A gas turbine combustor ultra-low emission duty spray nozzle and method of use

Abstract

The application discloses a kind of gas turbine combustor ultra-low emission value shift nozzle and its use method.The value shift nozzle includes center body and value fuel spray rod, center body includes blunt body neck, value fuel spray rod includes spray rod inner ring and spray rod outer ring, spray rod outer ring is sleeved in blunt body neck, spray rod inner ring is sleeved in spray rod outer ring, there is tail end closure between spray rod inner ring and spray rod outer ring, the tail end of spray rod outer ring is equipped with a plurality of value fuel injection holes, the inside of spray rod inner ring forms cooling airflow channel, value fuel passage is formed between spray rod inner ring and spray rod outer ring, airflow channel for fuel mixing is formed between spray rod outer ring and blunt body neck.The use method is directed to the above-mentioned gas turbine combustor ultra-low emission value shift nozzle, to adjust each working state of nozzle.The beneficial effects of the application are: realize stable flame, ultra-low NOx emission, inhibit backfire and thermal acoustic oscillation, ensure the stability of gas turbine operation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of gas turbine combustor, and particularly relates to a gas turbine combustor ultra-low emission duty nozzle and a use method thereof, which can realize stable flame, ultra-low NOx emission, suppression of backfire and thermal acoustic oscillation, and guarantee the stability of gas turbine operation. BACKGROUND

[0002] Dry Low NOx (DLN) combustion technology is a mature technology for controlling pollutant emission which is universally adopted by mainstream heavy-duty gas turbines in the world. In the DLN combustion technology, the sufficient mixing of fuel and air in the main nozzle provides lean premixed combustion to control the main combustion zone temperature, thereby reducing NOx emission. However, the lean premixed combustion will introduce thermal acoustic oscillation problem due to its low temperature, resulting in backfire, blowout, over-temperature and other phenomena. Therefore, in order to compensate for the above shortcomings of lean premixed combustion, a duty nozzle is usually introduced to provide local diffusion combustion to improve flame stability and ensure stable operation of the unit.

[0003] However, the introduction of duty diffusion flame will bring NOx emission problem due to its high combustion temperature and poor mixing uniformity, especially under low load conditions of the gas turbine; in addition, it will also cause new problems of combustion instability, over-temperature, backfire and the like due to the change of local thermal load. SUMMARY

[0004] The present application provides a gas turbine combustor ultra-low emission duty nozzle and a use method thereof, which solves a series of problems such as poor mixing, unstable combustion, over-temperature, backfire and the like caused by the introduction of duty nozzle.

[0005] The present application achieves the above-mentioned purpose through the following technical solutions.

[0006] A gas turbine combustor ultra-low emission duty nozzle, comprising a center bluff body and a duty fuel injection rod, the center bluff body comprises a bluff body neck, the duty fuel injection rod comprises an inner ring and an outer ring, the outer ring is sleeved in the bluff body neck, the inner ring is sleeved in the outer ring, there is a tail end sealing part between the inner ring and the outer ring, the tail end of the outer ring is provided with a plurality of duty fuel injection holes, the inner part of the inner ring forms a cooling gas flow channel, a duty fuel channel is formed between the inner ring and the outer ring, and a gas flow channel for fuel mixing is formed between the outer ring and the bluff body neck.

[0007] Further, the center bluff body further comprises a bluff body end ring and an arc-shaped transition part, the center of the bluff body end ring is connected with the head end of the bluff body neck through the arc-shaped transition part, and the duty fuel injection rod further comprises a rod end ring, the center of the rod end ring is connected with the head end of the outer ring.

[0008] Furthermore, the blunt body neck, the inner ring of the spray bar, and the outer ring of the spray bar are all cylindrical structures, and the three are arranged along the same axis.

[0009] Furthermore, the blunt body neck is also provided with a blunt body tail cone ring at the tail end.

[0010] Furthermore, the tail end faces of the inner and outer rings of the spray bar are flush with the tail end platform of the blunt body neck.

[0011] Furthermore, the duty fuel injection holes are arranged at an angle from the front inside to the rear outside.

[0012] Furthermore, the blunt end ring is connected to the burner head by bolts, and the spray rod end ring is also connected to the burner head by bolts.

[0013] Furthermore, the blunt end ring is provided with a fuel mixing airflow inlet and a radial channel. The fuel mixing airflow inlet penetrates the inner and outer surfaces of the blunt end ring and is connected to the radial channel. The radial channel is located between the blunt end ring and the burner head and is connected to the fuel mixing airflow channel.

[0014] Furthermore, the cooling airflow channel is equipped with an ignition hydrant and a flame detector.

[0015] A method for using an ultra-low emission duty nozzle for a gas turbine combustor, specifically addressing the aforementioned ultra-low emission duty nozzle for a gas turbine combustor: By adjusting the diameter, number, and incident angle of the duty fuel injection holes, as well as the flow rate of the duty fuel mixed air and the size of the gap between the central blunt body and the duty fuel injection rod, the premixing performance of the duty fuel and air and the jet depth of the duty fuel can be adjusted, thereby controlling the position, shape, and size of the duty flame, reducing NOx generation, and suppressing backfire; By adjusting the axial length of the duty fuel injection rod and the central blunt body, the overall axial distribution of the flame can be controlled, improving flame stability; By adjusting the outer diameter and fillet of the central blunt body, the outlet velocity of the main nozzle can be controlled, thereby achieving the goals of constraining the flame position and shape, suppressing backfire, and preventing blow-out; By adjusting the air volume of the cooling air at the center of the duty fuel injection rod, the shape of the outlet cross-section, the number of holes, the hole diameter, and the incident angle, effective cooling can be formed at the nozzle tip, preventing overheating and backfire.

[0016] The beneficial effects of this invention are: achieving stable flame, ultra-low NOx emissions, suppressing backfire and thermoacoustic oscillations, and ensuring the operational stability of the gas turbine.

[0017] The aforementioned main solution of the present invention and its various further alternative solutions can be freely combined to form multiple solutions, all of which are solutions that can be adopted and are claimed by the present invention; furthermore, the (non-conflicting alternatives) can also be freely combined with each other and with other alternatives. Those skilled in the art, after understanding the solution of the present invention, will realize from the prior art and common general knowledge that there are many combinations, all of which are technical solutions to be protected by the present invention, and will not be exhaustively listed here. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the present invention.

[0019] Figure 2 This is a schematic diagram of the structure of the central blunt body of the present invention.

[0020] Figure 3 This is a schematic diagram of the structure of the shift fuel injector of the present invention.

[0021] Figure 4 yes Figure 3 A sectional view along the AA direction.

[0022] Figure 5 This is an installation diagram of the present invention.

[0023] In the diagram: 1-Central blunt body, 2-Stationary fuel injector rod, 3-Blunt body end ring, 4-Blunt body neck, 5-Blunt body tail cone ring, 6-Inner ring of injector rod, 7-Outer ring of injector rod, 8-Tail end sealing part, 9-Stationary fuel injection hole, 10-Cooling airflow channel, 11-Stationary fuel channel, 12-Fuel mixing airflow channel, 13-Burner head, 14-Bolt, 15-Injector rod end ring, 16-Fuel mixing airflow inlet, 17-Radial channel, 18-Arc-shaped transition part. Detailed Implementation

[0024] The following non-limiting examples are used to illustrate the present invention.

[0025] Example 1

[0026] refer to Figures 1-5 As shown, an ultra-low emission duty nozzle for a gas turbine combustor includes a central blunt body 1 and a duty fuel injection rod 2.

[0027] The central blunt body 1 includes an integrally formed blunt end ring 3, a blunt neck 4, a blunt tail cone ring 5, and an arc-shaped transition portion 18. The blunt end ring 3 is an annular plate-like structure, and the blunt neck 4 is a cylindrical structure. The blunt end ring 3 is arranged perpendicularly to the axis of the blunt neck 4. The center of the blunt end ring 3 is connected to the head end of the blunt neck 4 through the arc-shaped transition portion 18. The tail end of the blunt neck 4 is also provided with a blunt tail cone ring 5, and the inner surface of the blunt tail cone ring 5 is a trumpet-shaped structure facing the tail end.

[0028] The standby fuel injector 2 includes an integrally formed inner ring 6, an outer ring 7, a tail end seal 8, standby fuel injection holes 9, and an end ring 15. The center of the end ring 15 is connected to the beginning of the outer ring 7. Both the inner ring 6 and the outer ring 7 are cylindrical structures. The inner ring 6 is fitted inside the outer ring 7, and the tail end seal 8 is located between the inner ring 6 and the outer ring 7. The tail end of the outer ring 7 is provided with several standby fuel injection holes 9, which are evenly arranged in a circle. The standby fuel injection holes 9 are arranged at an angle from the front inside to the rear outside, and the fuel injection holes inject into the main stream at a certain incident angle.

[0029] The blunt neck 4, the inner ring 6 of the spray bar, and the outer ring 7 of the spray bar are arranged along the same axis. The outer ring 7 of the spray bar is fitted inside the blunt neck 4. The tail end faces of the inner ring 6 and the outer ring 7 of the spray bar are flush with the tail end platform of the blunt neck 4.

[0030] The inner ring 6 of the spray bar forms a cooling airflow channel 10 to fully cool the nozzle tip, while also accommodating components such as the ignition pin and flame detector. A standby fuel channel 11 is formed between the inner ring 6 and the outer ring 7 of the spray bar, through which fuel enters the flame tube from multiple fuel nozzles located at the tail end of the standby fuel spray bar. A fuel mixing airflow channel 12 is formed between the outer ring 7 of the spray bar and the blunt body neck 4. Mixed air flows out through this channel and, at the tail cone ring of the central blunt body, is fully mixed with the standby fuel by the jet flow, transforming the pure diffusion flame into a semi-premixed flame. This significantly improves NOx emissions from the standby diffusion flame while ensuring flame stability. This nozzle structure extends deep into the flame tube, pushing the flame downstream and effectively preventing backfire.

[0031] The blunt end ring 3 is provided with a fuel mixing airflow inlet 16 and a radial channel 17. The fuel mixing airflow inlet 16 penetrates the inner and outer surfaces of the blunt end ring 3. The fuel mixing airflow inlet 16 is connected to the radial channel 17. The radial channel 17 is located between the inner surface of the blunt end ring 3 and the burner head 13. The radial channel 17 is connected to the fuel mixing airflow channel 12.

[0032] The blunt body end ring 3 is connected to the burner head 13 by bolts 14, and the spray rod end ring 15 is connected to the burner head 13 by bolts 14, thereby realizing the fixed installation of the central blunt body 1 and the shift fuel spray rod 2 on the burner to achieve their functions.

[0033] Example 2

[0034] refer to Figures 1-5 As shown, a method for using an ultra-low emission duty nozzle for a gas turbine burner is described, specifically for the ultra-low emission duty nozzle for a gas turbine burner in Example 1.

[0035] By adjusting the diameter, number, and incident angle of the standby fuel nozzles, as well as the flow rate of the standby fuel-air mixture, the size of the gap between the central blunt body and the standby fuel nozzle rod, the premixing performance of the standby fuel and air, and the jet depth of the standby fuel can be adjusted, thereby controlling the position, shape, and size of the standby flame, reducing NOx generation, and suppressing backfire.

[0036] By adjusting the axial length of the duty fuel injector and the central blunt body, the overall axial distribution of the flame can be controlled, thereby improving flame stability.

[0037] By adjusting the outer diameter and fillet of the central blunt body, the outlet flow rate of the main nozzle can be controlled, thereby achieving the goals of constraining the position and shape of the flame, suppressing backfire, and preventing blowout.

[0038] By adjusting the air volume, outlet cross-section shape, number of holes, orifice diameter, and incident angle of the cooling air at the center of the fuel injector, effective cooling can be achieved at the nozzle tip to prevent overheating and backfire.

[0039] The foregoing basic examples and their further alternative examples of the present invention can be freely combined to form multiple embodiments, all of which are embodiments that can be adopted and claimed by the present invention. In the present invention, each alternative example can be arbitrarily combined with any other basic example and alternative example.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for using an ultra-low emission duty nozzle for a gas turbine burner, wherein the ultra-low emission duty nozzle for the gas turbine burner comprises a central blunt body (1) and a duty fuel injection rod (2), characterized in that: The central blunt body (1) includes a blunt body neck (4), and the duty fuel injector (2) includes an inner ring (6) and an outer ring (7). The outer ring (7) is fitted inside the blunt body neck (4), and the inner ring (6) is fitted inside the outer ring (7). There is a tail end sealing part (8) between the inner ring (6) and the outer ring (7). The tail end of the outer ring (7) is provided with several duty fuel injection holes (9). A cooling airflow channel (10) is formed inside the inner ring (6). A duty fuel channel (11) is formed between the inner ring (6) and the outer ring (7). A fuel mixing airflow channel (12) is formed between the outer ring (7) and the blunt body neck (4). The method of use is as follows: by adjusting the diameter, number and incident angle of the duty fuel nozzle, as well as the flow rate of the duty fuel mixed air, the size of the gap between the central blunt body and the duty fuel nozzle rod, the premixing performance of the duty fuel and air and the jet depth of the duty fuel are adjusted, thereby controlling the position, shape and size of the duty flame, reducing NOx generation and suppressing backfire; By adjusting the axial length of the duty fuel injector and the central blunt body, the overall axial distribution of the flame is controlled, thereby improving flame stability. By adjusting the outer diameter and fillet of the central blunt body, the outlet flow rate of the main nozzle is controlled, thereby achieving the goals of constraining the position and shape of the flame, suppressing backfire, and preventing blowout. By adjusting the air volume, outlet cross-section shape, number of holes, orifice diameter, and incident angle of the cooling air at the center of the fuel injector, effective cooling is achieved at the nozzle tip to prevent overheating and backfire.

2. The method of using the ultra-low emission duty nozzle of the gas turbine burner according to claim 1, characterized in that: The central blunt body (1) further includes a blunt body end ring (3) and an arc-shaped transition part (18). The center of the blunt body end ring (3) is connected to the head end of the blunt body neck (4) through the arc-shaped transition part (18). The duty fuel injector (2) further includes an injector end ring (15). The center of the injector end ring (15) is connected to the head end of the injector outer ring (7).

3. The method of using the ultra-low emission duty nozzle of the gas turbine burner according to claim 1, characterized in that: The blunt neck (4), the inner ring (6) of the spray bar, and the outer ring (7) of the spray bar are all cylindrical structures, and the three are arranged along the same axis.

4. The method of using the ultra-low emission duty nozzle of the gas turbine burner according to claim 1, characterized in that: The blunt neck (4) is also provided with a blunt tail cone ring (5) at its tail end.

5. The method of using the ultra-low emission duty nozzle of the gas turbine burner according to claim 1, characterized in that: The tail end faces of the inner ring (6) and outer ring (7) of the spray bar are flush with the tail end platform of the blunt body neck (4).

6. The method of using the ultra-low emission duty nozzle of the gas turbine burner according to claim 1, characterized in that: The duty fuel injection port (9) is arranged at an angle from the front inside to the rear outside.

7. The method of using the ultra-low emission duty nozzle of the gas turbine burner according to claim 2, characterized in that: The blunt end ring (3) is connected to the burner head (13) by bolts (14), and the spray rod end ring (15) is connected to the burner head (13) by bolts (14).

8. The method of using the ultra-low emission duty nozzle of the gas turbine burner according to claim 2 or 7, characterized in that: The blunt end ring (3) is provided with a fuel mixing airflow inlet (16) and a radial channel (17). The fuel mixing airflow inlet (16) penetrates the inner and outer surfaces of the blunt end ring (3). The fuel mixing airflow inlet (16) is connected to the radial channel (17). The radial channel (17) is located between the blunt end ring (3) and the burner head (13). The radial channel (17) is connected to the fuel mixing airflow channel (12).

9. The method of using the ultra-low emission duty nozzle of the gas turbine burner according to claim 1, characterized in that: The cooling airflow channel (10) is equipped with an ignition hydrant and a flame detector.

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