A low-swirl tip structure for a natural gas-hydrogen blended gas turbine combustor

Abstract

The application belongs to the technical field of combustion chambers, in particular to a low-swirl head structure of a natural gas hydrogen-blended gas turbine combustion chamber, which comprises a gas turbine body, a combustion chamber is fixedly installed at the middle part of the gas turbine body, a cylindrical combustion pipe is fixedly connected inside the combustion chamber, a turbulence mechanism is fixedly installed inside the cylindrical combustion pipe, and a swirl mechanism is fixedly connected to the upper surface of the cylindrical combustion pipe; the above-mentioned structure is matched with the set turbulence mechanism, the turbulence mechanism can significantly improve the combustion performance, stability and emission characteristics by increasing the turbulence mechanism in the low-swirl head structure of the combustion chamber of the natural gas hydrogen-blended gas turbine, the turbulence mechanism can disturb the laminar state of the airflow by introducing vortex or changing the airflow direction, enhance the mixing of natural gas and hydrogen with air, and improve the uniformity of combustion, the introduction of turbulence can effectively distribute the heat uniformly, reduce the formation of hot spots, and facilitate the improvement of the durability of the combustion chamber.

Description

Technical Field

[0001] This invention belongs to the field of combustion chamber technology, specifically a low-swirl head structure for a natural gas hydrogen-blended gas turbine combustion chamber. Background Technology

[0002] A gas turbine is a thermal engine that uses gas as its working medium and is widely used in power generation and aviation. It generates high-temperature, high-pressure gas by burning fuel, which drives a turbine to rotate, thereby driving a generator or other mechanical equipment. Natural gas blending with hydrogen refers to mixing hydrogen and natural gas in a certain proportion to form a mixed gas that can be used for combustion or as an energy carrier. This practice is of great significance in promoting clean energy, reducing carbon emissions, and realizing the transformation of the energy system. The low-swirl head structure of the combustion chamber of a natural gas blended gas turbine is a key component designed to optimize the combustion of fuel (natural gas and hydrogen mixture). This design is crucial for improving combustion efficiency, reducing emissions, and ensuring combustion stability.

[0003] A Chinese invention patent, CN 107543202 B, discloses a single-swirl head structure for a low-emission combustion chamber of a gas turbine. The key technical points are: it includes mixing central swirling air with central natural gas, and mixing outer wall non-swirling air with outer wall natural gas. Then, the swirling air, non-swirling air, central natural gas, and outer wall natural gas are further mixed in a natural gas-air mixing chamber, which improves the uniformity of the natural gas-air mixture, avoids hot spots, and effectively reduces the generation of nitrogen oxides. The combined central swirling and outer wall non-swirling air supply method reduces the swirling intensity of the head outlet airflow, lowering the risk of oscillating combustion. The combination of central natural gas and outer wall natural gas improves the NOx-CO ratio and helps stabilize the flame. The head outlet convergence section increases the velocity of the natural gas-air mixed airflow, effectively preventing backfire. Tangential air inlet holes on the outer wall of the swirler reduce the risk of spontaneous combustion inside the head structure.

[0004] However, the above technologies often have the following drawbacks: When gas is released from the low-swirl head structure of the combustion chamber, the low-swirl design may result in less uniform mixing of fuel and air compared to the high-swirl design, thus affecting the completeness of combustion. This leads to uneven heat load distribution, which may cause excessively high temperatures in some areas, resulting in local overheating and subsequently causing softening or embrittlement of materials, increasing the risk of structural failure. In addition, the uneven heat distribution of the low-swirl head may cause fuel to fail to burn completely in some areas, increasing the emission of unburned fuel and reducing combustion efficiency.

[0005] Therefore, the present invention provides a low-swirl head structure for the combustion chamber of a natural gas hydrogen-blended gas turbine. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0007] The technical solution adopted by the present invention to solve its technical problem is as follows: The present invention provides a low swirl head structure for a natural gas hydrogen-blended gas turbine combustion chamber, comprising a gas turbine body, a combustion chamber fixedly installed in the middle of the gas turbine body, a cylindrical combustion tube fixedly connected inside the combustion chamber, a turbulence-inducing mechanism fixedly installed inside the cylindrical combustion tube, a swirl mechanism fixedly connected to the upper surface of the cylindrical combustion tube, a connecting block fixedly attached to the bottom end face of the cylindrical combustion tube, and a drain pipe fixedly connected to the upper surface of the connecting block;

[0008] The turbulence-disrupting mechanism includes a turbulence-disrupting net, with connecting rods fixedly connected to both sides of the turbulence-disrupting net. One end of each connecting rod is fixedly connected to the inner wall of the cylindrical combustion tube, and turbulence-disrupting holes are formed on the surface of the turbulence-disrupting net.

[0009] As a preferred technical solution of this application, the swirl mechanism includes a connecting plate, the bottom of which is fixedly connected to the upper surface of the cylindrical combustion tube, swirl blades are fixedly connected inside the connecting plate, flow plates are fixedly connected at intervals to the inner sidewalls of the swirl blades, and air inlet grooves are formed on the surface of the flow plates.

[0010] As a preferred technical solution of this application, a snap-fit ​​ring is fixedly connected to the outer surface of the cylindrical combustion tube, and a cooling tube is fixedly connected to the middle of the snap-fit ​​ring, with coolant disposed inside the cooling tube.

[0011] As a preferred technical solution of this application, a support rod is fixedly connected to the middle of the interior of the turbulence net, and a vortex conduit is fixedly connected to the interior of the turbulence net, the vortex conduit being spiral in shape.

[0012] As a preferred technical solution of this application, a tapered tube is fixedly connected to the upper surface of the connecting plate, and a gas fuel outlet groove is opened on the surface of the tapered tube.

[0013] As a preferred technical solution of this application, a gas collecting nozzle is fixedly connected to the upper surface of the tapered tube, and an A gas fuel injection hole is opened on the outer surface of the gas collecting nozzle, and a B gas fuel injection hole is opened on the side of the outer surface of the gas collecting nozzle near the A gas fuel injection hole.

[0014] As a preferred technical solution of this application, an air outlet nozzle is fixedly connected to the upper surface of the air collecting nozzle, and a head mixed gas outlet is opened on the upper surface of the air outlet nozzle. A baffle plate is fixedly connected inside the head mixed gas outlet.

[0015] As a preferred technical solution of this application, the surface of the cylindrical combustion tube is provided with dispersion holes, and the dispersion holes are arranged side by side.

[0016] The beneficial effects of this invention are as follows:

[0017] 1. The present invention discloses a low-swirl head structure for a natural gas hydrogen-blended gas turbine combustion chamber. By adding a turbulence-inducing mechanism to the low-swirl head structure of the combustion chamber of the natural gas hydrogen-blended gas turbine, the combustion performance, stability, and emission characteristics can be significantly improved. The turbulence-inducing mechanism can disrupt the laminar flow state of the airflow by introducing eddies or changing the airflow direction, thereby enhancing the mixing of natural gas and hydrogen with air and improving the uniformity of combustion. The introduction of turbulence can effectively and uniformly distribute heat, reduce the formation of hot spots, and facilitate the improvement of the durability of the combustion chamber.

[0018] 2. The low-swirl head structure of the combustion chamber of a natural gas-hydrogen blended gas turbine described in this invention, through the setting of a swirl mechanism, forms a rotating airflow, which allows the mixture of natural gas and hydrogen to have more full contact with air, promotes the uniformity of mixing, ensures that the fuel and oxygen react fully, and the swirl mechanism can maintain the stability of the flame, reduce the risk of flameout caused by changes in fuel composition. Especially under low load or instantaneous load fluctuations, the swirling airflow achieves a more uniform heat distribution, avoids local overheating or cooling, reduces the thermal shock to the combustion chamber wall, and extends the service life of the materials;

[0019] 3. The low-swirl head structure of the combustion chamber of a natural gas hydrogen-blended gas turbine, as described in this invention, enhances the guiding effect of airflow by adding a guide pipe to the combustion chamber of the natural gas hydrogen-blended gas turbine. This results in a more uniform mixture of air and hydrogen-blended fuel, avoids local airflow deviations, and promotes more stable combustion. By rationally arranging the guide pipe, internal airflow turbulence and vortex formation can be reduced, ensuring a more continuous flow of gas within the combustion chamber and improving overall combustion efficiency. Attached Figure Description

[0020] The invention will now be further described with reference to the accompanying drawings.

[0021] Figure 1 A schematic diagram of a low-swirl head structure for the combustion chamber of a natural gas hydrogen-blended gas turbine.

[0022] Figure 2 This is a schematic diagram of the gas turbine body in a low-swirl head structure of a natural gas hydrogen-blended gas turbine combustion chamber.

[0023] Figure 3 This is a schematic diagram of the turbulence mesh in the low swirl head structure of a natural gas hydrogen-blended gas turbine combustor.

[0024] Figure 4 This is a schematic diagram of the swirl blades in a low-swirl head structure of a natural gas hydrogen-blended gas turbine combustion chamber.

[0025] Figure 5 This is a schematic diagram of the cylindrical combustion tube in a low-swirl head structure of a natural gas hydrogen-blended gas turbine combustion chamber.

[0026] Figure 6 This is a schematic diagram of the gas collecting nozzle in the low swirl head structure of the combustion chamber of a natural gas hydrogen-blended gas turbine.

[0027] In the diagram: 1. Gas turbine body; 2. Combustion chamber; 3. Cylindrical combustion tube; 4. Connecting block; 5. Drainage pipe; 6. Baffle net; 7. Connecting rod; 8. Baffle hole; 9. Connecting disc; 10. Swirl blade; 11. Flow plate; 12. Snap ring; 13. Cooling pipe; 14. Support rod; 15. Swirl duct; 16. Gradually converging conical tube; 17. Gas fuel outlet trough; 18. Gas collecting nozzle; 19. Gas fuel nozzle A; 20. Gas fuel nozzle B; 21. Gas outlet nozzle; 22. Barrier plate; 23. Dispersion hole. Detailed Implementation

[0028] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0029] Reference Figure 1 - Figure 6 This invention provides two technical solutions:

[0030] Example 1:

[0031] A low-swirl head structure for a natural gas hydrogen-blended gas turbine combustion chamber includes a gas turbine body 1, a combustion chamber 2 fixedly installed in the middle of the gas turbine body 1, a cylindrical combustion tube 3 fixedly connected inside the combustion chamber 2, a turbulence-inducing mechanism fixedly installed inside the cylindrical combustion tube 3, a swirl mechanism fixedly connected to the upper surface of the cylindrical combustion tube 3, a connecting block 4 fixedly attached to the bottom end face of the cylindrical combustion tube 3, and a drain pipe 5 fixedly connected to the upper surface of the connecting block 4.

[0032] The turbulence mechanism includes a turbulence net 6, with connecting rods 7 fixedly connected to both sides of the turbulence net 6. One end of the connecting rod 7 is fixedly connected to the inner wall of the cylindrical combustion tube 3. Turbulence holes 8 are opened on the surface of the turbulence net 6. Adding a turbulence mechanism to the low swirl head structure of the combustion chamber of a natural gas-blended gas turbine can significantly improve combustion performance, stability, and emission characteristics. The turbulence net 6 in the turbulence mechanism can disrupt the laminar flow state of the airflow by introducing eddies or changing the airflow direction, thereby enhancing the mixing of natural gas and hydrogen with air and improving the uniformity of combustion. The gas flows out from the turbulence holes 8 on the surface of the turbulence net 6. The introduction of turbulence can effectively and evenly distribute heat, reduce the formation of hot spots, and facilitate the improvement of the durability of the combustion chamber 2.

[0033] Example 2:

[0034] Based on Embodiment 1: The swirl mechanism includes a connecting plate 9, the bottom of which is fixedly connected to the upper surface of the cylindrical combustion tube 3. Swirl blades 10 are fixedly connected inside the connecting plate 9. Flow plates 11 are fixedly connected at intervals to the inner sidewall of the swirl blades 10. An air inlet groove is provided on the surface of the flow plate 11.

[0035] A snap-fit ​​ring 12 is fixedly connected to the outer surface of the cylindrical combustion tube 3. A cooling tube 13 is fixedly connected to the middle of the snap-fit ​​ring 12. Cooling fluid is provided inside the cooling tube 13. The cooling tube 13 can reduce the formation of local high temperature areas, reduce the thermal shock to the combustion chamber 2 material, and extend its service life. The cooling tube 13 can help maintain the stability of the combustion process. For natural gas mixed with hydrogen, it reduces the risk of flameout and enables the gas turbine body 1 to operate stably under various load conditions.

[0036] A support rod 14 is fixedly connected to the center of the inside of the turbulence net 6. A swirl guide tube 15 is fixedly connected inside the turbulence net 6. The swirl guide tube 15 is spiral in shape. The gas is dispersed into the turbulence net 6 and guided along the swirl guide tube 15 into the cylindrical combustion tube 3. The spiral guide tube can effectively guide the gas flow, promote the uniform mixing of natural gas and hydrogen, reduce the dead zone and blind zone of gas in the combustion chamber 2, and improve the mixing effect.

[0037] A tapered tube 16 is fixedly connected to the upper surface of the connecting plate 9, and a gas fuel outlet groove 17 is opened on the surface of the tapered tube 16.

[0038] A gas collecting nozzle 18 is fixedly connected to the upper surface of the tapered tube 16. The outer surface of the gas collecting nozzle 18 is provided with an A gas fuel injection hole 19, and the outer surface of the gas collecting nozzle 18 is provided with a B gas fuel injection hole 20 on the side near the A gas fuel injection hole 19. The uniformly distributed gas is ejected from the gas fuel outlet groove 17 of the tapered tube 16, or it can be dispersed from the dispersion hole 23, which can disperse part of the gas and play a role in dispersing and guiding the flow. The other part of the gas is ejected from the A gas fuel injection hole 19 and the B gas fuel injection hole 20 at the gas collecting nozzle 18, which facilitates the dispersion of the gas.

[0039] An outlet nozzle 21 is fixedly connected to the upper surface of the gas collecting nozzle 18. The upper surface of the outlet nozzle 21 has a head mixed gas outlet. A baffle plate 22 is fixedly connected inside the head mixed gas outlet. Gas that is not completely dispersed is dispersed from the outlet nozzle 21. The baffle plate 22 is used to block and disperse the gas, so that the gas is more evenly discharged.

[0040] The surface of the cylindrical combustion tube 3 is provided with dispersion holes 23. Several dispersion holes 23 are arranged side by side. When the gas in the combustion chamber 2 flows into the cylindrical combustion tube 3, it can be dispersed from the dispersion holes 23 in the cylindrical combustion tube 3, thus achieving the effect of dispersion and outflow.

[0041] Working Principle: When the gas turbine body 1 is working, the gas in the combustion chamber 2 flows through the cylindrical combustion tube 3 and through the turbulence net 6. The turbulence net 6 can introduce vortices or change the airflow direction to disrupt the laminar flow state, enhance the mixing of natural gas and hydrogen with air, and improve the uniformity of combustion. Subsequently, the gas is dispersed into the turbulence net 6 and guided along the swirl duct 15, flowing through the cylindrical combustion tube 3 and from the swirl blades 10, forming a rotating airflow. The swirl mechanism, by forming a rotating airflow, ensures that the mixture of natural gas and hydrogen comes into more complete contact with air, promoting the uniformity of mixing and ensuring the fuel and air are properly mixed. After the oxygen has fully reacted, the homogenized gas is ejected from the gas fuel outlet trough 17 of the converging conical tube 16, or it can be dispersed from the dispersion hole 23. This disperses some of the gas, preventing it from flowing from a single outlet. Gas dispersing from a single outlet may lead to uneven airflow distribution in the combustion chamber 2, potentially causing localized overheating or cooling, reducing combustion efficiency. Especially in the case of hydrogen blending, gas dispersing from a single outlet may form a combustible mixture, increasing the risk of explosion and fire. Uneven combustion may also lead to localized high temperatures, thereby increasing the production of harmful substances such as NOx and affecting environmental compliance. Part of the gas is ejected from the A gas fuel injection hole 19 and B gas fuel injection hole 20 at the gas collecting nozzle 18, facilitating gas dispersion. Incompletely dispersed gas exits from the outlet nozzle 21, where the blocking plate 22 further disperses and obstructs the gas, ensuring more uniform gas distribution. During combustion, the cooling pipe 13 lowers the temperature inside the combustion chamber 2. The cooling pipe 13 effectively absorbs and removes heat generated during combustion, thus reducing the overall temperature inside the combustion chamber 2, protecting equipment and materials. The cooling pipe 13 also reduces the formation of localized high-temperature areas, minimizing thermal shock to the combustion chamber 2 materials and extending their service life. The cooling pipe 13 helps maintain the stability of the combustion process, reducing the risk of flameout for natural gas blended with hydrogen, and enabling the gas turbine body 1 to operate stably under various load conditions. Subsequently, the gas in the combustion chamber 2 that has not entered the cylindrical combustion pipe 3 is guided by the diversion pipe 5. The design of the diversion pipe 5 can enhance the guiding effect of the airflow, making the mixing of air and hydrogen-blended fuel more uniform, avoiding local airflow deviation, and thus promoting more stable combustion. By reasonably arranging the diversion pipe 5, the internal turbulence and vortex formation of the airflow can be reduced, ensuring that the flow of gas in the combustion chamber 2 is more continuous and improving the overall combustion efficiency.

[0042] The terms "front," "back," "left," "right," "top," and "bottom" all refer to the figures in the accompanying drawings. Figure 1 Based on the perspective of the observer, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0043] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0044] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low-swirl head structure for the combustion chamber of a natural gas hydrogen-blended gas turbine, characterized in that: The device includes a gas turbine body (1), a combustion chamber (2) is fixedly installed in the middle of the gas turbine body (1), a cylindrical combustion tube (3) is fixedly connected inside the combustion chamber (2), a turbulence mechanism is fixedly installed inside the cylindrical combustion tube (3), a swirl mechanism is fixedly connected to the upper surface of the cylindrical combustion tube (3), a connecting block (4) is fixedly attached to the bottom end face of the cylindrical combustion tube (3), and a diversion pipe (5) is fixedly connected to the upper surface of the connecting block (4). The turbulence mechanism includes a turbulence mesh (6), and connecting rods (7) are fixedly connected to both sides of the turbulence mesh (6). One end of the connecting rod (7) is fixedly connected to the inner wall of the cylindrical combustion tube (3), and turbulence holes (8) are opened on the surface of the turbulence mesh (6). A support rod (14) is fixedly connected to the center of the inside of the turbulence net (6), and a vortex conduit (15) is fixedly connected inside the inside of the turbulence net (6). The vortex conduit (15) is spiral in shape.

2. The low-swirl head structure of the combustion chamber of a natural gas hydrogen-blended gas turbine according to claim 1, characterized in that: The swirling mechanism includes a connecting disk (9), the bottom of which is fixedly connected to the upper surface of the cylindrical combustion tube (3). Swirling blades (10) are fixedly connected inside the connecting disk (9). Flow plates (11) are fixedly connected at intervals to the inner sidewall of the swirling blades (10). Inlet grooves are provided on the surface of the flow plates (11).

3. The low-swirl head structure of the combustion chamber of a natural gas hydrogen-blended gas turbine according to claim 1, characterized in that: A snap ring (12) is fixedly connected to the outer surface of the cylindrical combustion tube (3), and a cooling tube (13) is fixedly connected to the middle of the snap ring (12). Cooling liquid is provided inside the cooling tube (13).

4. The low-swirl head structure of the combustion chamber of a natural gas hydrogen-blended gas turbine according to claim 2, characterized in that: A tapered tube (16) is fixedly connected to the upper surface of the connecting plate (9), and a gas fuel outlet groove (17) is opened on the surface of the tapered tube (16).

5. The low-swirl head structure of the combustion chamber of a natural gas hydrogen-blended gas turbine according to claim 4, characterized in that: The upper surface of the tapered tube (16) is fixedly connected to a gas collecting nozzle (18). The outer surface of the gas collecting nozzle (18) is provided with an A gas fuel injection hole (19), and the outer surface of the gas collecting nozzle (18) is provided with a B gas fuel injection hole (20) on the side near the A gas fuel injection hole (19).

6. The low-swirl head structure of the combustion chamber of a natural gas hydrogen-blended gas turbine according to claim 5, characterized in that: The upper surface of the gas collecting nozzle (18) is fixedly connected to the gas outlet nozzle (21), and the upper surface of the gas outlet nozzle (21) is provided with a head mixed gas outlet. The interior of the head mixed gas outlet is fixedly connected to a baffle plate (22).

7. The low-swirl head structure of the combustion chamber of a natural gas hydrogen-blended gas turbine according to claim 1, characterized in that: The surface of the cylindrical combustion tube (3) is provided with dispersion holes (23), and a number of dispersion holes (23) are arranged side by side.

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