阅读说明：本技术 一种一体化低污染燃烧室喷嘴结构及方法 (Integrated low-pollution combustion chamber nozzle structure and method ) 是由 汪玉明 孙士恩 林俊光 林钢 秦刚华 鲍听 马聪 俞李斌 于 2021-10-08 设计创作，主要内容包括：本发明涉及一体化低污染燃烧室喷嘴结构,包括喷嘴本体、燃料腔体和空气板；空气板焊接在喷嘴本体上形成一体化结构,并且空气板和喷嘴本体采用相同材料；喷嘴本体的喷嘴端部壁面内壁上设有喷嘴导流壁面；燃料腔体主要由喷嘴杆内腔体和喷嘴突扩内腔体相连组成,喷嘴突扩内腔体外侧设有喷嘴导流孔腔体；空气板由空气孔和空气板壁面组成,空气板壁面上均匀分布有空气孔；喷嘴导流孔腔体外侧设有燃料孔。本发明的有益效果是：本发明采用一体式喷嘴结构形式,将空气孔和燃料喷嘴进行结构集成,并采用同种材料加工,能保证在不同的工况下,空气孔和燃料喷嘴保持一致的膨胀变形,保持主要设计尺寸的一致性,使燃料和空气的混合特性与设计结果保持一致。(The invention relates to an integrated low-pollution combustion chamber nozzle structure, which comprises a nozzle body, a fuel cavity and an air plate, wherein the fuel cavity is formed by a plurality of fuel holes; the air plate is welded on the nozzle body to form an integrated structure, and the air plate and the nozzle body are made of the same material; a nozzle flow guide wall surface is arranged on the inner wall of the nozzle end part wall surface of the nozzle body; the fuel cavity is mainly formed by connecting an inner cavity of the nozzle rod with an inner cavity of the nozzle sudden expansion, and a nozzle diversion hole cavity is arranged outside the inner cavity of the nozzle sudden expansion; the air plate consists of air holes and an air plate wall surface, and the air holes are uniformly distributed on the air plate wall surface; the outer side of the cavity of the nozzle diversion hole is provided with a fuel hole. The invention has the beneficial effects that: the invention adopts an integrated nozzle structure form, structurally integrates the air hole and the fuel nozzle, adopts the same material for processing, can ensure that the air hole and the fuel nozzle keep consistent expansion deformation under different working conditions, keeps the consistency of main design dimensions, and ensures that the mixing property of fuel and air keeps consistent with the design result.)

1. The utility model provides a low pollution combustion chamber nozzle structure of integration which characterized in that: comprises a nozzle body (1), a fuel cavity (2) and an air plate (3); the air plate (3) is welded on the nozzle body (1) to form an integrated structure, and the air plate (3) and the nozzle body (1) are made of the same material; a nozzle flow guide wall surface (14) is arranged on the inner wall of the nozzle end part wall surface (13) of the nozzle body (1); the fuel cavity (2) is mainly formed by connecting a nozzle rod inner cavity (21) and a nozzle sudden-expansion inner cavity (22), and a nozzle diversion hole cavity (23) is arranged on the outer side of the nozzle sudden-expansion inner cavity (22); the air plate (3) consists of air holes (31) and an air plate wall surface (32), and the air holes (31) are uniformly distributed on the air plate wall surface (32); fuel holes (15) are formed in the outer side of the nozzle diversion hole cavity (23), the fuel holes (15) are located at the downstream of the air holes (31), and the fuel holes (15) correspond to the air holes (31); the outer edge of the air plate (3) is provided with a circle of air inlet rings (33).

2. The integrated low-pollution combustion chamber nozzle structure of claim 1, wherein: the nozzle body (1) is mainly formed by sequentially connecting a nozzle rod wall surface (11), a nozzle sudden expansion wall surface (12) and a nozzle end part wall surface (13).

3. The integrated low-pollution combustion chamber nozzle structure of claim 1, wherein: the diversion hole cavities (23) are uniformly arranged outside the nozzle sudden-expansion inner cavity (22).

4. The integrated low-pollution combustion chamber nozzle structure of claim 1, wherein: the diversion hole cavity (23) is a cylindrical cavity or a square cavity.

5. The integrated low-pollution combustion chamber nozzle structure of claim 4, wherein: the diameter of the cylindrical cavity is 5% -15% of the diameter of the wall surface (13) at the end part of the nozzle, and the depth of the cylindrical cavity is 20% -30% of the diameter of the wall surface (13) at the end part of the nozzle.

6. The integrated low-pollution combustion chamber nozzle structure of claim 1, wherein: the fuel hole (15) and the outer wall surface of the diversion hole cavity (23) form an acute angle with a certain angle or are vertical to each other.

7. The integrated low-pollution combustion chamber nozzle structure of claim 1, wherein: the proportional relation between the number of the air holes (31) and the number of the fuel holes (15) is 1:1, 1:2 or 1: 3.

8. A method of operating an integrated low-pollution combustor nozzle arrangement as claimed in claim 1, comprising the steps of:

s1, enabling fuel to enter an inner cavity (21) of a nozzle rod from a fuel inlet, then entering an inner cavity (22) of a nozzle sudden expansion and then dividing the inner cavity into two parts, enabling one part to impact a wall surface (13) at the end part of the nozzle along a straight line flow, forming a backflow vortex at the corner of the wall surface (13) at the end part of the nozzle and a flow guide wall surface (14) of the nozzle and flow to a flow guide hole cavity (23) of the nozzle, and finally enabling the fuel to flow out of the nozzle structure from a fuel hole (15) on the outer side of the flow guide hole cavity (23); the other part of the fuel directly flows to the nozzle diversion hole cavity (23), and finally flows out of the nozzle structure from the fuel hole (15) outside the diversion hole cavity (23);

s2, air enters the air hole (31) from the air inlet through the air inlet ring (33), the flow rate is increased, the air and the fuel flowing out from the fuel hole (15) are mixed with each other, and the fuel speed direction is vertical to the air speed direction;

s3, after the fully mixed fuel gas is ignited by the igniter, a plurality of small independently dispersed flames are formed at the downstream of the fuel hole (15).

Technical Field

The invention relates to a nozzle structure, in particular to an integrated low-pollution combustion chamber nozzle structure and a method.

Background

With the shortage of energy and the worldwide emphasis on environmental issues, the requirements of various countries on the pollutant emission performance and combustion efficiency of gas turbines are becoming stricter, and the gas turbines are generally required to be in a load range of more than 50%, and the emission of combustion chambers can be maintained at a low level while maintaining high combustion efficiency. For gaseous fuels (e.g., methane), premixed combustion technology is widely used in order to achieve low emission levels. Although premixed combustion can reach a lower emission level, the mixed gas speed is easily lower than the flame speed due to various faults (nozzle blockage, dirt or design defects) in the running process of the unit, and the combustor is damaged due to backfire.

Patent CN106461211A discloses a combustion device of a gas turbine engine, comprising a nozzle and a burner based on MMX (Micro-Mix) combustion principle. It comprises a plurality of annular portions for fuel injection and annular portions for air guide, the fuel injection components and the air guide components being arranged alternately concentrically, the specific nozzle structure being shown in fig. 5 (which includes a fuel supply pipe 66, an intermediate annular duct 84, nozzle holes 36, nozzle holes 37, a fuel flow path 73). Wherein fuel (hydrogen) enters the nozzle from the intermediate annular conduit 84 and is injected into the downstream liner through nozzle holes 36 and 37; air enters the downstream flame tube through air holes A distributed on the inner side and the outer side; the fuel and the air are vertical to each other and are fully mixed, a plurality of independent small flame structures are formed at the downstream after the fuel and the air are ignited by an igniter, the residence time of the flame can be reduced, the NOx emission can be greatly reduced theoretically, and the occurrence of backfire can be avoided. The nozzle arrangement may be used for the combustion of a variety of fuels, such as natural gas, hydrogen, syngas, and the like. However, the fuel injection part and the air guide part of the nozzle are different components, and deformation displacement and direction may be inconsistent when thermal expansion occurs, so that large relative displacement occurs, and large deviation occurs in the mixing performance of air and fuel, and further flame form is changed, and flame stability and emission performance are deteriorated.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides an integrated low-pollution combustion chamber nozzle structure and a method.

The integrated low-pollution combustion chamber nozzle structure comprises a nozzle body, a fuel cavity and an air plate; the air plate is welded on the nozzle body to form an integrated structure, and the air plate and the nozzle body are made of the same material; a nozzle flow guide wall surface is arranged on the inner wall of the nozzle end part wall surface of the nozzle body; the fuel cavity is mainly formed by connecting an inner cavity of the nozzle rod with an inner cavity of the nozzle sudden expansion, and a nozzle diversion hole cavity is arranged outside the inner cavity of the nozzle sudden expansion; the air plate consists of air holes and an air plate wall surface, and the air holes are uniformly distributed on the air plate wall surface; the outer side of the cavity of the nozzle diversion hole is provided with a fuel hole, the fuel hole is positioned at the downstream of the air hole, and the fuel hole corresponds to the air hole; the outer edge of the air plate is provided with a circle of air inlet ring.

Preferably, the method comprises the following steps: the nozzle body is mainly formed by sequentially connecting a nozzle rod wall surface, a nozzle sudden expansion wall surface and a nozzle end part wall surface.

Preferably, the method comprises the following steps: the flow guide hole cavities are uniformly arranged on the outer side of the inner cavity of the nozzle sudden expansion.

Preferably, the method comprises the following steps: the cavity of the diversion hole is a cylindrical cavity or a square cavity.

Preferably, the method comprises the following steps: the diameter of the cylindrical cavity is 5% -15% of the diameter of the wall surface of the end part of the nozzle, and the depth of the cylindrical cavity is 20% -30% of the diameter of the wall surface of the end part of the nozzle.

Preferably, the method comprises the following steps: the fuel hole and the outer wall surface of the cavity of the flow guide hole form an acute angle with a certain angle or are mutually vertical.

Preferably, the method comprises the following steps: the proportional relationship between the number of air holes and the number of fuel holes is 1:1 or 1:2 or 1: 3.

The working method of the integrated low-pollution combustion chamber nozzle structure comprises the following steps:

s1, enabling fuel to enter an inner cavity of a nozzle rod from a fuel inlet, then entering the inner cavity of a nozzle sudden-expansion and then dividing the inner cavity into two parts, enabling one part to impact the wall surface of the end part of the nozzle along a straight line flow, forming a backflow vortex at the corner of the wall surface of the end part of the nozzle and the flow guide wall surface of the nozzle and flow to the flow guide hole cavity of the nozzle, and finally enabling the fuel to flow out of the nozzle structure from a fuel hole outside the flow guide hole cavity; the other part of the fuel directly flows to the cavity of the nozzle diversion hole and finally flows out of the nozzle structure from the fuel hole outside the cavity of the diversion hole;

s2, air enters the air hole from the air inlet through the air inlet ring, the flow rate is increased, the air and the fuel flowing out from the fuel hole are mixed with each other, and the fuel speed direction is vertical to the air speed direction;

and S3, igniting the fully mixed fuel gas by an igniter, and forming a plurality of small independently dispersed flames at the downstream of the fuel holes.

The invention has the beneficial effects that:

1. the invention adopts an integrated nozzle structure form, structurally integrates the air hole and the fuel nozzle, adopts the same material for processing, can ensure that the air hole and the fuel nozzle keep consistent expansion deformation under different working conditions, keeps the consistency of main design dimensions, and ensures that the mixing property of fuel and air keeps consistent with the design result.

2. The invention adopts an integrated nozzle structure, a plurality of fuel holes in a nozzle unit can share one fuel inlet, and the fuel quantity passing through each fuel hole can be basically consistent through the fine design of the internal flow structure of the fuel channel, so that the fuel uniformity is greatly improved.

Drawings

FIG. 1 is a schematic view of an integrated low pollution combustor nozzle configuration;

FIG. 2 is a sectional view of an integrated low pollution combustor nozzle configuration;

FIG. 3 is a schematic view of the circumferential distribution of air and fuel holes;

FIG. 4 is a schematic view of an integrated low pollution combustor nozzle configuration with an air intake ring;

fig. 5 is a schematic view of a nozzle structure in the related art.

Description of reference numerals: 1. a nozzle body; 11. the wall surface of the nozzle rod; 12. the nozzle expands the wall surface suddenly; 13. a nozzle tip wall surface; 14. a nozzle flow guide wall surface; 15. a fuel hole; 2. a fuel cavity; 21. a nozzle stem internal cavity; 22. the nozzle expands the inner cavity; 23. a nozzle diversion hole cavity; 3. an air plate; 31. an air hole; 32. an air panel wall; 33. and (4) an air inlet ring.

Detailed Description

The present invention will be further described with reference to the following examples. The following examples are set forth merely to aid in the understanding of the invention. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

The integrated low-pollution combustion chamber nozzle structure can ensure the deformation consistency of the air hole and the fuel hole, the fuel mixing characteristic under each working condition is consistent with the design result, and the fuel uniformity of each fuel nozzle can be greatly improved through the fine design of the internal flow structure of the integrated nozzle fuel channel.

Example one

The embodiment of the application provides a low pollution combustion chamber nozzle structure of integration, including nozzle body 1, fuel cavity 2 and air plate 3, forms an independent nozzle unit, and this nozzle unit can independent work, also can form many nozzle structures with other nozzle unit joint work. Wherein, the air plate 3 welds on the nozzle body 1 to adopt the same material (stainless steel, superalloy etc.), also can be through 3D printing technique with nozzle body 1, fuel cavity 2 and the integrated printing of air plate 3. This ensures that the thermal deformation of the nozzle body 1 and the air plate 3 is substantially uniform and does not cause relative displacement with changes in inlet conditions, which may deteriorate the mixing performance of air and fuel.

The nozzle body 1 is mainly formed by sequentially connecting a nozzle rod wall surface 11, a nozzle sudden expansion wall surface 12 and a nozzle end part wall surface 13; a nozzle flow guide wall surface 14 is arranged on the inner wall of the nozzle end part wall surface 13; the fuel cavity 2 is mainly formed by connecting a nozzle rod inner cavity 21 and a nozzle sudden-expansion inner cavity 22, and a nozzle diversion hole cavity 23 is arranged on the outer side of the nozzle sudden-expansion inner cavity 22; the outer side wall of the nozzle body 1 is provided with a circle of air plates 3, each air plate 3 consists of an air hole 31 and an air plate wall surface 32, and the air holes 31 are uniformly distributed on the air plate wall surface 32; the fuel hole 15 is arranged outside the nozzle guide hole cavity 23, the fuel hole 15 is positioned at the downstream of the air hole 31, and the fuel hole 15 corresponds to the air hole 31. A ring of air inlet rings 33 is provided at the outer edge of the air plate 3.

FIG. 3 is a circular distribution of a plurality of air holes in a nozzle unit, the air holes corresponding to fuel holes located downstream of the air holes. The proportional relationship between the air holes and the fuel holes in fig. 4 is 1:1, and the proportional relationship between the air holes and the fuel holes may be 1:2 or 1:3, which is not limited herein.

Fig. 4 shows an integrated nozzle structure with an air inlet ring, and a ring of air inlet rings 33 are added on the outer edge of the air plate 3, and the air inlet rings can make the air flow entering the air holes 31 more uniform and the flow direction more regular. And the air inlet ring can improve the fault tolerance rate of the whole nozzle during assembly, and when the whole nozzle is heated and integrally deforms, the contact area between the nozzle and a combustion chamber can be increased due to the air inlet ring, so that the nozzle cannot be dislocated, and the flame form is greatly changed.

Example two

The diversion hole cavities 23 are uniformly arranged outside the nozzle sudden-expansion inner cavity 22. The cavity of the diversion hole can be a cylindrical cavity or a square cavity. Preferably a cylindrical cavity, more preferably a cylindrical cavity having a diameter of 5% to 15% of the nozzle diameter and a depth of 20% to 30% of the nozzle diameter. The outer wall surface of the diversion hole cavity 23 is provided with fuel holes 15, and the relative positions can form an acute angle with a certain angle and can also be mutually vertical. The diameter of the cavity of the diversion hole is larger than that of the fuel hole, so that the fuel uniformity among different fuel holes can be improved during fuel distribution; the diversion hole cavity 23 is positioned outside the nozzle sudden-expansion inner cavity 22, the depth of the diversion hole cavity is larger than the diameter of the diversion hole cavity, the flow direction of fuel is regular when the fuel flows into the diversion hole cavity, and the fuel distribution uniformity is greatly improved.

EXAMPLE III

FIG. 2 is a sectional view of an integrated low pollution combustor nozzle structure, wherein fuel (methane/hydrogen) enters a nozzle rod inner cavity 21 from a fuel inlet, then enters a nozzle sudden-expansion inner cavity 22 and then is divided into two parts, one part of the fuel is in a straight flow and impacts a nozzle end wall surface 13, a backflow vortex is formed at the corner of the nozzle end wall surface 13 and a nozzle flow guide wall surface 14 and flows to a nozzle flow guide hole cavity 23, and finally the fuel flows out of the nozzle structure from a fuel hole 15 at the tail end of the flow guide hole cavity 23; another portion flows directly to the nozzle pilot hole cavity 23 and finally out of the nozzle structure through the fuel holes 15 at the end of the pilot hole cavity 23. The diversion hole cavity 23 corresponds to the fuel hole 15, and the diversion hole cavity 23 can be a cylinder, a cube, or the like. With a fuel inlet in one nozzle unit, flow uniformity between different fuel orifices 15 can be improved by careful design of the baffle orifice cavities 23. The nozzle structure in this example combines together through backflow vortex and water conservancy diversion hole cavity 23, has improved the flow homogeneity between different fuel holes 15 greatly, and then has guaranteed the local equivalence ratio of nozzle low reaches, prevents that the high temperature hot spot from appearing and then causes local NOx to be higher than usual.

The air enters the air holes 31 from the air inlet, the flow velocity is increased, and the air is mixed with the fuel flowing out from the fuel holes 15, and the mixing between the fuel and the air can be enhanced due to the fact that the fuel velocity direction and the air velocity direction are perpendicular to each other, and the effect similar to premixing is achieved. After the fully mixed fuel gas is ignited by the igniter, a plurality of small flames which are independently dispersed are formed at the downstream of the fuel hole 15, the emission of NOx can be greatly reduced, and the phenomenon of backfire can be avoided because the fuel and the air are positioned in different channels.