Fuel nozzle of gas turbine

Abstract

The invention relates to a fuel nozzle of a gas turbine, which comprises an on-duty path gas pipeline, a main path gas pipeline, a main fuel distribution cavity, an on-duty fuel distribution cavity, a cyclone blade, a main path fuel nozzle and an on-duty gas-air mixing cavity, and a plurality of air holes are formed in the upper part of the outer wall of the on-duty gas-air mixing cavity; a central nozzle is arranged at the bottom of the on-duty fuel-air mixing cavity; the on-duty gas cavity is arranged in the on-duty gas-air mixing cavity, and a plurality of center holes are formed in the bottom of the on-duty gas cavity; gas of an on-duty path enters the on-duty gas-air mixing cavity through the center hole to be mixed with air entering from the air hole and is ignited by the igniter, the fuel is sprayed out through the center nozzle, and pencil type flames are formed when the gas turbine is under the no-load working condition. The problem that in the acceleration process of the gas turbine, especially when the no-load working condition is achieved, flameout is very prone to occurring can be solved; and meanwhile, the fuel-air ratio of the on-duty flame reaches a reasonable numerical value under different load working conditions of the gas turbine, so that the NOx emission of the whole nozzle is greatly reduced.

Description

Technical Field

[0001] The invention relates to the technical field of gas turbines, in particular to a fuel nozzle of a gas turbine. Background Art

[0002] A gas turbine is a heat engine that uses a continuously flowing gas as a working fluid to drive the impeller to rotate at high speed, converting the thermal energy of the fuel into mechanical work. A typical gas turbine consists of three major components: a compressor, a combustion chamber, and a turbine. Among them, the fuel nozzle is an important part of the gas turbine combustion chamber. Its function is to spray fuel into the combustion chamber to burn to release energy, and then output power to the outside through the turbine.

[0003] At present, with the gradual improvement of environmental protection standards, the industry has increasingly stringent restrictions on pollutant emissions from gas turbines, especially ground-based gas turbines. In order to reduce the emission of pollutants such as nitrogen oxides (NOx), dry low-pollution combustion technology has been widely used as a promising energy-saving and environmentally friendly combustion technology. It requires that the fuel and air be mixed as evenly as possible before combustion to ensure that no local high temperatures are generated during combustion, which greatly limits the generation of thermal nitrogen oxides, thereby reducing nitrogen oxide emissions. The above combustion technology places high demands on the fuel mixing performance of the fuel nozzle.

[0004] However, due to the requirements for engine efficiency, in the design of existing gas turbines, a heat preservation structure is usually wrapped around the combustion chamber wall, or a heat recovery gas channel is set around the combustion chamber. This will increase the distance from the gas turbine casing to the combustion chamber interface, resulting in a larger aspect ratio of the fuel nozzle set therebetween, making it difficult for the fuel mixing performance of the fuel nozzle to meet the design requirements. In addition, during the acceleration of the engine, especially when it reaches the no-load condition, the air volume is the largest and the fuel volume is the smallest, and it is very easy to flame out.

[0005] To this end, we propose a gas turbine fuel nozzle. Summary of the invention

[0006] In view of the shortcomings of the above-mentioned existing production technology, the applicant provides a gas turbine fuel nozzle, thereby solving the problem of easy flameout during the acceleration process of the gas turbine, especially when reaching the no-load condition; at the same time, the fuel-air ratio of the duty flame reaches a reasonable value under different load conditions of the gas turbine, thereby significantly reducing the NOx emissions of the entire nozzle.

[0007] The technical solution adopted by the present invention is as follows:

[0008] A gas turbine fuel nozzle, comprising:

[0009] Duty road gas pipeline, used to transport duty road gas;

[0010] Main gas pipeline, used to transport main gas;

[0011] The main fuel distribution chamber is connected with the main gas pipeline;

[0012] The duty fuel distribution chamber is connected to the duty road gas pipeline;

[0013] Swirl blades are arranged below the main fuel distribution chamber and the duty fuel distribution chamber;

[0014] A main fuel nozzle is arranged beside the swirler blades and communicated with the main fuel distribution chamber;

[0015] The duty fuel-air mixing chamber is arranged in the swirler blades, a plurality of air holes are arranged on the upper part of the outer wall of the duty fuel-air mixing chamber, and a central nozzle is arranged at the bottom of the duty fuel-air mixing chamber;

[0016] The duty gas cavity is arranged in the duty fuel-air mixing cavity, the duty gas cavity is connected with the duty fuel distribution cavity, and a plurality of center holes are arranged at the bottom of the duty gas cavity;

[0017] Among them, the duty road gas enters the duty fuel-air mixing chamber through the center hole and mixes with the air entering from the air hole, and is ignited by the igniter. The fuel is sprayed out through the center nozzle to form a pencil-shaped flame when the gas turbine is in no-load condition.

[0018] It is further characterized by:

[0019] It also includes a gas nozzle shell, a nozzle flange is arranged on the top of the gas nozzle shell, a main line rectifier plate and a duty line rectifier plate are arranged on the bottom of the gas nozzle shell, the main line rectifier plate is connected to the main line gas pipeline through the main line pipeline support, and the duty line rectifier plate is connected to the duty line gas pipeline through the duty line pipeline support.

[0020] The main road rectifying plate is provided with a main road rectifying hole, the duty road rectifying plate is provided with a duty road rectifying hole, the main road rectifying hole is connected to the main road gas pipeline, and the duty road rectifying hole is connected to the duty road gas pipeline.

[0021] The same fuel tank seat is arranged below the main road rectifier plate and the duty road rectifier plate, the cavity between the fuel tank seat and the main road rectifier plate is the main fuel distribution cavity, and the cavity between the fuel tank seat and the duty road rectifier plate is the duty fuel distribution cavity.

[0022] An igniter fixing hole is arranged at the center of the fuel tank seat body, the bottom of the igniter is connected to the top of the igniter fixing hole, and the igniter is also connected to the duty road rectifier plate.

[0023] A back plate and a back plate fixing plate are arranged at the bottom of the fuel tank seat body. The back plate fixing plate is arranged on the outer side of the back plate. A back plate hole is opened on the back plate. A duty fuel distribution hole is opened in the middle of the bottom of the duty fuel distribution cavity of the fuel tank seat body. The back plate hole is connected with the duty fuel distribution hole and the duty gas cavity.

[0024] The swirler blades are arranged at the bottom of the back plate, eight bolt holes are opened at the edge of the fuel tank seat body, eight through holes are opened at the edge of the back plate fixing plate, and threaded holes are opened at the bottom of the swirler blades. Bolts connect the swirler blades and the back plate fixing plate to the fuel tank seat body through the threaded holes, through holes and bolt holes.

[0025] A fuel hole is provided on the main fuel nozzle, a main fuel-air mixing chamber is provided in the swirler blade, and the fuel hole is communicated with the main fuel-air mixing chamber.

[0026] A swirler ring is arranged on the outer side of the bottom of the swirler blade, and a nozzle throat is arranged on the inner side of the bottom of the swirler blade.

[0027] The fuel tank seat body is provided with eight small holes at the periphery of the bottom of the main fuel distribution cavity, and the main fuel gas is distributed in the main fuel distribution cavity through the eight small holes.

[0028] The beneficial effects of the present invention are as follows:

[0029] The present invention has a compact and reasonable structure and is easy to operate. During the acceleration process of the gas turbine, especially when it reaches the no-load condition, the amount of air entering from the air hole is the largest, the amount of fuel of the duty gas is the smallest, and the flow rate of the mixed gas is fast. Due to the effect of the duty fuel-air mixing chamber, the flame ejected from the central nozzle is pencil-shaped, has strong stability, is not easily affected by the cold air returned from the main path, and is not easy to extinguish; at the same time, under full-load conditions, the amount of air entering through the air hole is small, the amount of fuel of the duty gas is large, and the flow rate of the mixed gas is slow, which will make the fuel-air ratio of the duty flame reach a reasonable value under different load conditions of the gas turbine, forming a premixed flame, and its NOx emissions will be greatly reduced. Combined with the original premixed flame of the main path, the NOx emissions of the entire nozzle are greatly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a structural schematic diagram of the present invention.

[0031] Figure 2 for Figure 1 Top view of the .

[0032] Figure 3 for Figure 2 Schematic diagram of the AA section.

[0033] Among them: 101, nozzle flange; 102, duty road gas pipeline; 103, duty road gas; 104, igniter; 105, main road gas pipeline; 106, main road gas; 107, gas nozzle shell; 108, main road pipeline support; 109, duty road pipeline support; 110, main road rectifier plate; 111, main road rectifier hole; 112, duty road rectifier plate; 113, duty road rectifier hole; 114, main fuel distribution chamber; 115, duty fuel distribution chamber; 116, fuel tank seat; 117. Duty fuel distribution hole; 118. Igniter fixing hole; 119. Back plate fixing plate; 120. Main fuel nozzle; 121. Fuel hole; 122. Main fuel-air mixing chamber; 123. Swirl blade; 124. Threaded hole; 125. Bolt; 126. Swirl ring; 127. Nozzle throat; 201. Back plate; 202. Back plate hole; 203. Duty fuel-air mixing chamber; 204. Air hole; 205. Duty fuel gas chamber; 206. Center hole; 207. Center nozzle. DETAILED DESCRIPTION

[0034] The specific implementation of the present invention will be described below in conjunction with the accompanying drawings.

[0035] like Figure 1-Figure 3 As shown, a gas turbine fuel nozzle includes a duty line, a main combustion line and an air line, wherein the main combustion line is a gas line located on the outside, the duty line is a gas line located in the middle, and the air line is located on the outermost side. The gas nozzle includes a nozzle flange 101, a gas nozzle housing 107, a duty line gas pipeline 102 and a main line gas pipeline 105, etc. The main line gas 106 is transported through the main line gas pipeline 105, and the duty line gas 103 is transported through the duty line gas pipeline 102.

[0036] The nozzle flange 101 is arranged on the top of the gas nozzle housing 107, and a duty road pipeline support 109 is arranged at one end of the duty road gas pipeline 102, and the duty road gas pipeline 102 and the duty road pipeline support 109 can be connected by brazing. A main road pipeline support 108 is arranged at one end of the main road gas pipeline 105, and the main road gas pipeline 105 and the main road pipeline support 108 can be connected by brazing. A main road rectifying plate 110 is arranged at the bottom of the main road pipeline support 108, and the main road pipeline support 108 and the main road rectifying plate 110 can be connected by brazing. A main road rectifying hole 111 is opened on the main road rectifying plate 110, and the main road rectifying hole 111 is connected to the main road gas pipeline 105. A duty road rectifier plate 112 is provided at the bottom of the duty road pipeline support 109, and the duty road pipeline support 109 and the duty road rectifier plate 112 can be connected by brazing. A duty road rectifier hole 113 is provided on the duty road rectifier plate 112, and the duty road rectifier hole 113 is also connected to the duty road gas pipeline 102. An igniter 104 is provided on the duty road rectifier plate 112, and the igniter 104 and the duty road rectifier plate 112 can be connected by brazing. The main road rectifier plate 110 and the duty road rectifier plate 112 can be connected by brazing.

[0037] The same fuel tank seat 116 is arranged below the main path rectifier plate 110 and the duty path rectifier plate 112. The main path rectifier plate 110 and the fuel tank seat 116 can be connected by brazing, and the duty path rectifier plate 112 and the fuel tank seat 116 can be connected by brazing. The igniter 104 is connected to the fuel tank seat 116, and the igniter 104 and the fuel tank seat 116 can be connected by brazing; an igniter fixing hole 118 is provided in the center of the fuel tank seat 116, and the igniter 104 is connected to the igniter fixing hole 118, and the igniter 104 and the igniter fixing hole 118 can be connected by brazing, which plays a role in fixing the igniter 104. A back plate 201 and a back plate fixing plate 119 are provided at the bottom of the fuel tank seat body 116. The back plate fixing plate 119 is provided on the outer side of the back plate 201. The back plate 201 and the back plate fixing plate 119 can be connected by brazing. The fuel tank seat body 116 and the back plate 201 can be connected by brazing. The fuel tank seat body 116 and the back plate fixing plate 119 can be connected by brazing.

[0038] The back plate fixing plate 119 is provided with a swirler blade 123 at the bottom, and the back plate fixing plate 119 is in contact with the swirler blade 123. The edge of the fuel tank seat body 116 is provided with eight bolt holes, the edge of the back plate fixing plate 119 is provided with eight through holes, and the bottom of the swirler blade 123 is provided with a threaded hole 124. Bolts 125 connect the swirler blade 123 and the back plate fixing plate 119 to the fuel tank seat body 116 through the threaded hole 124, the through hole and the bolt hole.

[0039] A main fuel nozzle 120 is arranged near the swirler blade 123, the main fuel nozzle 120 is connected to the main fuel distribution chamber 114, a fuel hole 121 is provided on the main fuel nozzle 120, a main fuel-air mixing chamber 122 is arranged in the swirler blade 123, and the fuel hole 121 is connected to the main fuel-air mixing chamber 122; a swirler ring 126 is arranged on the outer side of the bottom of the swirler blade 123, and the swirler ring 126 and the swirler blade 123 can be connected by brazing. A nozzle throat 127 is arranged on the inner side of the bottom of the swirler blade 123. The swirler blade 123 and the nozzle throat 127 can be connected by brazing.

[0040] The cavity between the fuel tank seat body 116 and the main road rectifying plate 110 is the main fuel distribution cavity 114, which is connected to the main road gas pipeline 105 through the main road rectifying hole 111. The cavity between the fuel tank seat body 116 and the duty road rectifying plate 112 is the duty fuel distribution cavity 115, which is connected to the duty road gas pipeline 102 through the duty road rectifying hole 113. The fuel tank seat body 116 is provided with a duty fuel distribution hole 117 in the middle of the bottom of the duty fuel distribution cavity 115.

[0041] The fuel tank seat body 116 is provided with eight small holes at the bottom periphery of the main fuel distribution cavity 114 , and the main path gas 106 is distributed in the main fuel distribution cavity 114 through the eight small holes.

[0042] A back plate hole 202 is provided on the back plate 201, and a duty fuel-air mixing chamber 203 and a duty gas chamber 205 are provided at the bottom of the back plate 201. The duty fuel-air mixing chamber 203 and the duty gas chamber 205 are located in the swirler blades 123. The duty gas chamber 205 is provided in the duty fuel-air mixing chamber 203. Eight central holes 206 are provided around the bottom of the duty gas chamber 205. The duty gas chamber 205 is connected to the duty fuel distribution hole 117 through the back plate hole 202. Eight air holes 204 are provided on the upper part of the outer wall of the duty fuel-air mixing chamber 203, and a central nozzle 207 is provided at the bottom of the duty fuel-air mixing chamber 203.

[0043] When the gas turbine is working: the main gas 106 is transported through the main gas pipeline 105, the main gas 106 enters the main fuel distribution chamber 114 through the main rectifying hole 111, and the main gas 106 enters the main fuel nozzle 120 through the eight small holes in the main fuel distribution chamber 114. Then, under the action of the pressure difference, the main gas 106 and the air enter the main fuel-air mixing chamber 122 through the fuel hole 121 for mixing;

[0044] The duty road gas 103 is transported through the duty road gas pipeline 102, and the duty road gas 103 enters the duty fuel distribution chamber 115 through the duty road rectifying hole 113, and enters the duty gas chamber 205 through the duty fuel distribution hole 117 and the back plate hole 202, and then the duty road gas 103 enters the duty fuel-air mixing chamber 203 through the center hole 206, and the duty road gas 103 is mixed with the air entering from the air hole 204. The duty road gas 103 is ignited by the igniter 104, the fuel is discharged through the center nozzle 207, and the flame enters the combustion chamber through the nozzle throat 127, and then ignites the mixed gas of the main road gas 106 and air in the main road fuel-air mixing chamber 122.

[0045] During the acceleration process of the engine, especially when it reaches the no-load condition, the amount of air entering from the air hole 204 is the largest, the amount of fuel in the duty gas 103 is the smallest, and the flow rate of the mixed gas is fast. Due to the action of the duty fuel-air mixing chamber 203, the central nozzle 207 sprays out a pencil-shaped flame, which is more stable, not easily affected by the cold air returned from the main path, and not easy to extinguish; at the same time, under full-load conditions, the amount of air entering through the air hole 204 is smaller, the amount of fuel in the duty gas 103 is larger, and the flow rate of the mixed gas is slow, which will make the fuel-air ratio of the duty flame reach a reasonable value, forming a premixed flame, and its NOx emissions will be greatly reduced. Combined with the original premixed flame of the main path, the NOx emissions of the entire nozzle are greatly reduced.

[0046] The above description is an explanation of the present invention, not a limitation of the present invention. The scope of the present invention is defined in the claims. Any form of modification may be made within the scope of protection of the present invention.

Claims

1. A gas turbine fuel nozzle, It is characterized in that include: A duty road gas pipeline (102), used for transporting duty road gas (103); A main gas pipeline (105) for transporting main gas (106); The main fuel distribution chamber (114) is connected to the main gas pipeline (105); A duty fuel distribution chamber (115) is connected to a duty road gas pipeline (102); Swirl blades (123) are arranged below the main fuel distribution chamber (114) and the duty fuel distribution chamber (115); A main fuel nozzle (120) is arranged beside the swirler blade (123) and communicates with the main fuel distribution chamber (114); A duty fuel-air mixing cavity (203) is arranged in the swirler blade (123), a plurality of air holes (204) are arranged on the upper part of the outer wall of the duty fuel-air mixing cavity (203), and a central nozzle (207) is arranged at the bottom of the duty fuel-air mixing cavity (203); A duty gas cavity (205) is arranged in the duty fuel-air mixing cavity (203), the duty gas cavity (205) is connected to the duty fuel distribution cavity (115), and a plurality of center holes (206) are arranged at the bottom of the duty gas cavity (205); The duty line gas (103) enters the duty fuel-air mixing chamber (203) through the central hole (206) and mixes with the air entering from the air hole (204), and is ignited by the igniter (104). The fuel is ejected through the central nozzle (207) to form a pencil-shaped flame when the gas turbine is in no-load condition.

2. A gas turbine fuel nozzle according to claim 1, Features: It also includes a gas nozzle housing (107), wherein a nozzle flange (101) is arranged on the top of the gas nozzle housing (107), and a main line rectifying plate (110) and a duty line rectifying plate (112) are arranged on the bottom of the gas nozzle housing (107), wherein the main line rectifying plate (110) is connected to the main line gas pipeline (105) via a main line pipeline support (108), and the duty line rectifying plate (112) is connected to the duty line gas pipeline (102) via a duty line pipeline support (109).

3. A gas turbine fuel nozzle as claimed in claim 2, Features: The main road rectifying plate (110) is provided with a main road rectifying hole (111), and the duty road rectifying plate (112) is provided with a duty road rectifying hole (113); the main road rectifying hole (111) is connected to the main road gas pipeline (105), and the duty road rectifying hole (113) is connected to the duty road gas pipeline (102).

4. A gas turbine fuel nozzle according to claim 3, Features: The same fuel tank seat (116) is arranged below the main path rectifying plate (110) and the duty path rectifying plate (112); the cavity between the fuel tank seat (116) and the main path rectifying plate (110) is the main fuel distribution cavity (114); the cavity between the fuel tank seat (116) and the duty path rectifying plate (112) is the duty fuel distribution cavity (115).

5. A gas turbine fuel nozzle as claimed in claim 4, Features: An igniter fixing hole (118) is provided at the center of the fuel tank seat (116); the bottom of the igniter (104) is connected to the top of the igniter fixing hole (118); and the igniter (104) is also connected to the duty road rectifier plate (112).

6. A gas turbine fuel nozzle as claimed in claim 4, Features: The bottom of the fuel tank seat (116) is provided with a back plate (201) and a back plate fixing plate (119), the back plate fixing plate (119) is arranged on the outside of the back plate (201), a back plate hole (202) is opened on the back plate (201), and the fuel tank seat (116) is provided with a duty fuel distribution hole (117) in the middle of the bottom of the duty fuel distribution cavity (115), and the back plate hole (202) is connected with the duty fuel distribution hole (117) and the duty fuel cavity (205).

7. A gas turbine fuel nozzle according to claim 6, Features: The swirler blade (123) is arranged at the bottom of the back plate (201), eight bolt holes are opened at the edge of the fuel tank seat body (116), eight through holes are opened at the edge of the back plate fixing plate (119), a threaded hole (124) is opened at the bottom of the swirler blade (123), and bolts (125) are connected to the swirler blade (123) and the back plate fixing plate (119) on the fuel tank seat body (116) through the threaded hole (124), the through hole and the bolt hole.

8. A gas turbine fuel nozzle according to claim 7, Features: The main fuel nozzle (120) is provided with a fuel hole (121), a main fuel-air mixing chamber (122) is provided in the swirler blade (123), and the fuel hole (121) is communicated with the main fuel-air mixing chamber (122).

9. A gas turbine fuel nozzle according to claim 8, Features: A swirler ring (126) is arranged on the outer side of the bottom of the swirler blade (123), and a nozzle throat (127) is arranged on the inner side of the bottom of the swirler blade (123).

10. A gas turbine fuel nozzle according to claim 9, Features: The fuel tank seat body (116) is provided with eight small holes at the periphery of the bottom of the main fuel distribution cavity (114), and the main fuel gas (106) is distributed in the main fuel distribution cavity (114) through the eight small holes.

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