Gas turbine combustion chamber structure suitable for ammonia fuel flameless combustion

Abstract

The invention belongs to the technical field of gas turbines, and particularly relates to a gas turbine combustion chamber structure suitable for ammonia fuel flameless combustion, which comprises an outer casing, a rotor shaft heat shield is movably connected to the middle of the inner side wall of the outer casing, an inner casing is movably connected to the outer cambered surface of the rotor shaft heat shield, and a fire tube combustion cavity is arranged between the inner casing and the outer casing. When ammonia fuel enters the large-caliber end of the conical cover ring through the air cylinder and the conical cover ring, due to the fact that the cross sectional area is large, the flow speed of the ammonia fuel is relatively low, the ammonia fuel and surrounding air have more sufficient time to be diffused and mixed, the flow speed of the ammonia fuel is increased along with gradual narrowing of a channel, and the interaction between the ammonia fuel and the air becomes more violent; the ammonia fuel and the air can be fully mixed in different stages due to the change of the flow velocity, in the stage with the slow flow velocity, the ammonia fuel and the air are slowly blended through molecular diffusion, and after the flow velocity is increased, the ammonia gas and the air are more deeply mixed under the strong convection and shearing action, so that the uniformity of the mixed gas is further improved.

Description

Technical Field

[0001] The invention belongs to the technical field of gas turbines, in particular to a gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel. Background Art

[0002] The world is facing severe climate change issues, and achieving carbon neutrality has become an important goal for all countries. Traditional gas turbines are mainly fueled by hydrocarbons such as natural gas, and combustion will emit a large amount of greenhouse gases such as carbon dioxide. Ammonia is a zero-carbon fuel, and its combustion products are ideally only nitrogen and water. Its application in gas turbines can significantly reduce carbon emissions and help promote the transformation of the energy sector to low-carbon and zero-carbon.

[0003] Over-reliance on traditional fossil fuels will expose energy supply to risks, such as resource shortages, price fluctuations, etc. The introduction of ammonia combustion technology can enrich the energy structure, reduce dependence on traditional fossil fuels, and improve the safety and stability of the energy system.

[0004] Renewable energy such as wind and solar energy is intermittent and unstable. Ammonia can be synthesized from renewable energy through electrochemical methods and become an excellent energy storage medium for renewable energy. Using ammonia for gas turbine combustion can achieve effective storage and flexible use of renewable energy, solving the limitation of renewable energy in energy supply.

[0005] The uniformity of the mixture of ammonia fuel and air is crucial to the stability and efficiency of flameless combustion. Since the physical and chemical properties of ammonia are different from those of traditional fuels, it may be difficult to achieve a good mixture of ammonia and air in the existing combustion chamber structure, so that some ammonia is discharged from the combustion chamber without fully reacting. Uneven mixing may cause local fuel concentration to be too high or too low, which in turn causes problems such as unstable combustion and hot spot formation, affecting the normal operation of the combustion chamber and the life of components.

[0006] To this end, the present invention provides a gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel. Summary of the invention

[0007] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0008] The technical solution adopted by the present invention to solve its technical problem is: the gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel described in the present invention comprises an outer casing, the middle part of the inner side wall of the outer casing is movably connected with a rotor shaft heat shield, the outer arc surface of the rotor shaft heat shield is movably connected with an inner casing, a fire tube combustion chamber is provided between the inner casing and the outer casing, a contact ring cover is fixedly installed on the outer surface of the outer casing away from the rotor shaft heat shield, the middle part of the inner side wall of the contact ring cover is movably connected with an impeller through a rotating shaft, and the impeller is connected to one side of the outer casing The side through holes are correspondingly connected, a Venturi effect end face is provided on one side of the inner arc surface of the contact ring cover, a retainer is fixedly installed on the top of the outer arc surface of the Venturi effect end face, a step end is provided on the outer arc surface of one side of the retainer, a thread is provided on the outer arc surface of the step end, the outer arc surface of the retainer close to the Venturi effect end face is an elastic structure, the end point of the inner arc surface of the retainer abuts on the outer arc surface of the Venturi effect end face, the top end of the inner arc surface of the retainer is fitted on one side surface of the contact ring cover, and the outer arc surface of the step end is threadedly connected with an air cylinder.

[0009] An air cylinder attachment is arranged at one edge of the outer arc surface of the air cylinder, an expansion part is arranged in the middle section of the inner arc surface of the air cylinder, and the top of one surface of the expansion part abuts against the inner wall of the retaining frame under the connection of threads.

[0010] The retaining frame is clamped and connected with the expansion part through a contact ring cover at the top. The expansion part is a conical structure, and a conical cover ring is penetrated and connected in the inner arc surface of the expansion part.

[0011] The outer arc surface of the conical cover ring is provided with a tightening ring, the outer arc surface of the conical cover ring is provided with an air inlet and an ammonia inlet, and a protrusion is provided at the front end of one side surface of the conical cover ring.

[0012] The outer arc surface of the protrusion is connected to the inside of the Venturi effect end surface, and a preheating cavity is provided on the top of the outer arc surface of the conical cover ring, and the preheating cavity is connected to the outside of the air cylinder.

[0013] An actuating end cover is provided at the bottom of the inner arc surface of the air cylinder, a containing groove is provided on one side of the inner arc surface of the actuating end cover, and a bearing end is provided on one side of the actuating end cover close to the containing groove.

[0014] An air inlet hole is arranged on one side surface of the actuating end cover, a gas bag is movably clamped on the inner arc surface of the accommodating groove, and an outer arc surface of the gas bag is connected to the air inlet hole correspondingly.

[0015] The surface of the bearing end is movably overlapped with an air push cover plate, the lower surface of the air push cover plate is movably clamped with a temperature control device, and the lower surface of the air push cover plate is fixedly installed with a spring.

[0016] One end of the spring is fixedly mounted on the surface of the bearing end, the bottom end of the thermostatic device penetrates into the accommodating groove and fits on the surface of the gas bag, and the gas push cover plate is adapted to the inner arc surface of the conical cover ring.

[0017] The beneficial effects of the present invention are as follows:

[0018] 1. When the ammonia fuel enters the large-diameter end of the conical cover ring through the air cylinder and the conical cover ring, the flow rate of the ammonia fuel is relatively slow due to the large cross-sectional area, and it has more time to diffuse and mix with the surrounding air. As the channel gradually narrows, the flow rate of the ammonia fuel increases, and its interaction with the air becomes more intense. This change in flow rate enables the ammonia fuel and air to be fully mixed at different stages. In the slow flow stage, the two slowly blend through molecular diffusion. After the flow rate increases, the strong convection and shearing effect promote a deeper mixing of ammonia and air, further improving the uniformity of the mixed gas.

[0019] 2. Through the air cylinder, gas bag and air push cover, as the gas bag continues to expand, the powerful thrust it generates gradually acts on the top air push cover. When the push cover moves upward, the shearing effect on the gas causes the internal ammonia and air molecules to further undergo strong mutual friction and redistribution during the process of the mixed gas being pushed. This dynamic mixing and strengthening process further improves the uniformity of the mixed gas, ensuring that the mixing ratio of ammonia and air is always maintained at the optimal state when entering the conical cover ring. When the conical cover ring receives the rapidly influx of mixed gas, the conical structure can effectively rectify and accelerate the gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below in conjunction with the accompanying drawings.

[0021] Figure 1 It is a three-dimensional diagram of the combustion chamber and the air cylinder of the present invention;

[0022] Figure 2 It is a cross-sectional internal structure display diagram of the air cylinder of the present invention;

[0023] Figure 3 is a cross-sectional view of the retainer and the air cylinder in the present invention;

[0024] Figure 4 It is a structural schematic diagram of the conical cover ring in the present invention;

[0025] Figure 5 It is a schematic diagram of the disassembled structure of the actuating end cover in the present invention;

[0026] Figure 6 It is a schematic diagram of the structure of the gas bag in the present invention.

[0027] In the figure: 1. outer casing; 101. shaft heat shield; 102. inner casing; 103. fire tube combustion chamber; 2. contact ring cover; 201. impeller; 202. Venturi effect end face; 3. retaining frame; 301. stepped end; 4. air cylinder; 401. cylinder attachment; 402. expansion part; 5. conical cover ring; 501. tightening ring; 502. air inlet; 503. ammonia inlet; 504. protrusion; 505. preheating cavity mouth; 6. actuating end cover; 601. receiving groove; 602. load-bearing end; 603. air inlet hole; 7. gas bag; 8. air push cover plate; 9. spring; 10. temperature regulating device. DETAILED DESCRIPTION

[0028] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0029] like Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, the embodiment of the present invention comprises an outer casing 1, a rotor shaft heat shield 101 is movably connected to the middle of the inner side wall of the outer casing 1, an inner casing 102 is movably connected to the outer arc surface of the rotor shaft heat shield 101, a fire tube combustion chamber 103 is provided between the inner casing 102 and the outer casing 1, a contact ring cover 2 is fixedly installed on the outer surface of the outer casing 1 away from the rotor shaft heat shield 101, an impeller 201 is movably connected to the middle of the inner side wall of the contact ring cover 2 through a rotating shaft, and the impeller 201 is connected to the outer casing 102. The through hole on one side of the casing 1 is correspondingly penetrated, and a Venturi effect end face 202 is provided on one side of the inner arc surface of the contact ring cover 2, and a retainer 3 is fixedly installed on the top of the outer arc surface of the Venturi effect end face 202, and a step end 301 is provided on the outer arc surface of one side of the retainer 3, and a thread is provided on the outer arc surface of the step end 301, and the outer arc surface of the retainer 3 close to the Venturi effect end face 202 is an elastic structure, and the end point of the inner arc surface of the retainer 3 abuts on the outer arc surface of the Venturi effect end face 202, and the retainer The top of the inner arc surface of 3 is fitted on the surface of one side of the contact ring cover 2, the outer arc surface of the step end 301 is threadedly connected with the air cylinder 4, and the air cylinder attachment 401 is provided at the edge of one side of the outer arc surface of the air cylinder 4. The middle section of the inner arc surface of the air cylinder 4 is provided with an expansion part 402, and the top of one side surface of the expansion part 402 is connected with the inner side wall of the retainer 3 under the connection of the thread, and the retainer 3 is clamped and connected with the expansion part 402 through the contact ring cover 2 at the top, and the expansion part 402 is a conical structure. A conical cover ring 5 is connected to the inner arc surface of the part 402, a tightening ring 501 is provided on the outer arc surface of the conical cover ring 5, an air inlet 502 and an ammonia inlet 503 are provided on the outer arc surface of the conical cover ring 5, a protrusion 504 is provided at the front end of the surface of one side of the conical cover ring 5, the outer arc surface of the protrusion 504 is connected to the inside of the Venturi effect end face 202, a preheating cavity opening 505 is provided on the top of the outer arc surface of the conical cover ring 5, and the preheating cavity opening 505 extends to the outside of the air cylinder 4.

[0030] The inner casing 102 is opposite to the outer casing 1, defining the spatial range within the combustion chamber, and especially cooperating with the fire tube combustion chamber 103 to provide a relatively closed space for the combustion of ammonia fuel, which can withstand the high temperature and pressure generated during the combustion process and ensure that the combustion is carried out in a specific area. Orifices are set on the outer arc surface of the inner casing 102 to allow air to enter the fire tube combustion chamber 103 at a specific angle and speed, and achieve good mixing with the injected ammonia fuel, creating favorable conditions for flameless combustion. The fire tube combustion chamber 103 is the core area for flameless combustion of ammonia fuel. Ammonia fuel and properly mixed air undergo violent chemical reactions in this cavity, releasing a large amount of heat energy.

[0031] When the ammonia fuel is introduced into the air cylinder 4 before entering the fire tube combustion chamber 103, the ammonia fuel will float on the top of the air cylinder 4 after entering because of its lower density than air. The air and ammonia will mix autonomously without contacting the conical cover ring 5. The interior of the air cylinder 4 will be filled with the continuous mixing of air and ammonia. During the autonomous mixing, the ammonia nozzle tube is corresponded to the ammonia inlet 503 due to the correspondence of the outer arc surface air inlet of the conical cover ring 5. At the same time, an electric heating conductor is installed on the preheating cavity mouth 505 on the top. Under the preheating of the temperature, the activity of the ammonia is improved. Since the ignition temperature of ammonia is relatively high, the preheating can effectively reduce the energy threshold required for its ignition, laying the foundation for the subsequent efficient and stable combustion in the fire tube combustion chamber 103.

[0032] As the mixed gas accumulates in the air cylinder 4, the pressure gradually rises, prompting the mixed gas to flow to one side in an orderly manner through the air inlet of the conical cover ring 5. The structure of the conical cover ring 5, which is large in front and small in the back, guides the mixed gas to enter the subsequent channel at a specific flow rate and direction. In this process, the rotation of the impeller 201 will guide the mixed gas, and the flow state of the mixed gas will be further optimized. The contact between ammonia and air will be closer, and the uniformity of mixing will continue to improve. In order to further enhance the mixing effect, an expansion part 402 is set inside the air cylinder 4. The expansion part 402 is a tapered structure. When the ammonia fuel flows through, it will The contact surface of the large diameter gradually changes into the contact surface of the small diameter. When the ammonia fuel enters the large diameter end of the expansion part 402, due to the large cross-sectional area, the flow rate of the ammonia fuel is relatively slow, and it has more sufficient time to diffuse and mix with the surrounding air. As the channel gradually narrows, the flow rate of the ammonia fuel increases, and its interaction with the air becomes more intense. This change in flow rate enables the ammonia fuel and air to be fully mixed at different stages. In the slow flow stage, the two slowly blend through molecular diffusion. After the flow rate increases, the strong convection and shearing effect promote a deeper mixing of ammonia and air, further improving the uniformity of the mixed gas.

[0033] Moreover, the inner wall of the expansion part 402 is not a smooth surface, but is sleeved with a conical cover ring 5. Since the structure of the conical cover ring 5 is the same as that of the expansion part 402, the ammonia fuel and the air will interact again, disrupting the flow of the mixed gas of the ammonia fuel and the air, aggravating the degree of turbulence, and increasing the collision probability of the ammonia gas and the air molecules exponentially, thus promoting the mixing process. Moreover, the expansion part 402 can also compress the mixed gas to a certain extent. As the mixed gas flows out from the small-caliber end, the pressure increases slightly, which not only helps the subsequent stable delivery of the gas in the pipeline, but also makes the molecular distance inside the mixed gas closer before entering the fire tube combustion chamber 103, further enhancing the mixing effect, and providing a better quality mixed gas condition for the ammonia fuel to achieve efficient, stable and low-pollution flameless combustion in the fire tube combustion chamber 103.

[0034] like Figure 2 , Figure 3 , Figure 5 and Figure 6 As shown, an actuating end cover 6 is provided at the bottom of the inner arc surface of the air cylinder 4, a receiving groove 601 is provided on one side of the inner arc surface of the actuating end cover 6, a bearing end 602 is provided on the side of the actuating end cover 6 close to the receiving groove 601, an air inlet hole 603 is provided on one side surface of the actuating end cover 6, a gas bag 7 is movably connected to the inner arc surface of the receiving groove 601, an outer arc surface of the gas bag 7 is correspondingly connected to the air inlet hole 603, an air push cover plate 8 is movably overlapped on the surface of the bearing end 602, a thermostat 10 is movably connected to the lower surface of the air push cover plate 8, a spring 9 is fixedly installed on the lower surface of the air push cover plate 8, one end of the spring 9 is fixedly installed on the surface of the bearing end 602, the bottom end of the thermostat 10 passes through the receiving groove 601 and fits on the surface of the gas bag 7, and the air push cover plate 8 is adapted to the inner arc surface of the conical cover ring 5.

[0035] When the gas inside the air cylinder 4 is compressed, it will enter the air inlet 603 of the actuator end cover 6 at high speed. As the gas is continuously injected, the gas bag 7 closely corresponding to the air inlet 603 begins to be gradually filled. Under the continuous inflow of gas, the gas bag 7 continues to expand like a balloon. As the gas bag 7 expands, its volume continues to increase, and it begins to gradually occupy the space inside the air cylinder 4. Since the gas bag 7 occupies the space where the air and ammonia mixed gas originally existed, the internal mixed gas is squeezed, and the originally relatively loose molecular spacing of the mixed gas is further compressed and reduced.

[0036] During this process, the expansion of the gas bag 7 is not irregular. Its material has certain elasticity and adaptability, and can expand evenly according to the change of internal gas pressure. At the same time, the expansion of the gas bag 7 will be squeezed out from the receiving groove 601 in the actuating end cover 6, and continue to approach the conical cover ring 5. When it expands and squeezes the mixed gas in the air cylinder 4, it will speed up the flow of the mixed gas from the small-diameter end, and further promote the redistribution and mixing of ammonia and air molecules in the mixed gas. Even in the compression process, it can ensure that the uniformity of the mixture will not be destroyed. Moreover, as the gas bag 7 continues to expand, its compression effect on the mixed gas inside the air cylinder 4 gradually increases, so that the pressure of the mixed gas is further increased, and the temperature also rises slightly. This change in pressure and temperature is not only beneficial for the mixed gas to maintain good fluidity when it subsequently enters the fire tube combustion chamber 103.

[0037] As the gas bag 7 continues to expand, the powerful thrust it generates gradually acts on the top air push cover plate 8. Under the action of this thrust, the air push cover plate 8 begins to move upward smoothly and powerfully. During the upward movement of the air push cover plate 8, the spring 9 connected to it is also gradually pulled up. The deformation degree of the spring 9 continues to increase, storing a large amount of elastic potential energy. At this time, the air cylinder 4 is like the mixed gas inside the air cylinder, driven by the pressure brought by the expansion of the gas bag 7 and the auxiliary thrust generated by the upward movement of the air push cover plate 8, and is pushed to the inside of the conical cover ring 5 at a high speed.

[0038] During this pushing process, the mixed gas does not simply translate as a whole. There are slight differences in the pressure exerted on the mixed gas at different positions when the gas bag 7 expands, and the shearing effect on the gas when the gas push cover plate 8 moves upward causes the ammonia and air molecules inside the mixed gas to further undergo intense mutual friction and redistribution during the pushing process. This dynamic mixing and intensification process further improves the uniformity of the mixed gas, ensuring that the mixing ratio of ammonia and air is always maintained at an optimal state when entering the conical cover ring 5. When the conical cover ring 5 receives the rapidly influx of mixed gas, the conical structure can effectively rectify and accelerate the gas.

[0039] The above-mentioned front, back, left, right, top and bottom are all based on the figures in the specification. Figure 1 As a benchmark, according to the person's observation perspective, 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.

[0040] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present invention.

[0041] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel, characterized in that: The invention comprises an outer casing (1), wherein a rotor shaft heat shield (101) is movably connected to the middle of the inner side wall of the outer casing (1), an inner casing (102) is movably connected to the outer arc surface of the rotor shaft heat shield (101), a fire tube combustion chamber (103) is provided between the inner casing (102) and the outer casing (1), a contact ring cover (2) is fixedly installed on the outer surface of the side of the outer casing (1) away from the rotor shaft heat shield (101), an impeller (201) is movably connected to the middle of the inner side wall of the contact ring cover (2) via a rotating shaft, the impeller (201) is correspondingly connected to a through hole on one side of the outer casing (1), and a side of the inner arc surface of the contact ring cover (2) is fixedly mounted on the outer surface of the outer casing (1) away from the rotor shaft heat shield (101). A Venturi effect end face (202) is provided, a retainer (3) is fixedly mounted on the top of the outer arc surface of the Venturi effect end face (202), a step end (301) is provided on the outer arc surface of one side of the retainer (3), a thread is provided on the outer arc surface of the step end (301), an outer arc surface of the retainer (3) close to the Venturi effect end face (202) is an elastic structure, an inner arc surface end point of the retainer (3) abuts against the outer arc surface of the Venturi effect end face (202), a top end of the inner arc surface of the retainer (3) fits on a side surface of a contact ring cover (2), and an air cylinder (4) is threadedly connected to the outer arc surface of the step end (301).

2. A gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel according to claim 1, characterized in that: An air cylinder attachment (401) is provided at one edge of the outer arc surface of the air cylinder (4), an expansion portion (402) is provided in the middle section of the inner arc surface of the air cylinder (4), and the top of one side surface of the expansion portion (402) abuts against the inner side wall of the retaining frame (3) through a threaded connection.

3. A gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel according to claim 2, characterized in that: The retaining frame (3) is clamped and connected to the expansion part (402) through the contact ring cover (2) at the top; the expansion part (402) is a conical structure, and a conical cover ring (5) is connected and penetrated through the inner arc surface of the expansion part (402).

4. A gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel according to claim 3, characterized in that: The outer arc surface of the conical cover ring (5) is provided with a tightening ring (501), the outer arc surface of the conical cover ring (5) is provided with an air inlet (502) and an ammonia inlet (503), and a protrusion (504) is provided at the front end of one side surface of the conical cover ring (5).

5. A gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel according to claim 4, characterized in that: The outer arc surface of the protrusion (504) is connected to the inside of the Venturi effect end surface (202), and a preheating cavity opening (505) is provided at the top of the outer arc surface of the conical cover ring (5), and the preheating cavity opening (505) is connected to the outside of the air cylinder (4).

6. A gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel according to claim 5, characterized in that: An actuating end cover (6) is provided at the bottom of the inner arc surface of the air cylinder (4), a receiving groove (601) is provided on one side of the inner arc surface of the actuating end cover (6), and a bearing end (602) is provided on a side of the actuating end cover (6) close to the receiving groove (601).

7. A gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel according to claim 6, characterized in that: An air inlet hole (603) is provided on one side surface of the actuating end cover (6), a gas bag (7) is movably engaged with the inner arc surface of the accommodating groove (601), and an outer arc surface of the gas bag (7) is connected to the air inlet hole (603) in a corresponding manner.

8. A gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel according to claim 7, characterized in that: The surface of the bearing end (602) is movably overlapped with an air push cover plate (8), the lower surface of the air push cover plate (8) is movably clamped with a temperature control device (10), and the lower surface of the air push cover plate (8) is fixedly mounted with a spring (9).

9. A gas turbine combustion chamber structure suitable for flameless combustion of ammonia fuel according to claim 8, characterized in that: One end of the spring (9) is fixedly mounted on the surface of the bearing end (602), the bottom end of the thermostatic device (10) penetrates into the accommodating groove (601) and fits on the surface of the gas bag (7), and the air push cover plate (8) is adapted to the inner arc surface of the conical cover ring (5).

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