A combustion chamber and a combustion control method

Abstract

The present invention relates to the technical field of gas turbines, and particularly relates to a combustion chamber and a combustion control method. The combustion chamber includes: a detonation combustion chamber located at the central axis of the combustion chamber; a plurality of main combustion nozzles arranged around the detonation combustion chamber; the combustion control method includes: after the detonation wave exits from the outlet of the detonation combustion chamber, it gradually expands and decouples to form a leading shock wave; the leading shock wave is used to ignite the fuel ejected from the main combustion nozzles and block the flashback of the main combustion nozzles. In this application, after the detonation wave exits from the outlet of the detonation combustion chamber, it gradually expands and decouples to form a leading shock wave, which propagates rapidly downstream along the flame tube. When flashback occurs to the fuel used by the main combustion nozzles, the flame propagates reversely and contacts and collides with the leading shock wave. Under the blocking effect of the leading shock wave, the flame will stop propagating near the contact surface with the leading shock wave, preventing flashback and avoiding burning damage to the combustion chamber; it is beneficial to the safe, stable and efficient combustion of the combustion chamber.

Description

Technical Field

[0001] The present invention relates to the technical field of gas turbines, and particularly relates to a combustion chamber and a combustion control method. Background Art

[0002] With the continuous development of industrial technology, gas turbines have been widely used in various industries such as energy, power, ships, and aviation. In the aviation and ship industries, gas turbines usually use liquid fuels. Heavy gas turbines for power generation usually use gaseous fuels such as natural gas; and in order to meet emission standards, dry premixed combustion is usually adopted to control the flame surface temperature and reduce pollutant emissions; however, premixed combustion has a risk of flashback. At present, domestic gas turbines have completed the adaptation transformation of natural gas blended with hydrogen combustion, and at the same time, gas turbine suppliers at home and abroad are also focusing on the research and development of gas turbines that use hydrogen as fuel entirely. However, hydrogen premixed combustion is prone to flashback, which will seriously damage the combustion chamber and even damage the gas turbine in severe cases. Summary of the Invention

[0003] Therefore, the technical problem to be solved by the present invention is to overcome the defects that when a gas turbine adopts the natural gas blended with hydrogen premixed combustion mode, it is prone to flashback, and is liable to burn out the combustion chamber and even damage the gas turbine.

[0004] In order to achieve the above object, the present invention provides a combustion chamber, including:

[0005] An intake head, a detonation combustion chamber, and a flame tube connected in sequence; the detonation combustion chamber is located on the central axis of the combustion chamber, and pulse detonation combustion is suitable to be carried out in the detonation combustion chamber;

[0006] A plurality of main fuel nozzles, arranged around the detonation combustion chamber, and one end of each of the plurality of main fuel nozzles is connected to the intake head, and the other end of each of the plurality of main fuel nozzles is connected to the flame tube;

[0007] The intake head is suitable for providing fuel for the detonation combustion chamber and the plurality of main fuel nozzles.

[0008] Optionally, the outlets of the plurality of main fuel nozzles are arranged at an angle with the central axis of the detonation combustion chamber, the outlets of the plurality of main fuel nozzles are inclined towards the central axis of the detonation combustion chamber, and the angle range is 30 to 60 degrees; the outlets of the main fuel nozzles are arranged beyond the outlet of the detonation combustion chamber.

[0009] Optionally, the intake head includes:

[0010] A first fuel chamber, which is connected to an inlet provided at the closed end of the detonation combustion chamber through a first pipeline, and the first fuel chamber is connected to the plurality of main fuel nozzles through a plurality of third pipelines respectively;

[0011] A second fuel chamber, connected to the first fuel chamber, and the second fuel chamber is communicated with an inlet provided at the closed end of the detonation combustion chamber through a second pipeline. The second fuel chamber is communicated with a plurality of main combustion nozzles through a plurality of fourth pipelines respectively.

[0012] Optionally, the first fuel chamber is a cylindrical hollow structure; the second fuel chamber is a hollow ring structure.

[0013] Optionally, the fuel in the first fuel chamber is natural gas; the fuel in the second fuel chamber is hydrogen.

[0014] Optionally, flow valves are respectively provided in the first pipeline, the second pipeline, the third pipeline and the fourth pipeline.

[0015] Optionally, a plurality of first air inlets are circumferentially provided at a position close to the closed end of the detonation combustion chamber; the first air inlets are adapted to supply air into the detonation combustion chamber.

[0016] An explosion-enhancing obstacle is provided in the detonation combustion chamber.

[0017] A flow stabilizing plate is provided at the outlet of the detonation combustion chamber close to the open end; the flow stabilizing plate is adapted to block the expansion wave diffused from the detonation combustion chamber and the gas from propagating in the reverse direction, and limit the diffused expansion wave and gas from propagating downstream of the flame tube.

[0018] Optionally, the main combustion nozzle includes:

[0019] A fuel section, composed of a connected cylindrical cavity and a conical cavity, and the fuel section is adapted to introduce fuel; a plurality of swirlers are provided on the outer periphery of the fuel section, the blades of the swirlers are hollow, and the blades are communicated with the fuel section through a conveying hole.

[0020] An air section, sleeved on the outer periphery of the fuel section and the swirler; air is accommodated in the air section; the blades are communicated with the air section through a fuel hole; the air section is communicated with the flame tube; the inlet of the air section is circular and the outlet is fan-shaped.

[0021] Optionally, it further includes:

[0022] A casing, spacedly sleeved on the outer periphery of the flame tube, and the casing is connected to the intake head, and the casing is connected to the flame tube through an intake plate; the intake plate is arranged close to the intake head; a plurality of second air inlets are provided on the intake plate; the second air inlets are adapted to introduce the air between the casing and the flame tube into the intermediate cavity formed between the intake head and the flame tube.

[0023] The flame tube is spacedly sleeved on the outer periphery of the plurality of main combustion nozzles, and the flame tube is connected to the plurality of main combustion nozzles through a support plate.

[0024] An air supply chamber is sleeved on the outer periphery of the detonation combustion chamber. One side of the air supply chamber close to the closed end of the detonation combustion chamber is connected to an air supply pipeline, and a third air inlet hole is provided on one side of the air supply chamber close to the open end of the detonation combustion chamber; the third air inlet hole is adapted to introduce the air in the air supply chamber into the flame tube.

[0025] The air supply chamber is connected to a plurality of main combustion nozzles through a support plate.

[0026] A plurality of fourth air inlet holes are provided on the support plate; the fourth air inlet holes are adapted to introduce a part of the air in the intermediate cavity into the flame tube.

[0027] The present invention also provides a combustion control method, which uses the combustion chamber described above for combustion, including:

[0028] After the detonation wave exits from the outlet of the detonation combustion chamber, it gradually expands and decouples to form a leading shock wave; the leading shock wave is used to ignite the fuel ejected by the main combustion nozzle and prevent flashback of the main combustion nozzle.

[0029] The above technical solution of the present invention has the following advantages compared with the prior art:

[0030] 1. The combustion chamber provided by the present invention includes: an intake head, a detonation combustion chamber, and a flame tube that are connected in sequence; the detonation combustion chamber is located at the central axis of the combustion chamber, and pulse detonation combustion is suitable to occur in the detonation combustion chamber; a plurality of main combustion nozzles are arranged around the detonation combustion chamber, and one end of each of the plurality of main combustion nozzles is connected to the intake head, and the other end of each of the plurality of main combustion nozzles is connected to the flame tube; the intake head is suitable for providing fuel for the detonation combustion chamber and the plurality of main combustion nozzles. With the above technical solution of the present application, after the detonation wave exits from the outlet of the detonation combustion chamber, it rapidly expands in the flame tube, causing the surrounding fresh mixture to be strongly compressed and burned, eliminating devices such as swirlers and Venturis in traditional pilot nozzles, reducing the complexity of the combustion chamber and the cost. At the same time, the fresh premixed gas of the main combustion nozzle is strongly compressed by the leading shock wave, increasing in temperature and pressure, and is ignited by the high-temperature gas behind the leading shock wave, and can continuously ignite the fresh mixture exiting from the main combustion nozzle; due to the characteristics of detonation combustion, the parameters of the detonation wave are stable, and under the same gas supply and ignition conditions, the parameters such as the pressure and speed of the detonation wave vary little. Therefore, using the detonation combustion chamber as a pilot nozzle can, like traditional continuous-burning pilot nozzles, stably ignite the fresh mixture in the flame tube and stabilize the ignition source. After the detonation wave exits from the outlet of the detonation combustion chamber, it gradually expands and decouples to form a leading shock wave, which rapidly propagates downstream along the flame tube. When flashback occurs to the fuel used by the main combustion nozzle, the flame propagates reversely and comes into contact and collision with the leading shock wave. Since the pressure of the leading shock wave is high, its speed is fast, and it has high energy, and the propagation directions of the two are opposite, the flame will stop propagating near the contact surface with the leading shock wave under the blocking effect of the leading shock wave, preventing flashback and avoiding damage to the combustion chamber, which is beneficial to the safe, stable, and efficient combustion of the combustion chamber. In addition, since detonation combustion occurs in a semi-closed narrow space, only a relatively low ignition energy is required to ignite it. Compared with the combustion chamber of a traditional gas turbine, it has lower requirements for the ignition electrode.

[0031] 2. The outlets of the multiple main combustion nozzles of the present invention are arranged at an angle with respect to the central axis of the detonation combustion chamber. The outlets of the multiple main combustion nozzles are inclined towards the central axis of the detonation combustion chamber, and the angle range is 30 to 60 degrees; the outlets of the main combustion nozzles are arranged beyond the outlet of the detonation combustion chamber. With the above technical solution of the present application, when the gas downstream of the main combustion nozzle is ejected from the main combustion nozzle, it moves along the direction close to the central axis of the flame tube. The velocity direction can be decomposed into a component moving downstream along the central axis of the flame tube and a first component moving radially inwards perpendicular to the central axis of the flame tube in a two-dimensional space. The detonation wave generated by the detonation combustion chamber and the velocity direction of the gas behind the wave can be decomposed into a component moving downstream along the central axis of the flame tube and a second component moving radially outwards perpendicular to the central axis of the flame tube. Therefore, the two perpendicular first and second components can cancel each other out, enabling the gas behind the main combustion nozzle to propagate downstream along the central axis of the flame tube, and the gas is evenly distributed in the flame tube, ensuring the uniformity of the temperature distribution at the outlet of the combustion chamber.

[0032] 3. The intake head of the present invention includes: a first fuel chamber, which is connected to the inlet provided at the closed end of the detonation combustion chamber through a first pipeline, and the first fuel chamber is respectively connected to multiple main combustion nozzles through multiple third pipelines; a second fuel chamber, which is connected to the first fuel chamber, and the second fuel chamber is connected to the inlet provided at the closed end of the detonation combustion chamber through a second pipeline, and the second fuel chamber is respectively connected to multiple main combustion nozzles through multiple fourth pipelines. With the above technical solution of the present application, since the detonation combustion characteristics are greatly related to the type of fuel, by setting the first fuel chamber and the second fuel chamber, different types of fuel can be supplied to the main combustion nozzles and the detonation combustion chamber; within the allowable range of the change in the Wobbe index of the fuel, the gas turbine can automatically switch and select the fuel supply at different working stages, improving the safety, stability and economy during the operation of the gas turbine, thereby optimizing the performance of the gas turbine.

[0033] 4. The first fuel chamber of the present invention is a cylindrical hollow structure; the second fuel chamber is a hollow ring structure. With the above technical solution of the present application, enough installation space is reserved for the first pipeline, the second pipeline, the third pipeline and the fourth pipeline through the middle gap of the hollow ring structure.

[0034] 5. The fuel in the first fuel chamber of the present invention is natural gas; the fuel in the second fuel chamber is hydrogen. With the above technical solution of the present application, within the allowable range of the change in the Wobbe index of the fuel, the combustion chamber can support the main combustion nozzle to burn with all natural gas or natural gas blended with hydrogen; it can also support the detonation combustion chamber to burn with all hydrogen, all natural gas or natural gas blended with hydrogen.

[0035] 6. The present invention is provided with flow valves in the first pipeline, the second pipeline, the third pipeline and the fourth pipeline respectively; by adopting the above technical solution, the present application controls the on-off of the pipeline and the magnitude of the fuel flow through the flow valves, and within the range allowed by the change of the Wobbe index of the fuel, the gas turbine can automatically switch the fuel supply in different working stages, and adjust the fuel flow and ratio, so as to optimize the performance of the gas turbine, and improve the safety, stability and economy of the gas turbine combustion.

[0036] 7. The present invention is circumferentially provided with a plurality of first air inlet holes at a position close to the closed end on the detonation combustion chamber; the first air inlet holes are adapted to supply air into the detonation combustion chamber; an explosion enhancement obstacle is arranged in the detonation combustion chamber; a flow stabilizing plate is arranged at the outlet close to the open end on the detonation combustion chamber; the flow stabilizing plate is adapted to block the expansion wave and the gas diffused from the detonation combustion chamber from propagating reversely, and limit the propagation of the diffused expansion wave and the gas to the downstream of the flame tube; by adopting the above technical solution, the present application accelerates the transition from deflagration to detonation through the explosion enhancement obstacle, forms a self-sustaining detonation wave propagating downstream; supplies air into the detonation combustion chamber through the first air inlet holes; when the detonation wave carries the gas and exits from the outlet, it immediately expands and diffuses around, and the flow stabilizing plate can play a physical blocking role, avoiding the reverse propagation of the diffused expansion wave and the gas, and limiting its propagation to the downstream of the combustion chamber.

[0037] 8. The main fuel nozzle of the present invention includes: a fuel section, which is composed of a connected cylindrical cavity and a conical cavity, and the fuel section is adapted to introduce fuel; a plurality of swirlers are arranged on the outer periphery of the fuel section, the blades of the swirler are hollow, and the blades are communicated with the fuel section through a conveying hole; an air section, which is sleeved on the outer periphery of the fuel section and the swirler; air is accommodated in the air section; the blades are communicated with the air section through a fuel hole; the air section is communicated with the flame tube; the inlet of the air section is circular and the outlet is fan-shaped; by adopting the above technical solution, through the setting of the shape of the fuel section, the air flow is made smooth; through the swirler, the mixing of fuel and air is more uniform, and a stable recirculation zone is formed.

[0038] 9. The combustion chamber provided by the present invention further includes: a casing, which is sleeved outside the periphery of the flame tube at intervals, and the casing is connected to the intake head, and the casing is connected to the flame tube through an intake plate; the intake plate is arranged close to the intake head; a plurality of second intake holes are provided on the intake plate; the second intake holes are adapted to introduce the air between the casing and the flame tube into the intermediate cavity formed between the intake head and the flame tube; the flame tube is sleeved outside the periphery of the plurality of main combustion nozzles at intervals, and the flame tube is connected to the plurality of main combustion nozzles through a support plate; an air supply cavity is sleeved outside the periphery of the detonation combustion chamber, one side of the air supply cavity close to the closed end of the detonation combustion chamber is connected to an air supply pipeline, and a third intake hole is provided on one side of the air supply cavity close to the open end of the detonation combustion chamber; the third intake hole is adapted to introduce the air in the air supply cavity into the flame tube; the air supply cavity is connected to the plurality of main combustion nozzles through a support plate; a plurality of fourth intake holes are provided on the support plate; the fourth intake holes are adapted to introduce a part of the air in the intermediate cavity into the flame tube; by adopting the above technical solution of the present application, part of the air required for combustion is provided through the second intake holes, the third intake holes and the fourth intake holes; and by the air flowing in the air supply cavity, the wall surface of the detonation combustion chamber is cooled; by the air flowing outside the flame tube, the wall surface of the flame tube is cooled.

[0039] 10. The combustion control method provided by the present invention uses the combustion chamber for combustion, and includes: after the detonation wave exits from the outlet of the detonation combustion chamber, it gradually expands and decouples to form a leading shock wave; using the leading shock wave to ignite the fuel ejected by the main combustion nozzle and blocking the flashback of the main combustion nozzle; by adopting the above technical solution of the present application, after the detonation wave exits from the outlet of the detonation combustion chamber, it gradually expands and decouples to form a leading shock wave, which rapidly propagates along the downstream of the flame tube. When the fuel used by the main combustion nozzle undergoes flashback, the flame propagates reversely and contacts and collides with the leading shock wave. Due to the high pressure and fast speed of the leading shock wave, it has relatively high energy, and the propagation directions of the two are opposite. Under the blocking effect of the leading shock wave, the flame will stop propagating near the contact surface with the leading shock wave, preventing flashback and avoiding burning damage to the combustion chamber, which is beneficial to the safe, stable and efficient combustion of the combustion chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0041] Figure 1 It is a schematic three-dimensional structure diagram of the combustion chamber provided in the embodiment of the present invention;

[0042] Figure 2 It is a schematic cross-sectional structure diagram of the combustion chamber provided in the embodiment of the present invention;

[0043] Figure 3 It is a schematic right-view structure diagram of the combustion chamber provided in the embodiment of the present invention.

[0044] Description of the reference numerals:

[0045] 1. First inlet; 2. First fuel chamber; 3. Second inlet; 4. Second fuel chamber; 5. First pipeline; 6. Second pipeline; 7. Inlet; 8. Third pipeline; 9. Fourth pipeline; 10. Fuel section; 11. Detonation combustion chamber; 12. Air intake hole; 13. Detonation enhancement obstacle; 14. Air supply chamber; 15. Air intake plate; 16. Support plate; 17. Air section; 18. Flow stabilizer plate; 19. Gas film hole; 20. Mixing hole; 21. Flame tube; 22. Casing; 23. Swirler; 24. Flange; 25. Second air intake hole; 26. Intermediate cavity; 27. Third air intake hole; 28. Fourth air intake hole. Detailed implementation manners

[0046] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0047] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is 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 construed as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0048] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0049] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0050] As Figures 1 to 3 shown, a specific embodiment of the combustion chamber includes an intake head, a detonation combustion chamber 11, and a flame tube 21 connected in sequence, six main combustion nozzles uniformly arranged around the detonation combustion chamber 11, and a casing 22 sleeved around the outer periphery of the flame tube 21 at intervals.

[0051] As Figure 1 shown, the casing 22 is connected to the intake head through a flange 24.

[0052] As Figure 1 and Figure 2 shown, the detonation combustion chamber 11 is located on the central axis of the combustion chamber, and pulse detonation combustion is suitable to be carried out in the detonation combustion chamber 11. Pulse detonation combustion is an unsteady combustion mode that uses intermittent detonation waves to generate thrust. Compared with ordinary slow combustion, pulse detonation combustion has advantages such as strong chemical reactions and high thermal cycle efficiency. Usually, the structure of a pulse detonation combustion chamber is simple, similar to a long straight cylinder, with one end being a closed end and the other end being an open end; fuel and oxidant enter from the closed end of the long straight cylinder and are ignited by an igniter to generate a detonation wave, and the detonation wave propagates downstream self-sustainably for unsteady self-pressurizing combustion; when it exits from the outlet of the detonation tube (i.e., the open end), it expands and decouples to carry out the exhaust process to prepare for the next detonation combustion. The front ends of the six main combustion nozzles are connected to the intake head, and the rear ends of the six main combustion nozzles are connected to the flame tube 21; the intake head is suitable for providing fuel for the detonation combustion chamber 11 and the six main combustion nozzles. The outlets of the six main combustion nozzles are arranged at an angle with the central axis of the detonation combustion chamber 11, and the outlets of the six main combustion nozzles are inclined towards the central axis of the detonation combustion chamber 11, and the angle range is 30 to 60 degrees; the outlets of the main combustion nozzles extend beyond the outlet of the detonation combustion chamber 11.

[0053] The intake head includes: a first fuel chamber 2 and a second fuel chamber 4 which are connected and arranged; specifically, the first fuel chamber 2 is a cylindrical hollow structure; the second fuel chamber 4 is a hollow ring structure; the fuel in the first fuel chamber 2 is natural gas; the fuel in the second fuel chamber 4 is hydrogen; a first inlet 1 is provided on the first fuel chamber 2 to introduce natural gas; two opposite second inlets 3 are provided on the second fuel chamber 4 to introduce hydrogen; natural gas is used as the main fuel and hydrogen is used as the auxiliary fuel. The first fuel chamber 2 is communicated with an inlet 7 provided at the closed end of the detonation combustion chamber 11 through a first pipeline 5, and the first fuel chamber 2 is communicated with six main combustion nozzles through six third pipelines 8 respectively; the second fuel chamber 4 is communicated with the inlet 7 provided at the closed end of the detonation combustion chamber 11 through a second pipeline 6, and the second fuel chamber 4 is communicated with six main combustion nozzles through six fourth pipelines 9 respectively. Further, flow valves are respectively provided on the first pipeline 5, the second pipeline 6, the third pipeline 8 and the fourth pipeline 9. Specifically, the flow valve is a servo flow valve.

[0054] A plurality of first air intake holes 12 are circumferentially provided at a position near the closed end of the detonation combustion chamber 11; the first air intake holes 12 are adapted to supply air into the detonation combustion chamber 11; an explosion enhancement obstacle 13 is provided in the detonation combustion chamber 11; a flow stabilizing plate 18 is provided at the outlet near the open end of the detonation combustion chamber 11; the flow stabilizing plate 18 is adapted to block the expansion wave diffused from the detonation combustion chamber 11 and the combustion gas from propagating in the reverse direction, and limit the diffused expansion wave and the combustion gas from propagating downstream of the flame tube 21. Specifically, the shape of the flow stabilizing plate 18 is a thin circular ring.

[0055] The main combustion nozzle includes: a fuel section 10 and an air section 17. The fuel section 10 is composed of a cylindrical cavity at the front end and a conical cavity at the rear end which are communicated, and the fuel section 10 is adapted to introduce fuel; a plurality of swirlers 23 are provided on the outer periphery of the fuel section 10, the blades of the swirlers 23 are hollow, and the blades are communicated with the fuel section 10 through a delivery hole; the air section 17 is sleeved on the outer periphery of the fuel section 10 and the swirlers 23; air is accommodated in the air section 17; the blades are communicated with the air section 17 through two fuel holes; the air section 17 is communicated with the flame tube 21. Specifically, the cross section of the front part of the air section 17 is circular, and the cross section of the rear part is a transition section from a circular cross section to a fan-shaped cross section; six transition sections are uniformly distributed along the circumference; the outlets of the six transition sections form an angle of 30 - 60 degrees with the central axis of the detonation combustion chamber 11.

[0056] As Figure 2 and Figure 3As shown, the casing 22 is connected to the combustion chamber liner 21 through the air inlet plate 15. Specifically, the air inlet plate 15 is welded to the combustion chamber liner 21. The air inlet plate 15 is disposed near the air inlet head. A plurality of second air inlet holes 25 are provided on the air inlet plate 15. The second air inlet holes 25 are adapted to introduce the air between the casing 22 and the combustion chamber liner 21 into the intermediate cavity 26 formed between the air inlet head and the combustion chamber liner 21. Specifically, the air inlet plate 15 is annular, and the second air inlet holes 25 are strip-shaped air holes. Further, a plurality of film holes 19 are provided on the outer periphery of the combustion chamber liner 21 to cool the wall surface of the combustion chamber liner 21. A plurality of mixing holes 20 are provided on the outer periphery of the combustion chamber liner 21 near the outlet position to adjust the temperature distribution at the outlet of the combustion chamber. The combustion chamber liner 21 is sleeved around the outer periphery of the six main combustion nozzles at intervals, and the combustion chamber liner 21 is connected to the six main combustion nozzles through the support plates 16. An air supply chamber 14 is sleeved around the outer periphery of the detonation combustion chamber 11. One side of the air supply chamber 14 near the closed end of the detonation combustion chamber 11 is connected to an air supply pipeline, and the air from the compressor enters the air supply pipeline. A third air inlet hole 27 is provided on one side of the air supply chamber 14 near the open end of the detonation combustion chamber 11. The third air inlet hole 27 is adapted to introduce the air in the air supply chamber 14 into the combustion chamber liner 21. That is, part of the air in the air supply chamber 14 provides air into the detonation combustion chamber 11 through the first air inlet hole 12, and the other part of the air provides air into the combustion chamber liner 21 through the third air inlet hole 27. The air supply chamber 14 is connected to the six main combustion nozzles through the support plates 16. A plurality of fourth air inlet holes 28 are provided on the support plates 16. The fourth air inlet holes 28 are adapted to introduce part of the air in the intermediate cavity 26 into the combustion chamber liner 21. The air between the casing 22 and the combustion chamber liner 21 comes from the air transmitted by the compressor to the tail of the casing 22. The air discharged from the outlet of the compressor reaches the tail of the casing 22 and successively enters the mixing holes 20 and the film holes 19. The remaining air enters the intermediate cavity 26 through the strip-shaped air holes on the air inlet plate 15, and then enters the combustion chamber liner 21 through the fourth air inlet holes 28 on the support plates 16 and the air section 17 to participate in combustion. Moreover, most of the air enters the combustion chamber liner 21 through the air section 17 to participate in combustion.

[0057] The fuel enters the detonation combustion chamber 11 through the first pipeline 5 and the second pipeline 6, and the air from the compressor enters the detonation combustion chamber 11 through the first air inlet 12. After the fuel and air are evenly mixed, they are ignited by the igniter. In the narrow combustion space, ordinary slow combustion quickly develops into deflagration combustion, and then quickly evolves into detonation combustion through the explosion-increasing obstacle 13, forming a detonation wave that self-sustains and propagates along the downstream of the detonation combustion chamber 11, and finally propagates from the outlet of the detonation combustion chamber 11, and expands and decouples to form a leading shock wave, which propagates around in the flame tube 21. The leading shock wave is followed by high-temperature combustion gas and propagates with the leading shock wave. The detonation combustion chamber 11 acts as a duty nozzle. When it is within a reasonable fuel ratio range and can excite a stable detonation wave within the ignition frequency range of the igniter, that is, when a stable ignition source is formed, the air supply process of the main combustion nozzle begins. The fuel enters the fuel section 10 of the main burner through the third pipeline 8 and the fourth pipeline 9, and then enters the blades of the swirler 23 through the delivery hole, and finally enters the air section 17 of the main burner through the two fuel holes at the blades of the swirler 23. At the same time, the air enters the air section 17 of the main burner through the intermediate cavity 26. The two begin to mix at the swirler 23. After the action of the swirler 23, the two are mixed more evenly and a stable reflux zone is formed. The fresh premixed gas propagates toward the central axis of the flame tube 21 at an angle of 30-60 degrees through the outlet of the air section 17 of the main burner. During the propagation process, the fresh premixed gas is strongly compressed by the leading shock wave and its temperature and pressure are increased, and it is ignited by the high-temperature combustion gas behind the leading shock wave, so that the main burner burns stably. Fresh premixed gas continuously flows out from the outlet of the main combustion nozzle air section 17, and detonation waves continuously flow out from the outlet of the detonation combustion chamber 11, and are decoupled to form a leading shock wave. The leading shock wave carries high-temperature combustion gas and can promptly ignite the fresh premixed gas, allowing the combustion chamber to work continuously and stably.

[0058] The present invention also provides a combustion control method, which uses the combustion chamber described above for combustion, and includes: after the detonation wave exits from the outlet of the detonation combustion chamber 11, it gradually expands and decouples to form a leading shock wave; the leading shock wave is used to ignite the fuel ejected from the main combustion nozzle and prevent flashback of the main combustion nozzle. Further, by changing the ignition frequency of the detonation combustion chamber 11, a specific number of detonation waves and leading shock waves can be excited within a specific time period. When the number is sufficient, the continuously propagating leading shock waves constantly collide with the flashback flame, which can effectively prevent flashback and is beneficial to the safe, stable and efficient combustion of the combustion chamber. When flashback occurs and the ignition frequency reaches the limit value and more detonation waves cannot be excited, the proportion of hydrogen in the main combustion nozzle can be reduced, the proportion of natural gas can be increased, and the probability of flashback can be reduced; at the same time, the proportion of hydrogen in the detonation combustion chamber 11 is increased because the detonation wave generated by the detonation combustion of hydrogen has a faster speed and higher pressure, the temperature, pressure and speed of the gas after the detonation wave are higher, and the parameters of the formed leading shock wave also increase, resulting in a better blocking effect on the flashback flame. By adjusting the servo flow valve, the type, flow rate and ratio of the fuel are changed, so that the combustion organization process of the combustion chamber is optimized in different working stages, and the safety, stability and economy of the combustion of the gas turbine are improved.

[0059] The combustion control process of the combustion chamber described in this application is briefly described as follows:

[0060] In the initial stage of combustion, to ensure the safe and stable excitation of detonation combustion, only natural gas is supplied to the detonation combustion chamber 11. When the combustion of natural gas can stably excite detonation waves, the servo flow valve on the second pipeline 6 is opened, and hydrogen is gradually supplied to the detonation combustion chamber 11 while reducing the natural gas flow rate until the detonation combustion chamber 11 can completely burn hydrogen and generate detonation waves.

[0061] After the detonation combustion chamber 11 stably burns hydrogen, natural gas is supplied to the main combustion nozzle, and the fresh premixed gas ejected from the main combustion nozzle is ignited by means of the detonation combustion chamber 11. When the main combustion nozzle continuously and stably burns, the gas turbine can increase its output. At this time, the hydrogen flow rate in the detonation combustion chamber 11 is kept unchanged, and the natural gas intake of the main combustion nozzle is increased, and more fuel is burned by the main combustion nozzle to increase the output. When the gas turbine reaches the set hydrogen-doped speed or the set combustion chamber outlet temperature and can stably burn, the servo flow valve on the fourth pipeline 9 is opened, and the hydrogen flow rate is automatically adjusted. At the same time, the servo flow valve on the third pipeline 8 automatically adjusts the natural gas flow rate, and hydrogen is doped into the natural gas for combustion until the gas turbine reaches the rated speed. This control method can significantly reduce carbon emissions. During the process of mixing hydrogen, the Wobbe index of the mixed fuel needs to be kept within the allowable fluctuation range at all times.

[0062] In the process of hydrogen mixing in the main combustion nozzle, the servo flow valve on the second pipeline 6 is controlled to reduce the hydrogen flow entering the detonation combustion chamber 11 and increase the natural gas flow. This is because the proportion of hydrogen in the premixed gas ejected from the main combustion nozzle increases, and the chemical properties of the fresh mixed gas become more active and easier to ignite. Therefore, less hydrogen is needed to generate high-energy detonation waves. The detonation waves excited when the natural gas and hydrogen mixed fuel are burned can quickly and effectively ignite the mixed gas in the main combustion nozzle. In view of the higher price of hydrogen than natural gas, the combustion control method can optimize the flow and ratio of natural gas and hydrogen at different combustion stages, thereby improving the economy of gas turbine combustion, while optimizing pollutant emissions and protecting the environment. This is because the temperature of hydrogen detonation combustion is higher. After reducing the proportion of hydrogen in the mixed fuel, the temperature of detonation combustion can be reduced, thereby reducing the generation of thermal nitrogen oxides.

[0063] Before the main combustion nozzle supplies gas, the detonation combustion chamber 11 needs to be able to stably burn hydrogen to generate a detonation wave. This is because the detonation wave excited by hydrogen detonation combustion is faster and has a higher pressure than the detonation wave excited by natural gas detonation combustion. The temperature, pressure and speed of the post-wave gas are at a higher level, which is more conducive to igniting the premixed gas of natural gas and air transmitted from the main combustion nozzle.

[0064] When the main burner is doped with hydrogen, flashback occurs and the ignition frequency reaches the limit value, and more detonation waves cannot be stimulated, the hydrogen ratio in the detonation combustion chamber 11 needs to be increased to stimulate a more energetic leading shock wave to prevent flashback. In the process of hydrogen doping in the main burner, as the amount of hydrogen doping increases, the hydrogen in the detonation combustion chamber 11 decreases proportionally, and the combustion control methods in the two cases conflict. At this time, the hydrogen ratio in the detonation combustion chamber 11 should be increased first to prevent flashback and protect the safety of the gas turbine, rather than reducing the hydrogen ratio for reasons such as combustion economy.

[0065] Obviously, the above embodiments are merely examples for clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from them are still within the protection scope of the invention.

Claims

1. A combustion chamber, characterized in that, it includes: An intake head, a detonation combustion chamber (11), and a flame tube (21) connected in sequence; the detonation combustion chamber (11) is located on the central axis of the combustion chamber, and pulse detonation combustion is suitable to be carried out in the detonation combustion chamber (11); A plurality of main combustion nozzles, arranged around the detonation combustion chamber (11), and one end of the plurality of main combustion nozzles is connected to the intake head, and the other end of the plurality of main combustion nozzles is connected to the flame tube (21); The intake head is suitable for providing fuel for the detonation combustion chamber (11) and the plurality of main combustion nozzles; The intake head includes: A first fuel chamber (2), which is communicated with an inlet (7) provided at the closed end of the detonation combustion chamber (11) through a first pipeline (5), and the first fuel chamber (2) is respectively communicated with the plurality of main combustion nozzles through a plurality of third pipelines (8); A second fuel chamber (4), connected to the first fuel chamber (2), and the second fuel chamber (4) is communicated with an inlet (7) provided at the closed end of the detonation combustion chamber (11) through a second pipeline (6), and the second fuel chamber (4) is respectively communicated with the plurality of main combustion nozzles through a plurality of fourth pipelines (9).

2. The combustion chamber according to claim 1, characterized in that, The outlets of the plurality of main combustion nozzles are arranged at an angle with the central axis of the detonation combustion chamber (11), the outlets of the plurality of main combustion nozzles are inclined towards the central axis of the detonation combustion chamber (11), and the angle range is 30 to 60 degrees; the outlets of the main combustion nozzles are arranged beyond the outlet of the detonation combustion chamber (11).

3. The combustion chamber according to claim 1, characterized in that, The first fuel chamber (2) is a cylindrical hollow structure; the second fuel chamber (4) is a hollow ring structure.

4. The combustion chamber according to claim 1, characterized in that, The fuel in the first fuel chamber (2) is natural gas; the fuel in the second fuel chamber (4) is hydrogen.

5. The combustion chamber according to claim 1, characterized in that, Flow valves are respectively provided in the first pipeline (5), the second pipeline (6), the third pipeline (8), and the fourth pipeline (9).

6. The combustion chamber according to any one of claims 1 - 5, characterized in that, A plurality of first air intake holes (12) are circumferentially provided at a position near the closed end of the detonation combustion chamber (11); the first air intake holes (12) are suitable for providing air into the detonation combustion chamber (11); An explosion enhancement obstacle (13) is provided in the detonation combustion chamber (11); A flow stabilizing plate (18) is provided at the outlet near the open end of the detonation combustion chamber (11); the flow stabilizing plate (18) is suitable for blocking the expansion wave diffused from the detonation combustion chamber (11) and the reverse propagation of the combustion gas, and restricting the propagation of the diffused expansion wave and the combustion gas to the downstream of the flame tube (21).

7. The combustion chamber according to any one of claims 1 - 5, characterized in that, The main combustion nozzle includes: The fuel section (10) is composed of a connected cylindrical cavity and a conical cavity, and the fuel section (10) is adapted to admit fuel; a plurality of swirlers (23) are provided on the outer periphery of the fuel section (10), the blades of the swirlers (23) are hollow, and the blades are communicated with the fuel section (10) through delivery holes; The air section (17) is sleeved on the outer peripheries of the fuel section (10) and the swirler (23); air is accommodated in the air section (17); the blades are communicated with the air section (17) through fuel holes; the air section (17) is communicated with the flame tube (21); the inlet of the air section (17) is circular and the outlet is fan-shaped.

8. The combustor according to any one of claims 1 - 5, characterized in that, further comprising: A casing (22) is spaced and sleeved on the outer periphery of the flame tube (21), and the casing (22) is connected to the intake head, and the casing (22) is connected to the flame tube (21) through an intake plate (15); the intake plate (15) is arranged close to the intake head; a plurality of second intake holes (25) are provided on the intake plate (15); the second intake holes (25) are adapted to admit the air between the casing (22) and the flame tube (21) into an intermediate cavity (26) formed between the intake head and the flame tube (21); The flame tube (21) is spaced and sleeved on the outer peripheries of the plurality of main combustion nozzles, and the flame tube (21) is connected to the plurality of main combustion nozzles through support plates (16); An air supply cavity (14) is sleeved on the outer periphery of the detonation combustion chamber (11), one side of the air supply cavity (14) close to the closed end of the detonation combustion chamber (11) is connected to an air supply pipeline, and a third intake hole (27) is provided on one side of the air supply cavity (14) close to the open end of the detonation combustion chamber (11); the third intake hole (27) is adapted to admit the air in the air supply cavity (14) into the flame tube (21); The air supply cavity (14) is connected to the plurality of main combustion nozzles through support plates (16); A plurality of fourth intake holes (28) are provided on the support plate (16); the fourth intake holes (28) are adapted to admit a part of the air in the intermediate cavity (26) into the flame tube (21).

9. A combustion control method, using the combustor according to any one of claims 1 - 8 for combustion, characterized in that, comprising: After the detonation wave exits from the outlet of the detonation combustion chamber (11), it gradually expands and decouples to form a leading shock wave; Using the leading shock wave to ignite the fuel ejected from the main combustion nozzle and prevent flashback of the main combustion nozzle.

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