A premixed low-emission combustion chamber for a pure hydrogen gas turbine

Abstract

This invention relates to the field of low-emission combustor application technology for gas turbines, and particularly to a premixed low-emission combustor control unit for pure hydrogen gas turbines. It addresses the problem of extremely high NOx emission control due to the high temperature of diffusion combustion flames. The unit includes an igniter, a flange, a control unit head, a fuel annular cavity, and a control unit deflector. The bottom end of the fuel annular cavity is welded to the control unit head. The igniter passes through the top of the fuel annular cavity and is flush with the control unit head. The flange is connected to the fuel annular cavity. The control unit deflector is fixed to the outer annular wall of the control unit head, and the deflector and the outer shell of the fuel annular cavity form an air inlet. This invention employs adjustable equivalence ratio premixed combustion technology. The control unit supports the flame, providing a sufficiently long mixing distance without increasing the premixing length of the control unit head. The strong turbulence within the control unit's premixing section enables rapid and uniform mixing of the two components. Fuel is uniformly supplied to the premixing section through the fuel annular cavity, contributing to improved premixing efficiency.

Description

Technical Field

[0001] This invention relates to the field of low-emission combustion chamber application technology for gas turbines, and more particularly to a premixed low-emission combustion chamber for pure hydrogen gas turbines. Background Technology

[0002] Hydrogen fuel exhibits significantly different combustion characteristics compared to conventional fossil fuels. For instance, at ambient temperature and pressure, the adiabatic flame propagation speed of hydrogen fuel is 10 times that of methane, and its adiabatic flame temperature is approximately 150K higher. Low-emission combustors typically employ dry low-emission technology, where air and fuel are premixed to ensure low stoichiometric combustion. However, this combustion occurs at the lean flameout limit. Furthermore, the head of the mainstream hydrogen-burning combustor uses a micro-mixing structure, which often leads to interference between the small flames generated, resulting in combustion instability issues during hydrogen fuel combustion. A well-designed combustion control system can address these problems. Conventional gas turbine combustors typically employ diffusion combustion. While this method avoids backfire, the extremely high flame temperature makes NOx emission control extremely difficult, hindering the achievement of low-emission requirements for gas turbines.

[0003] Therefore, there is an urgent need to propose a premixed low-emission combustion chamber shifter for pure hydrogen gas turbines to solve the above-mentioned technical problems. Summary of the Invention

[0004] The purpose of this invention is to address the problem that commonly used diffusion combustion technologies result in extremely high flame temperatures, making NOx emission control extremely difficult and hindering the achievement of low emission requirements for gas turbines. A brief overview of this invention is provided below to offer a basic understanding of certain aspects of the invention. It should be understood that this overview is not an exhaustive summary of the invention. It is not intended to identify key or essential parts of the invention, nor is it intended to limit the scope of the invention.

[0005] The technical solution of this invention:

[0006] A premixed low-emission combustor for a pure hydrogen gas turbine includes an igniter, a connecting flange, a combustor head, a fuel annular cavity, and a combustor deflector. One end of the fuel annular cavity is welded to the combustor head, and the igniter passes through the fuel annular cavity from the other end, with one end of the igniter engaging with the combustor head. The connecting flange is connected to the fuel annular cavity, and the combustor deflector is fixed to the outer annular wall of the combustor head. An air inlet is formed between the inner wall of the deflector and the outer shell of the fuel annular cavity.

[0007] Preferably, the duty officer's head has an axial through hole, four circumferentially equidistant air holes are opened on the side wall of the duty officer's head base, 50 cooling holes are evenly opened in the middle of the outer ring wall of the duty officer's head, 14 premixed gas injection holes are opened on the other side of the duty officer's head, the through hole on the other side of the duty officer's head is a mounting hole, the diameter of the mounting hole is 2mm larger than the diameter of the igniter, and the diameter of the premixed gas injection hole is 3mm.

[0008] Preferably, the igniter and the outer wall of the duty officer's head form a cooling airflow channel for the duty officer.

[0009] Preferably, a fuel port is provided on the top side wall of the fuel ring cavity, and a flange sealing gasket groove is also provided in the fuel ring cavity. The flange gasket is placed in the flange sealing gasket groove. An installation thread is provided below the igniter sealing gasket groove. The connecting flange is connected to the fuel ring cavity through the installation thread. A fuel annular flow channel is provided inside the fuel ring cavity. Multiple fuel dispersion tubes are located at the bottom of the fuel ring cavity. The fuel annular flow channel is connected to the fuel dispersion tubes. The fuel dispersion tubes are provided with nozzles.

[0010] Preferably, the igniter has an igniter sealing gasket groove, the igniter sealing gasket is placed in the igniter sealing gasket groove, and an external thread is provided below the igniter sealing gasket groove. The igniter is connected to the fuel ring cavity through the external thread. The igniter and the fuel ring cavity are coaxially arranged. The bottom end of the igniter is the ignition head, which is flush with the mounting hole. The ignition head and the mounting hole form a cooling ring cavity.

[0011] Preferably, the nozzle is a pipe wall guide angle nozzle, the area between the nozzle and the premixed gas nozzle is a premixing section, the nozzle and the premixing section are axially aligned, the other side of the duty head is frustum-shaped, and the side wall of the duty head is machined with premixed gas nozzles.

[0012] Preferred: The premixing section of the duty class adopts a micro-mixing structure, and the pore size of the premixing section is 3mm.

[0013] The present invention has the following beneficial effects:

[0014] This invention employs adjustable equivalence ratio premixed combustion technology. On the one hand, the flame is supported by the flame, providing a sufficiently long mixing distance without increasing the premixing length of the flame head. On the other hand, the turbulence within the premixing section of the flame is strong, and the intense momentum exchange between fuel and air enables rapid and uniform mixing of the two. The fuel is evenly distributed and supplied to the premixing section through the fuel annular cavity, which helps to improve the premixing effect.

[0015] This invention employs a weak swirling structure, which does not use swirling blades, ensuring a high flow velocity within the premixing section and avoiding backfire problems caused by excessively fast hydrogen fuel flame propagation. Attached Figure Description

[0016] Figure 1This is a schematic diagram of the structure of a premixed low-emission combustion chamber for a pure hydrogen gas turbine.

[0017] Figure 2 This is an exploded view of a premixed, low-emission combustion chamber for a pure hydrogen gas turbine.

[0018] Figure 3 This is a cross-sectional view of a premixed low-emission combustion chamber in a pure hydrogen gas turbine.

[0019] Figure 4 This is a schematic diagram of the head structure of a premixed low-emission combustion chamber for a pure hydrogen gas turbine.

[0020] Figure 5 This is a schematic diagram of the fuel annular cavity structure for a premixed low-emission combustion chamber in a pure hydrogen gas turbine.

[0021] Figure 6 This is a schematic diagram of the igniter structure for a premixed low-emission combustion chamber in a pure hydrogen gas turbine.

[0022] In the diagram: 1-Igniter, 2-Igniter sealing gasket, 3-Connecting flange, 4-Operator head, 5-Flange gasket, 6-Fuel annular cavity, 7-Operator flow guide, 8-Air inlet, 9-Operator cooling airflow channel, 10-Cooling annular cavity, 1.1-Igniter sealing gasket groove, 1.2-External thread, 1.3-Igniter head, 4.1-Air hole, 4.2-Cooling hole, 4.3-Mounting hole, 4.4-Premix section, 4.5-Premixed gas nozzle, 6.1-Fuel port, 6.2-Flange sealing gasket groove, 6.3-Mounting thread, 6.4-Fuel annular flow channel, 6.5-Fuel dispersion tube, 6.6-Nozzle. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0024] Specific implementation method one: Combining Figures 1-6 This embodiment describes a premixed low-emission combustor for a pure hydrogen gas turbine, comprising an igniter 1, a connecting flange 3, a combustor head 4, a fuel annular cavity 6, and a combustor deflector 7. One end of the fuel annular cavity 6 is welded to the combustor head 4, and the igniter 1 passes through the fuel annular cavity 6 from the other end, with one end of the igniter 1 engaging with the combustor head 4. The connecting flange 3 is connected to the fuel annular cavity 6, and the combustor deflector 7 is fixed to the outer annular wall of the combustor head 4. An air inlet 8 is formed between the inner wall of the deflector 7 and the outer shell of the fuel annular cavity 6.

[0025] Specific Implementation Method Two: Combining Figures 1-6 This embodiment describes a premixed low-emission combustion chamber for a pure hydrogen gas turbine. The combustion chamber head 4 has an axial through hole. Four circumferentially equidistant air holes 4.1 are opened on the side wall of the base of the combustion chamber head 4. Fifty cooling holes 4.2 are evenly opened in the middle of the outer ring wall of the combustion chamber head 4. Fourteen premixed gas injection holes 4.5 are opened on the other side of the combustion chamber head 4. The through hole on the other side of the combustion chamber head 4 is a mounting hole 4.3. The diameter of the mounting hole 4.3 is 2mm larger than the diameter of the igniter 1. The diameter of the premixed gas injection hole 4.5 is 3mm.

[0026] Specific implementation method three: Combining Figures 1-6 This embodiment describes a premixed low-emission combustion chamber for a pure hydrogen gas turbine, wherein the igniter 1 and the outer wall of the combustion chamber head 4 form a cooling airflow channel 9.

[0027] Specific implementation method four: Combination Figures 1-6 This embodiment describes a premixed low-emission combustion chamber for a pure hydrogen gas turbine. A fuel inlet 6.1 is located on the top sidewall of a fuel annular cavity 6. The fuel annular cavity 6 also has a flange sealing gasket groove 6.2, in which a flange gasket 5 is placed. An installation thread 6.3 is located below the gasket groove 1.1, and a connecting flange 3 is connected to the fuel annular cavity 6 via the installation thread 6.3. An annular fuel flow channel 6.4 is located inside the fuel annular cavity 6. Multiple fuel dispersion tubes 6.5 are located at the bottom of the fuel annular cavity 6, communicating with the annular fuel flow channel 6.4. Each fuel dispersion tube 6.5 has a nozzle 6.6.

[0028] Specific Implementation Method Five: Combining Figures 1-6 This embodiment describes a premixed low-emission combustion chamber for a pure hydrogen gas turbine. The igniter 1 has an igniter sealing gasket groove 1.1, and an igniter sealing gasket 2 is placed inside the igniter sealing gasket groove 1.1. An external thread 1.2 is provided below the igniter sealing gasket groove 1.1. The igniter 1 is connected to the fuel annular cavity 6 via the external thread 1.2. The igniter 1 and the fuel annular cavity 6 are coaxially arranged. The bottom end of the igniter 1 is an ignition head 1.3, which is flush with the mounting hole 4.3. A cooling annular cavity 10 is formed between the igniter head 1.3 and the mounting hole 4.3.

[0029] Specific Implementation Method Six: Combination Figures 1-6This embodiment describes a premixed low-emission combustion chamber for a pure hydrogen gas turbine. The nozzle 6.6 is a pipe-wall-guided angled nozzle. A premixing section 4.4 is located between the nozzle 6.6 and the premixed gas nozzle 4.5. The nozzle 6.6 and the premixing section 4.4 are coaxially aligned. The other side of the combustion chamber head 4 is frustum-shaped, and the sidewall of the combustion chamber head 4 is machined with premixed gas nozzles 4.5.

[0030] Specific implementation method seven: Combining Figures 1-6 This embodiment describes a premixed low-emission combustion chamber for a pure hydrogen gas turbine. The premixing section 4.4 of the premixing section adopts a micro-mixing structure, and the orifice diameter of the premixing section is 3mm.

[0031] Air first enters the duty room through air inlet 8. This air is divided into premixed air and cooling air. The cooling hole 4.2 and the inside of the guide shroud 7 are matched. When the cooling air of the duty room passes through the cooling hole 4.2, a ring-shaped cooling airflow is formed around the duty room to ensure that the duty room is not burned at high temperatures. The head of the duty room is not on the same plane as the main combustion stage panel. Its frustum part extends completely into the main combustion zone, which can prevent the premixed air with a relatively high equivalent from being sprayed onto the head panel of the main combustion stage and burning the main combustion stage.

[0032] Premixed air and igniter cooling air enter through the duty air hole 4.1. A small portion of the air enters the igniter cooling ring cavity 10 between the igniter 1 and the igniter mounting hole 4.3 to cool the igniter. Most of the air enters the premixing section and premixes with the fuel from the fuel dispersion pipe 6.5 in the premixing section 4.4. Finally, it is injected into the main combustion zone from the premixer nozzle 4.5.

[0033] Fuel flows into the fuel annular flow channel 64 through the fuel port 6.1 for buffering, forming a uniformly distributed annular airflow to ensure that the intake volume of the fuel dispersion tube 6.5 is the same. The nozzle 6.6 extends slightly into the premixing section, and the fuel enters the premixing section from the fuel nozzle 6.6 to mix with the premixed air to achieve the purpose of low emissions.

[0034] The fuel ring cavity 6 is threaded onto the connecting flange 3. A flange gasket 5 is placed in the sealing gasket groove 6.2 to prevent hydrogen fuel leakage. The connecting flange is fixed to the combustion chamber casing.

[0035] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be permuted and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutation and combination. Therefore, the present invention will not describe the technical solutions after permutation and combination one by one, but it should be understood that the technical solutions after permutation and combination have been disclosed by the present invention.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A premixed low-emission combustion chamber control unit for a pure hydrogen gas turbine, characterized in that: It includes an igniter (1), a connecting flange (3), a duty head (4), a fuel ring cavity (6), and a duty head shroud (7). One end of the fuel ring cavity (6) is welded to the duty head (4). The igniter (1) passes through the fuel ring cavity (6) from the other end. One end of the igniter (1) is fitted with the duty head (4). The connecting flange (3) is connected to the fuel ring cavity (6). The duty head shroud (7) is fixed on the outer ring wall of the duty head (4). An air inlet (8) is formed between the inner wall of the shroud (7) and the outer shell of the fuel ring cavity (6).

2. The premixed low-emission combustion chamber control system for a pure hydrogen gas turbine according to claim 1, characterized in that: The duty head (4) has an axial through hole. Four air holes (4.1) are circumferentially equidistantly arranged on the side wall of the base of the duty head (4). Cooling holes (4.2) are uniformly circumferentially arranged in the middle of the outer ring wall of the duty head (4). Multiple premixed gas injection holes (4.5) are opened on the other side of the duty head (4). The through hole on the other side of the duty head (4) is a mounting hole (4.3). The diameter of the mounting hole (4.3) is 2 mm larger than the diameter of the igniter (1). The diameter of the premixed gas injection hole (4.5) is 3 mm.

3. The premixed low-emission combustion chamber control system for a pure hydrogen gas turbine according to claim 2, characterized in that: The igniter (1) and the outer wall of the duty officer's head (4) form a duty officer cooling airflow channel (9).

4. The premixed low-emission combustion chamber control system for a pure hydrogen gas turbine according to claim 1, characterized in that: A fuel port (6.1) is provided on the top side wall of the fuel ring cavity (6). A flange sealing gasket groove (6.2) is also provided in the fuel ring cavity (6). The flange gasket (5) is placed in the flange sealing gasket groove (6.2). An installation thread (6.3) is provided below the igniter sealing gasket groove (1.1). The connecting flange (3) is connected to the fuel ring cavity (6) through the installation thread (6.3). A fuel annular flow channel (6.4) is provided inside the fuel ring cavity (6). Multiple fuel dispersion tubes (6.5) are located at the bottom of the fuel ring cavity (6). The fuel annular flow channel (6.4) is connected to the fuel dispersion tubes (6.5). The fuel dispersion tubes (6.5) are provided with nozzles (6.6).

5. The premixed low-emission combustion chamber control system for a pure hydrogen gas turbine according to claim 2, characterized in that: The igniter (1) has an igniter sealing gasket groove (1.1), and the igniter sealing gasket (2) is placed in the igniter sealing gasket groove (1.1). An external thread (1.2) is provided below the igniter sealing gasket groove (1.1). The igniter (1) is connected to the fuel ring cavity (6) through the external thread (1.2). The igniter (1) and the fuel ring cavity (6) are coaxially arranged. The bottom end of the igniter (1) is the ignition head (1.3). The ignition head (1.3) is flush with the mounting hole (4.3). A cooling ring cavity (10) is formed between the ignition head (1.3) and the mounting hole (4.3).

6. The premixed low-emission combustion chamber control system for a pure hydrogen gas turbine according to claim 5, characterized in that: The nozzle (6.6) is a pipe wall guide angle nozzle. The premixing section (4.4) is between the nozzle (6.6) and the premixing section (4.4). The nozzle (6.6) and the premixing section (4.4) are coaxially arranged. The other side of the duty head (4) is a frustum shape. The side wall of the duty head (4) is machined with a premixing air nozzle (4.5).

7. The premixed low-emission combustion chamber control system for a pure hydrogen gas turbine according to claim 6, characterized in that: The premixing section (4.4) of the duty class adopts a micro-mixing structure, and the aperture of the premixing section is 3mm.

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