the flame tube outside, is equipped with air passage between flame tube and the casing, and air passage's the direction of admitting air is terminal to the front end of flame tube, and air passage's gas outlet and the import of second swirler communicate.

2. The dual fuel tube combustor of claim 1, wherein: and a plurality of air holes are formed in the side walls of the main combustion area and the secondary combustion area.

3. The dual fuel tube combustor of claim 2, wherein: the air holes are obliquely arranged, and the air inlet direction of the air holes is from the front end to the tail end of the combustion chamber.

4. The dual fuel tube combustor of claim 2 or 3, wherein: the included angle between the air hole and the axis of the flame tube is 10-80 degrees;

and/or: the air holes are oblique cylindrical holes, stepped holes or convergent holes.

5. The dual fuel tube combustor of claim 1 or 2, wherein: at least one circle of air holes are arranged on the side walls of the main combustion area and the secondary combustion area in a surrounding manner;

and/or: and at least one circle of mixing holes are arranged on the side wall of the mixing region in a surrounding manner.

6. The dual fuel tube combustor of claim 1, wherein: the first fuel pipe is in threaded connection with the flame tube.

7. The dual fuel tube combustor of claim 1, wherein: the igniter is in threaded connection with the flame tube.

8. The dual fuel tube combustor of claim 1, wherein: the fuel flow ratio of the first fuel pipe to the second fuel pipe is 1: 3-9.

9. The dual fuel tube combustor of claim 2, wherein: the air flow of the air hole accounts for 5-15% of the total flow of the combustion chamber, the air flow of the mixing hole accounts for 39-48% of the total flow of the combustion chamber, the air flow of the first fuel pipe accounts for 2-8% of the total flow of the combustion chamber, and the air flow of the second fuel pipe accounts for 35-50% of the total flow of the combustion chamber.

10. A gas turbine comprising a dual fuel tube combustor as claimed in any one of claims 1 to 9.

Technical Field

The invention relates to a dual-fuel-tube combustion chamber and a gas turbine, and belongs to the technical field of gas turbines.

Background

The gas turbine is a main device consuming natural gas energy and is an indispensable power source in industrial production. As gas turbine grades become higher and higher, gas turbines continue to evolve toward high efficiency and wide load turndown ranges. The method for improving the cycle efficiency is mainly realized by improving the combustion temperature and pressure, and the diffusion type combustion chamber for combusting the fuel with the low and medium calorific values is easy to cause the emission of nitrogen oxides to exceed the standard, so that the realization of stable low-emission combustion in a wide load working condition range is an important performance target of the combustion chamber of the gas turbine.

Disclosure of Invention

In view of the above prior art, the present invention provides a dual fuel tube combustion chamber and a gas turbine that can sufficiently combust fuel and reduce emissions.

The invention is realized by the following technical scheme:

a kind of double fuel pipe combustion chamber, including flame tube, igniter, first swirler, second swirler, first fuel pipe, second fuel pipe and body, the flame tube cavity is divided into main combustion area, secondary combustion area and blending area sequentially from front to back (according to the flow direction of the inlet and outlet gas as the fore-and-aft direction, the inlet side is the front, the outlet side is the back), the sidewall of blending area sets up several mixing holes;

the second swirler is arranged at the front end of the flame tube and is coaxial with the flame tube; the first swirler is arranged in the inner hole of the second swirler, close to the outlet end and coaxial with the outlet end; a gap is reserved between the outer side wall of the first swirler and the inner hole of the second swirler;

the first fuel pipe penetrates through the front wall of the flame tube and is communicated with the first swirler, and the second fuel pipe penetrates through the front wall of the flame tube and is communicated with the second swirler;

the igniter extends into the main combustion area from the side wall of the flame tube;

the casing cover is established in the flame tube outside, is equipped with air passage between flame tube and the casing, and air passage's the direction of admitting air is terminal to the front end of flame tube, and air passage's gas outlet and the import of second swirler communicate.

Further, the main burning zone and the secondary burning zone side wall are provided with a plurality of air holes, and the air holes have the following functions: when the cold air enters, the cold air is diffused to the inner wall of the flame tube from the air holes and forms an air film along the inner wall, so that the wall surface is cooled.

Furthermore, at least one circle of air holes are arranged on the side walls of the main combustion area and the secondary combustion area in a surrounding mode.

Furthermore, the air holes can be obliquely arranged, the air inlet direction of the air holes is from the front end to the tail end of the combustion chamber, and the air inlet direction is consistent with the flowing direction of the combustion mixed gas, so that air flow retardation is avoided.

Furthermore, the included angle between the air hole and the axis of the flame tube is 10-80 degrees.

Further, the air hole may be a slanted cylindrical hole, a stepped hole, or a convergent hole.

Furthermore, at least one circle of mixing holes are arranged on the side wall of the mixing region in a surrounding mode.

Further, the first fuel pipe can be in threaded connection with the flame tube, and the extending distance of the first fuel pipe can be adjusted to prevent the first fuel pipe from being burnt out.

Further, the igniter can be screwed with the flame tube, and the extending distance of the igniter can be adjusted to prevent the igniter from being burnt out.

A gas turbine comprises the double-fuel-tube combustion chamber with the structure, a rotating shaft, a compressor, a turbine and a generator, wherein the compressor, the turbine and the generator are arranged on the rotating shaft.

The working process of the multi-fuel-tube combustion chamber is as follows: air is introduced from the air channel and enters the flame tube in the following mode:

firstly, a part of air enters a mixing area through a mixing hole;

secondly, part of air enters the secondary combustion area and the main combustion area along the inner wall of the flame tube through the air holes to form a layer of adherent gas film, so that the effect of cooling the gas film is achieved, and the wall surface of the flame tube is cooled;

part of the mixed gas enters a second swirler through a second swirler inlet and flows out of swirl vanes of the second swirler;

and fourthly, part of the air flows in through the inner hole inlet of the second swirler and then flows out through the first swirler and the gap.

The fuel enters from the first fuel pipe and is sprayed out from the nozzle of the first fuel pipe, and forms a small rotational flow with the air flowing out of the first swirler at the outlet end of the first swirler; and the fuel enters the second swirler cavity from the second fuel pipe and is discharged from the swirl vanes, and forms a large swirl with the air flowing out of the second swirler at the outlet of the second swirler.

The fuel and the air form rotational flow which can be further mixed fully, the rotational flow is ignited by an igniter, and the rotational flow is discharged from the tail end of the combustion chamber after being combusted in the main combustion area and the secondary combustion area and is introduced into the turbine through the volute; the air entering from the mixing hole can make incompletely burnt fuel fully burn. The first fuel pipe sprays fuel with larger equivalent weight to form a continuous stable flame core in the center of the flame tube, the second fuel pipe is filled with a large amount of fuel to form a strong mixed combustion flame with a large amount of air, and when the flame is extinguished due to excessive carbon and nitrogen compounds generated by a large rotational flow, the continuous flame core can continuously ignite the combustion flame.

Further, the fuel flow ratio of the first fuel pipe to the second fuel pipe is 1: 3-9.

Further, the air flow of the air hole accounts for 5-15% of the total flow of the combustion chamber, the air flow of the mixing hole accounts for 39-48% of the total flow of the combustion chamber, the air flow of the first fuel pipe accounts for 2-8% of the total flow of the combustion chamber, and the air flow of the second fuel pipe accounts for 35-50% of the total flow of the combustion chamber.

The dual-fuel-pipe combustion chamber adopts the dual fuel pipes and the dual cyclones, so that fuel gas is fully mixed, the fuel can be fully and continuously combusted, and the emission is reduced. The side wall of the flame tube is provided with the air holes, so that the wall surface of the flame tube can be cooled and protected from being damaged by high-temperature airflow. The screwing distance of the nozzle and the igniter of the first fuel pipe can be adjusted through the threaded connection, and the first fuel pipe is prevented from being burnt out.

The various terms and phrases used herein have the ordinary meaning as is well known to those skilled in the art. To the extent that the terms and phrases are not inconsistent with known meanings, the meaning of the present invention will prevail.

Drawings

FIG. 1: the structure of the double fuel pipe combustion chamber is shown schematically.

Wherein, 1, a flame tube; 101. a mixing hole; 102. air holes; 2. an igniter; 3. a second swirler; 4. a first swirler; 5. a first fuel pipe; 6. a second fuel pipe; 7. a housing; 701. an air passage; s1: a gap; a: air; b: a fuel; c: hot air; d: small rotational flow; e: a large rotational flow; the direction of the arrows indicates the direction of the air flow.

Detailed Description

The present invention will be further described with reference to the following examples. However, the scope of the present invention is not limited to the following examples. It will be understood by those skilled in the art that various changes and modifications may be made to the invention without departing from the spirit and scope of the invention.

Example 1

A kind of double fuel pipe combustion chamber, including flame tube 1, igniter 2, first swirler 4, second swirler 3, first fuel pipe 5, second fuel pipe 6 and body 7, as shown in figure 1, the inner chamber of flame tube 1 is divided into main combustion area, secondary combustion area and blending area sequentially from front to back (according to the flow direction of the inlet and outlet gas is the fore-and-aft direction, the side of inlet gas is the front, the side of outlet gas is the back), the sidewall of blending area surrounds and sets up a ring of mixing holes 101, the sidewall of main combustion area and secondary combustion area surrounds and sets up a ring of gas holes 102;

the second swirler 3 is arranged at the front end of the flame tube 1 and is coaxial with the flame tube; the first swirler 4 is arranged in the inner hole of the second swirler 3, close to the outlet end and coaxial with the outlet end; a gap S1 is reserved between the outer side wall of the first swirler 4 and the inner hole of the second swirler 3;

the first fuel pipe 5 penetrates through the front wall of the flame tube 1 and is communicated with the first swirler 4, and the second fuel pipe 6 penetrates through the front wall of the flame tube 1 and is communicated with the second swirler 3;

the igniter 2 extends into the main combustion area from the side wall of the flame tube 1;

the casing 7 covers the outer part of the flame tube 1, an air channel 701 is arranged between the flame tube 1 and the casing 7, the air inlet direction of the air channel 701 is from the tail end to the front end of the flame tube 1, and the air outlet of the air channel 701 is communicated with the inlet of the second swirler 3.

The air holes 102 may be arranged diagonally. The function of the air holes 102 is: when cold air enters, the cold air is scattered to the inner wall of the flame tube 1 from the air holes 102 and forms an air film along the inner wall so as to cool the wall surface; the air inlet direction is from the front end to the tail end of the combustion chamber, and the air inlet direction is consistent with the flowing direction of combustion mixed gas, so that air flow blockage is avoided.

The included angle between the air holes 102 and the axis of the flame tube 1 is 10 degrees to 80 degrees, such as 10 degrees, 20 degrees, 30 degrees, 40 degrees, 45 degrees, 50 degrees, 60 degrees, 70 degrees and 80 degrees.

The air hole 102 may be a beveled cylindrical hole, a stepped hole, or a converging hole.

The first fuel pipe 5 may be screwed to the combustor basket 1. The effect of this setting is: since the nozzle of the first fuel pipe 5 is located close to the flame zone, its penetration distance can be adjusted by screwing to prevent burning out.

The igniter 2 can be connected with the flame tube 1 in a threaded mode. The effect of this setting is: since the igniter 2 is located close to the high temperature region, its penetration distance can be adjusted by screwing to prevent burning.

The combustor end outlet is connected to the turbine (not shown) inlet through a volute (not shown).

The working process of the multi-fuel-tube combustion chamber is as follows: air is introduced from the air passage 701 and enters the combustor basket 1 by the following means:

firstly, a part of air enters a mixing area through a mixing hole 101;

secondly, a part of air enters the secondary combustion area and the main combustion area along the inner wall of the flame tube 1 through the air holes 102 to form a layer of adherent gas film, so that the effect of cooling the gas film is achieved, and the wall surface of the flame tube 1 is cooled;

part of the mixture enters the second swirler 3 through an inlet of the second swirler 3 and flows out of the swirl vanes of the second swirler 3;

and fourthly, part of the air flows in through an inner hole inlet of the second swirler 3 and then flows out through the first swirler 4 and the gap S1.

The fuel B enters from the first fuel pipe 5 and is sprayed out from the nozzle thereof, and forms a small swirling flow D at the outlet end of the first swirler 4 together with the air A flowing out of the first swirler 4; the fuel B enters the cavity of the second swirler 3 from the second fuel pipe 6 and is discharged from the swirl vanes, and forms a large swirl E with the air A flowing out of the second swirler 3 at the outlet of the second swirler 3.

The fuel B and the air A form rotational flow which can be further fully mixed, the rotational flow is ignited by the igniter 2, hot air C is discharged from the tail end of the combustion chamber after the combustion in the main combustion area and the secondary combustion area, and the hot air C is introduced into the turbine through the volute; the air a entering the dilution hole 101 can sufficiently burn the incompletely burned fuel B. The first fuel pipe 5 sprays fuel B with larger equivalent ratio to form a continuous stable flame core in the center of the flame tube 1, the second fuel pipe 6 introduces a large amount of fuel B to form a strong mixed combustion flame with a large amount of air A, and when the flame is extinguished due to excessive carbon and nitrogen compounds generated by the large rotational flow E, the continuous flame core can continuously ignite the combustion flame.

In a specific application, the fuel flow ratio of the first fuel pipe 5 to the second fuel pipe 6 can be controlled to be 1: 3-9, such as 1:3,1:4,1:5,1:6,1:7,1:8, and 1: 9.

In specific application, the air flow of the air holes can be controlled to account for 5% -15% of the overall flow of the combustion chamber, the air flow of the mixing holes can be controlled to account for 39% -48% of the overall flow of the combustion chamber, the air flow of the first fuel pipe 5 can be controlled to account for 2% -8% of the overall flow of the combustion chamber, and the air flow of the second fuel pipe 6 can be controlled to account for 35% -50% of the overall flow of the combustion chamber.

More specifically, the air flow rate of the control orifice accounts for 7% of the total flow rate of the combustion chamber, the air flow rate of the control orifice accounts for 43% of the total flow rate of the combustion chamber, the air flow rate of the control first fuel pipe 5 accounts for 5% of the total flow rate of the combustion chamber, and the air flow rate of the control second fuel pipe 6 accounts for 45% of the total flow rate of the combustion chamber.

Example 2

A gas turbine comprises a dual fuel pipe combustion chamber with the structure shown in the embodiment 1, a rotating shaft, a compressor, a turbine and a generator which are arranged on the rotating shaft.

Although the specific embodiments of the present invention have been described with reference to the examples, the scope of the present invention is not limited thereto, and those skilled in the art will appreciate that various modifications and variations can be made without inventive effort by those skilled in the art based on the technical solution of the present invention.