A porous evaporating tube type fuel staging multi-nozzle combustion chamber

Abstract

The application discloses a porous evaporation pipe type fuel grading multi-nozzle combustion chamber, which comprises a head end wall, a fuel supply assembly and a flame tube, wherein the fuel supply assembly comprises a duty class nozzle structure, multiple auxiliary combustion nozzle structures and multiple main combustion nozzle structures; the duty class nozzle structure is arranged at a center position; and each auxiliary combustion nozzle structure is arranged in a dispersed manner in a circumferential direction with two main combustion nozzle structures arranged between the auxiliary combustion nozzle structures. The main combustion nozzle structure adopts a porous evaporator and is provided with a three-stage air inlet structure; the first two stages are reverse swirls, and the third stage is straight flow; and the shear of the two-stage reverse swirl air flow makes the oil-gas mixture more uniform. The duty class nozzle structure is provided with a restricted domain with a three-stage progressive eccentric air inlet hole, so that the duty class flame is isolated from the main combustion cold air, and quenching is avoided. The application has the advantages of high combustion efficiency, stable structure, small volume and low nitrogen oxide emission.

Description

Technical Field

[0001] This invention belongs to the field of gas turbine combustion chamber technology, and more specifically relates to a porous evaporator tube type fuel staged multi-nozzle combustion chamber. Background Technology

[0002] Numerous research institutions have shown that staged LDI combustion schemes can effectively reduce nitrogen oxide emissions, particularly NOx emissions. x Emissions are more than 80% lower than those specified in CAEP / 6. However, the current technology has the following problems:

[0003] (1) In existing multi-nozzle combustion chambers, the main combustion stage nozzles all operate in a non-premixed combustion mode. The fuel and air are not fully mixed, and there are areas with uneven stoichiometric ratios of reactants, which can cause the generation of local high-temperature zones and local NO. x The generation rate is too high.

[0004] (2) Both the main combustion nozzle and the standby nozzle employ swirling combustion. The swirling flow results in a larger flame expansion angle, and the standby flame and the main combustion flame have a large interaction area, generating a higher heat release rate, leading to a higher flame temperature, and also causing localized NO2. x Too high, lower NO x Their capabilities are limited.

[0005] (3) The duty nozzle adopts the same structure as the main combustion nozzle, and the outlet of the duty nozzle and the main combustion nozzle are in the same axial section. When only the central duty flame is working, the cold airflow of the outer main combustion stage will have a cooling quenching effect on the central duty flame, resulting in a deterioration of the fuel-air ratio performance of the combustion chamber.

[0006] (4) In the prior art, the main combustion nozzle adopts a vortex and a venturi tube structure of contraction and expansion section, which results in an excessively large radial dimension and a large head height of the main combustion nozzle, making it unsuitable for use in the compact casing space of the combustion chamber of the gas turbine of existing ships.

[0007] Currently, extensive research has been conducted both domestically and internationally on low-emission combustors, resulting in numerous related patent applications. For example, Chinese invention patent application number 201710343294.1 discloses a lean multi-point direct injection head for a low-emission combustor in a gas turbine. This head employs staged combustion technology, dividing combustion into a main combustion stage and a secondary combustion stage through multi-point direct injection. It utilizes multiple identical swirl nozzle molds, with the secondary combustion stage swirl nozzle mold positioned at the center. The secondary combustion stage swirl nozzles and the main combustion stage swirl nozzle molds are circumferentially spaced to ensure stable combustion and reduce pollutant emissions under various operating conditions. However, this invention still fails to address the aforementioned technical problems of uneven fuel-air mixing, susceptibility of the secondary combustion stage to cold air from the main combustion stage, leading to lean fuel quenching, deteriorated fuel-air ratio performance, and the generation of large amounts of nitrogen oxides.

[0008] Chinese invention patent application number 201810741853.9 discloses a perforated multi-point direct injection swirler and a perforated multi-point direct injection head structure. It is equipped with a seven-point air nozzle mold, divided into a duty stage and a main combustion stage. By setting air inlets with different angles and diameters in the perforated swirler, the oil and gas are mixed evenly, effectively avoiding the problems of spontaneous combustion and backfire. However, the design of the swirler results in a large volume of the entire combustion chamber head, which cannot be adapted to the compact casing space of the combustion chamber of the gas turbine of existing ships. In addition, the concave design and the angled air inlets result in a large flame expansion angle. There is a large interaction area between the duty flame and the main combustion flame, which produces a higher heat release rate. The local high temperature will produce more nitrogen oxides, resulting in higher emissions.

[0009] Therefore, there is an urgent need for a combustion chamber that can solve the above problems in the combustion chambers of diesel-fueled ships and industrial gas turbines in my country. Summary of the Invention

[0010] This invention addresses the problems of high nitrogen oxide emissions, narrow stable operating range, and limited internal space of diesel-fueled ship and industrial gas turbine combustion chambers in my country. It provides a multi-hole evaporator tube type fuel staged multi-nozzle combustion chamber with the advantages of high combustion efficiency, stable structure, small size, and low nitrogen oxide emissions.

[0011] To achieve the above objectives, the present invention adopts the following technical solution:

[0012] A multi-nozzle, multi-stage fuel combustion chamber with a porous evaporator tube includes a head end wall, a fuel supply assembly, and a flame tube. The fuel supply outlet of the fuel supply assembly is flush with one end of the head end wall. The front end of the flame tube is fixedly connected to the other end of the head end wall. The head end wall has multiple main stage mounting holes and one shifter mounting hole, each corresponding to one of the fuel supply assemblies. The shifter mounting hole is located at the center of the head end wall, and the multiple main stage mounting holes are arranged in a ring around the shifter mounting hole. The fuel supply assembly includes a shifter nozzle structure, multiple auxiliary combustion nozzle structures, and multiple main combustion nozzle structures. The shifter nozzle structure is connected to the shifter mounting hole, and the multiple auxiliary combustion nozzle structures and multiple main combustion nozzle structures are arranged in a ring corresponding to the main stage mounting holes.

[0013] Furthermore, the fuel supply assembly includes a duty nozzle structure, three auxiliary combustion nozzle structures, and six main combustion nozzle structures. The head end wall is provided with nine main stage mounting holes and one duty nozzle mounting hole corresponding to the fuel supply assembly. The duty nozzle mounting hole is located at the center of the head end wall, and the nine main stage mounting holes are arranged in a ring around the duty nozzle mounting hole. The three auxiliary combustion nozzle structures and the six main combustion nozzle structures are arranged in a ring corresponding to the main stage mounting holes, and each auxiliary combustion nozzle structure is dispersedly arranged two main combustion nozzle structures apart.

[0014] Furthermore, the oil supply outlet at one end of the duty nozzle structure is welded to the end wall of the head; the duty nozzle structure includes a second centrifugal nozzle, a first-stage cyclone, a second-stage cyclone, a cyclone cup sleeve, a duty cyclone cover plate, and a confinement area; the first-stage cyclone, the second-stage cyclone, and the cyclone cup sleeve are integrally formed; the first-stage cyclone has a through hole in the middle, which is fixed to the second centrifugal nozzle; the cyclone cup sleeve and the confinement area are fixedly connected by the duty cyclone cover plate; the outer wall of the end of the confinement area is stepped, and the side of the stepped outer wall is provided with a three-stage progressive eccentric air inlet, the opening direction of which is at a certain angle to the radial direction; a number of uniformly arranged cooling holes are provided downstream of the three-stage progressive eccentric air inlet of the confinement area.

[0015] Furthermore, one end of the cyclone cup sleeve is provided with a boss, and the front end of the limiting domain is provided with a groove. The boss is embedded in the groove, and the duty cyclone cover plate is bolted to the limiting domain to fix the cyclone cup sleeve and the limiting domain.

[0016] Furthermore, the auxiliary combustion nozzle structure and the main combustion nozzle structure have the same internal structure; the auxiliary combustion nozzle structure includes a porous evaporator tube, an oil inlet tube, and a first centrifugal nozzle; the oil inlet tube is externally threaded to the porous evaporator tube; the oil inlet tube is internally threaded to the first centrifugal nozzle; the porous evaporator tube wall is provided with three stages of air inlet holes in sequence, the first two stages of air inlet holes are reverse oblique holes, and the third stage of air inlet hole is a straight hole; the porous evaporator tube is provided with a flow guiding channel inside.

[0017] Furthermore, the oil inlet pipe is connected to the porous evaporator pipe at one end in a stepped shape, and the stepped part of the oil inlet pipe is sealed to the porous evaporator pipe by a copper gasket.

[0018] Furthermore, the auxiliary combustion nozzle structure, the main combustion nozzle structure, and the head end wall are connected by a connecting structure.

[0019] Furthermore, the connection structure includes a main stage floating ring outer pressure plate, a main stage floating ring inner pressure plate, and a main stage floating ring; the head end wall is fixedly connected to the main stage floating ring outer pressure plate and the head end wall is fixedly connected to the main stage floating ring inner pressure plate; the main stage floating ring outer pressure plate has a slot at its center that matches the main stage mounting hole, and the main stage floating ring inner pressure plate has a slot on its outer edge that matches the main stage mounting hole; the main stage floating ring is disposed in the slot after the main stage floating ring outer pressure plate and the main stage floating ring inner pressure plate are fitted together, and is fixed to the head end wall by the main stage floating ring outer pressure plate and the main stage floating ring inner pressure plate; the multi-hole evaporator tube has an annular protrusion on the tube wall away from the oil inlet; the annular protrusion and the main stage floating ring are fitted together with a clearance to fix the multi-hole evaporator tube to the head end wall.

[0020] Furthermore, the head end wall has a groove at its center that matches the outer diameter of the outer pressure plate of the main floating ring, and two cylindrical protrusions are provided between the main mounting holes; the outer pressure plate of the main floating ring has a through hole with the same diameter as the outer ring protrusion between its holes and grooves; the inner pressure plate of the main floating ring has a through hole with the same diameter as the inner ring protrusion between its holes and grooves; the outer pressure plate of the main floating ring and the inner pressure plate of the main floating ring are embedded in the head end wall, the protrusions cooperate with the through holes, and are fixed to the protrusions by bolts.

[0021] Furthermore, cooling holes are evenly provided around the main mounting hole and the duty mounting hole for cooling the side of the head end wall that contacts the flame.

[0022] The beneficial effects of this invention are as follows:

[0023] This invention provides a multi-nozzle, perforated evaporator-type fuel staged combustion chamber for use in ship gas turbine combustion chambers, offering three fuel supply modes. By controlling the fuel supply components to supply fuel to combustion in stages under different operating conditions, the temperature fluctuations in the combustion chamber are stabilized, resulting in higher combustion efficiency and lower nitrogen oxide emissions.

[0024] The main combustion stage nozzle structure of this invention employs a pre-mixed and pre-evaporated porous evaporator. A three-stage air intake mode is set on the porous evaporator tube wall, allowing the fuel mist to completely evaporate and mix with air under the combined action of the three airflows. This results in a more uniform temperature in the combustion chamber, reducing the risk of uneven equivalence ratios caused by excessively high local temperatures, which could damage the combustion chamber. Simultaneously, the two-stage counter-swirling airflow shearing reduces the tangential velocity, thereby decreasing the expansion angle of the main combustion flame and the interaction area between the main combustion flame and the standby flame, effectively reducing the formation of nitrogen oxides.

[0025] When the duty nozzle structure is in operation, the airflow enters the duty nozzle in stages. The confinement area of ​​the duty nozzle separates the duty flame from the main combustion cold airflow, avoiding the quenching effect of the main combustion cold airflow on the duty flame and improving the lean flame quenching performance of the combustion chamber. With the injection of air through the three-stage progressive eccentric air inlet, the duty flame gradually decreases in stoichiometry downstream, making combustion more stable, improving combustion efficiency, and effectively reducing the formation of nitrogen oxides.

[0026] In addition, since the diameter of the porous evaporator tube is much smaller than that of the conventional cyclone structure, the requirements for the head height are not high, and it can be applied in the compact casing space of the combustion chamber of the gas turbine in active ships. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the structure of the porous evaporator tube type fuel staged multi-nozzle combustion chamber of the present invention.

[0029] Figure 2 This is a schematic diagram of the oil supply component structure of the present invention.

[0030] Figure 3 This is a schematic diagram of the head end wall structure of the present invention.

[0031] Figure 4 This is a schematic diagram of the structure of the inner pressure plate of the main floating ring of the present invention.

[0032] Figure 5 This is a schematic diagram of the structure of the outer pressure plate of the main floating ring of the present invention.

[0033] Figure 6 This is a schematic diagram of the main floating ring structure of the present invention.

[0034] Figure 7 This is a schematic diagram of the combined connection structure of the present invention.

[0035] Figure 8 for Figure 7 BB section view.

[0036] Figure 9 for Figure 8 Enlarged view of point C.

[0037] Figure 10 for Figure 2 Sectional view of AA.

[0038] Figure 11 for Figure 10 Enlarged view of point D in the middle.

[0039] Figure 12 This is a schematic diagram of the secondary combustion nozzle structure and the main combustion nozzle structure.

[0040] Figure 13 This is a structural diagram of the nozzle structure for duty.

[0041] In the figure:

[0042] 1-Head end wall; 2-Duty nozzle structure; 3-Secondary main combustion stage nozzle structure; 3a-First secondary combustion nozzle structure; 3b-Secondary secondary combustion nozzle structure; 3c-Third secondary combustion nozzle structure; 4-Main combustion stage nozzle structure; 4a-First main combustion nozzle structure; 4b-Secondary main combustion nozzle structure; 4c-Third main combustion nozzle structure; 4d-Fourth main combustion nozzle structure; 4e-Fifth main combustion nozzle structure; 4f-Sixth main combustion nozzle structure; 5-Outer pressure plate of main stage floating ring; 6-Inner pressure plate of main stage floating ring; 7-Flame tube; 8-Main stage floating ring; 9-Inlet pipe; 10-Copper pad; 11-Porous evaporator tube; 12-First centrifugal nozzle; 13-Second centrifugal nozzle; 14-First cyclone separator; 15-Second cyclone separator; 16-Symphony cup sleeve; 17-Duty cyclone separator cover plate; 18-Restriction area; 19-Annular protrusion; 20-Protrusion. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Please see the appendix Figure 1 The present invention provides a multi-nozzle combustion chamber for fuel staged combustion, comprising: a head end wall 1, a fuel supply assembly and a flame tube 7; the fuel supply outlet of the fuel supply assembly is flush with one end of the head end wall 1; the flame tube 7 is cylindrical, and its front end is fixedly connected to the other end of the head end wall 1, with the connection sealed by a graphite gasket.

[0045] Please see the appendix Figure 2-3The head end wall 1 is provided with multiple main stage mounting holes and one duty officer mounting hole corresponding to the oil supply assembly. The duty officer mounting hole is located at the center of the head end wall 1, and the multiple main stage mounting holes are arranged in a ring around the duty officer mounting hole. In this embodiment, there are nine main stage mounting holes. Cooling holes are uniformly provided around both the main stage mounting holes and the duty officer mounting hole for cooling the side of the head end wall 1 that is in contact with the flame.

[0046] The fuel supply assembly includes a duty nozzle structure 2, multiple auxiliary combustion nozzle structures 3, and multiple main combustion nozzle structures 4. In this embodiment, the fuel supply assembly includes a duty nozzle structure 2, three auxiliary combustion nozzle structures 3, and six main combustion nozzle structures 4. The three auxiliary combustion nozzle structures 3 are respectively a first auxiliary combustion nozzle structure 3a, a second auxiliary combustion nozzle structure 3b, and a third auxiliary combustion nozzle structure 3c. The six main combustion nozzle structures are respectively a first main combustion nozzle structure 4a, a second main combustion nozzle structure 4b, a third main combustion nozzle structure 4c, a fourth main combustion nozzle structure 4d, a fifth main combustion nozzle structure 4e, and a sixth main combustion nozzle structure 4f. The duty nozzle structure 2 is connected to the duty mounting hole. The three auxiliary combustion nozzle structures 3 and the six main combustion nozzle structures 4 are arranged in a ring with the main combustion mounting hole. Each auxiliary combustion nozzle structure 3 is dispersed between two main combustion nozzle structures 4.

[0047] Please see the appendix Figure 13 The oil supply outlet at one end of the duty nozzle structure 2 is welded to the head end wall 1. The duty nozzle structure 2 includes a second centrifugal nozzle 13, a first-stage hydrocyclone 14, a second-stage hydrocyclone 15, a hydrocyclone cup sleeve 16, a duty hydrocyclone cover plate 17, and a confinement area 18. The first-stage hydrocyclone 14, the second-stage hydrocyclone 15, and the hydrocyclone cup sleeve 16 are 3D printed integral hydrocyclone cup structures. The first-stage hydrocyclone 14 has a through hole in the middle, which is fixed to the second centrifugal nozzle 13. The connecting end of the second centrifugal nozzle 13 has a stepped structure to control the axial depth of the second-stage hydrocyclone 14. Guides are provided between the first-stage hydrocyclone 14 and the second centrifugal nozzle 13, and between the second-stage hydrocyclone 15 and the hydrocyclone cup sleeve 16. The secondary cyclone separator 15 has a converging guide channel at the other end to transport the oil mist sprayed from the second centrifugal nozzle 13 into the cyclone cup sleeve 16. One end of the cyclone cup sleeve 16 has a boss, and the front end of the limiting region 18 has a groove. The boss is embedded in the groove. The duty cyclone separator cover plate 17 is bolted to the limiting region 18 to fix the cyclone cup sleeve 16 and the limiting region 18. The outer wall of the end of the limiting region 18 is stepped, and the inner diameter increases. The stepped sidewall has three progressive eccentric air inlets with the opening direction at a certain angle to the radial direction. Downstream of the eccentric air inlets of the limiting region 18, there are several uniformly arranged cooling holes. Cooling gas enters the limiting region 18 from the cooling holes to cool the inner surface of the limiting region 18.

[0048] Please see the appendix Figure 12 The auxiliary combustion nozzle structure 3 and the main combustion nozzle structure 4 have the same internal structure. Referring to the attached drawings, the auxiliary combustion nozzle structure 3 includes a porous evaporator tube 11, an oil inlet pipe 9, and a first centrifugal nozzle 12. One end of the oil inlet pipe 9 is stepped, and its sidewall has external threads. One end of the porous evaporator tube 11 has internal threads, and one end of the oil inlet pipe 9 is threadedly connected to the porous evaporator tube 11. A copper gasket 10 seals the stepped portion of the oil inlet pipe 9 with the porous evaporator tube 11. The inside of the oil inlet pipe 9 is stepped, and its inner wall has internal threads. One end of the first centrifugal nozzle 12 has external threads, and the first centrifugal nozzle 12 is located inside the porous evaporator tube and threadedly connected to the oil inlet pipe 9.

[0049] The porous evaporator tube 11 has a reduced inner diameter after the thread is completed, and a flow guide channel is provided in the center. Downstream of the flow guide channel is the oil-gas mixing area, where the inner diameter increases. The porous evaporator tube 11 has three stages of air inlets sequentially arranged on its wall. The diameter of the first stage air inlet is 3.5-4.5 mm, the diameter of the second stage air inlet is 5-6 mm, and the diameter of the third stage air inlet is 5-6 mm. The first two stages of air inlets are reverse-oriented oblique holes. The first stage air inlet is located at the front end of the centrifugal nozzle 9 outlet, and the second stage air inlet is located downstream of the first stage air inlet, within the oil-gas mixing area. The third stage air inlet is a straight hole, located downstream of the second air inlet. With the three-stage air intake of the porous evaporator tube 11, the oil mist sprayed from the first centrifugal nozzle 12 evaporates rapidly and mixes with air under the action of the two reverse-oriented oblique holes and one straight hole air inlet of the porous evaporator tube 11. It can be completely evaporated at the outlet of the porous evaporator tube 11, resulting in a uniformly mixed fuel vapor and air mixture.

[0050] Please see the appendix Figure 4-11 Taking the auxiliary combustion nozzle structure 3a as an example, the auxiliary combustion nozzle structure 3, the main combustion nozzle structure 4, and the head end wall 1 are fixed together by a connecting structure; the connecting structure includes a main stage floating ring outer pressure plate 5, a main stage floating ring inner pressure plate 6, and a main stage floating ring 8; the head end wall 1 has a groove at its center that matches the outer diameter of the main stage floating ring outer pressure plate 5, and two cylindrical protrusions 20 are provided between the main stage mounting holes, with nine outer ring protrusions and nine inner ring protrusions. The part is provided with a threaded structure; the outer pressure plate 5 of the main floating ring has a groove in the center that matches the main stage mounting hole, and a through hole with the same diameter as the outer ring protrusion is provided between each groove; the outer edge of the inner pressure plate 6 of the main floating ring has a groove that matches the main stage mounting hole, and a through hole with the same diameter as the inner ring protrusion is provided between each groove; the outer pressure plate 5 of the main floating ring and the inner pressure plate 6 of the main floating ring are embedded in the head end wall 1, the protrusion 20 cooperates with the through hole, and is fixed to the protrusion 20 by bolts.

[0051] like Figures 11-12 As shown, the porous evaporator tube 11 has an annular protrusion 19 on the tube wall away from the oil inlet end; the main stage floating ring 8 is disposed in the groove after the main stage floating ring outer pressure plate 5 and the main stage floating ring inner pressure plate 6 are fitted together, and is fixed to the head end wall 1 by the main stage floating ring outer pressure plate 5 and the main stage floating ring inner pressure plate 6; there is a 1mm radial gap between the main stage floating ring 8 and the main stage floating ring outer pressure plate 5 and the main stage floating ring inner pressure plate 6, which is the floating gap of the floating ring; the annular protrusion 19 and the main stage floating ring 8 are fitted together to fix the porous evaporator tube 11 and the head end wall 1; there is a 0.1mm gap between the annular protrusion 19 and the main stage floating ring 8, which limits the flow area between the porous evaporator tube 11 and the main stage floating ring 8, and prevents excess gas from entering the flame tube.

[0052] This invention relates to a multi-nozzle, perforated evaporator-type fuel staged combustion chamber applied to the combustion chamber of a ship's gas turbine, which has three fuel supply modes: during startup and idle conditions, only the duty nozzle structure supplies fuel; as the operating conditions continue to increase, the duty nozzle structure and the auxiliary main combustion stage nozzle structure supply fuel; and as the operating conditions continue to increase, the duty nozzle structure, the auxiliary main combustion stage nozzle structure, and the main combustion stage nozzle structure all supply fuel.

[0053] The centrally located duty nozzle structure employs a centrifugal nozzle combined with a two-stage axial counter-rotating vortex cup and a three-stage progressive eccentric air inlet expansion and confinement domain structure to isolate the duty flame from the main combustion stage cold air, preventing the cold airflow from the main combustion stage nozzle structure from quenching the duty flame.

[0054] The duty nozzle structure employs a centrifugal nozzle combined with a two-stage axial counter-swirling cyclone and a three-stage progressive eccentric air inlet expansion and confinement zone. Air, under the action of the first-stage cyclone, the second-stage cyclone, and the cyclone cup sleeve, forms a strong backflow zone. The oil mist ejected from the centrifugal nozzle forms an oil film on the inner wall of the contraction guide channel of the second-stage cyclone. The oil film and droplets in the contraction guide channel are further broken up by the two counter-rotating airflows provided by the first and second-stage cyclones, and quickly mixed with air, forming an oil-rich gas-oil mixture inside the cyclone cup sleeve. This keeps the root of the duty flame continuously oil-rich. With the supplemental air from the three-stage progressive eccentric air inlet, the equivalence ratio of the duty flame gradually decreases downstream, making combustion more stable and beneficial for reducing NO. x The generation of .

[0055] This invention employs a premixed, pre-evaporated porous evaporator tube as the fuel-air mixing structure for the main combustion stage nozzle. A three-stage intake mode is used: the first stage uses an oblique-hole intake, guiding the airflow to the fuel-air mixing region through a guide channel; the shearing effect of the counter-swirling airflow from the first and second stage intakes rapidly mixes the fuel and air ejected from the centrifugal nozzle; the third stage uses a straight-hole airflow with a high momentum ratio (penetration depth), enabling even faster and more effective mixing of fuel and air within the fuel-air mixing region. Under the combined action of these three airflows, completely evaporated fuel droplets form at the guide channel outlet; the uniformly mixed fuel-air mixture results in a lean, premixed flame for the main combustion stage, leading to a more uniform combustion zone temperature and contributing to NO reduction. x generate.

[0056] Conventional multi-nozzle low-emission combustors have a lean fuel-air ratio of 0.005 at idle, while the porous evaporator-type fuel-stage multi-nozzle combustor of this invention, verified in high-temperature and high-pressure combustion bench tests, achieves a lean fuel-air ratio of 0.001 at idle, significantly improving idle lean fuel-air performance. NO under design conditions... x Emissions are below 50 ppm, achieving excellent low-emission performance.

[0057] By adjusting the length and diameter of the porous tube, the residence time of fuel within it can be controlled, ensuring complete evaporation without spontaneous combustion. Furthermore, due to the high axial velocity of the air entering the porous tube, the shearing action between the two counter-swirling airflows results in a significantly lower tangential velocity at the outlet than the axial velocity. This tangential velocity component at the outlet can be approximated as negligible. Consequently, the expansion angle of the main combustion flame is smaller, and the interaction area between the main combustion flame and the standby flame is also smaller, which is beneficial for further reducing NOx emissions. x The generation of .

[0058] In addition, since the diameter of the porous evaporator tube is much smaller than that of the conventional cyclone structure, the requirements for the head height are not high, and it can be applied in the compact casing space of the combustion chamber of the gas turbine in active ships.

[0059] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0060] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A porous evaporator-type fuel staged multi-nozzle combustion chamber, characterized in that, It includes a head end wall (1), an oil supply assembly and a flame tube (7); the oil supply outlet of the oil supply assembly is flush with one end of the head end wall (1); the front end of the flame tube (7) is fixedly connected to the other end of the head end wall (1). The head end wall (1) is provided with a plurality of main stage mounting holes and a duty officer mounting hole corresponding one-to-one with the oil supply component. The duty officer mounting hole is located at the center of the head end wall (1), and the plurality of main stage mounting holes are arranged in a ring around the duty officer mounting hole. The fuel supply assembly includes a duty nozzle structure (2), multiple auxiliary combustion nozzle structures (3) and multiple main combustion nozzle structures (4). The duty nozzle structure (2) is connected to the duty mounting hole, and the multiple auxiliary combustion nozzle structures (3) and multiple main combustion nozzle structures (4) are arranged in a ring to correspond to the main stage mounting hole. The oil outlet at one end of the duty nozzle structure (2) is welded to the head end wall (1); the duty nozzle structure (2) includes a second centrifugal nozzle (13), a first-stage cyclone separator (14), a second-stage cyclone separator (15), a cyclone cup sleeve (16), a duty cyclone separator cover plate (17), and a confinement area (18); the first-stage cyclone separator (14), the second-stage cyclone separator (15), and the cyclone cup sleeve (16) are integrally formed; the first-stage cyclone separator (14) has a through hole in the middle, which is fixed to the second centrifugal nozzle (13); the cyclone cup sleeve (16) and the confinement area (18) are fixedly connected through the duty cyclone separator cover plate (17); the outer wall of the end of the confinement area (18) is stepped, and the side of the stepped outer wall is provided with a three-stage progressive eccentric air inlet, the opening direction of which is at a certain angle to the radial direction; a number of uniformly arranged cooling holes are provided downstream of the three-stage progressive eccentric air inlet of the confinement area (18); The cyclone cup sleeve (16) has a boss at one end, and the front end of the limiting area (18) has a groove. The boss is embedded in the groove. The duty cyclone cover plate (17) is bolted to the limiting area (18) to fix the cyclone cup sleeve (16) and the limiting area (18). The auxiliary combustion nozzle structure (3), the main combustion nozzle structure (4), and the head end wall (1) are connected by a connecting structure; The connection structure includes a main stage floating ring outer pressure plate (5), a main stage floating ring inner pressure plate (6), and a main stage floating ring (8); the head end wall (1) is fixedly connected to the main stage floating ring outer pressure plate (5) and the head end wall (1) is fixedly connected to the main stage floating ring inner pressure plate (6); the main stage floating ring outer pressure plate (5) has a hole groove in the center that matches the main stage mounting hole, and the main stage floating ring inner pressure plate (6) has a hole groove on its outer edge that matches the main stage mounting hole; the main stage floating ring (8) The porous evaporator tube (11) is installed in the slot after the main floating ring outer pressure plate (5) and the main floating ring inner pressure plate (6) are fitted together, and is fixed to the head end wall (1) by the main floating ring outer pressure plate (5) and the main floating ring inner pressure plate (6); the porous evaporator tube (11) has an annular protrusion (19) on the end wall away from the oil inlet; the annular protrusion (19) and the main floating ring (8) are fitted together to fix the porous evaporator tube (11) and the head end wall (1) with a clearance fit. The head end wall (1) is provided with a groove at the center that matches the outer diameter of the outer pressure plate (5) of the main floating ring. Two cylindrical protrusions (20) are provided between the main mounting holes. The holes and grooves of the outer pressure plate (5) of the main floating ring are provided with through holes with the same diameter as the outer ring protrusions. The holes and grooves of the inner pressure plate (6) of the main floating ring are provided with through holes with the same diameter as the inner ring protrusions. The outer pressure plate (5) of the main floating ring and the inner pressure plate (6) of the main floating ring are embedded in the head end wall (1). The protrusions (20) cooperate with the through holes and are fixed to the protrusions (20) by bolts.

2. The porous evaporator tube type fuel staged multi-nozzle combustion chamber according to claim 1, characterized in that, The fuel supply assembly includes a duty nozzle structure (2), three auxiliary combustion nozzle structures (3) and six main combustion nozzle structures (4). The head end wall (1) is provided with nine main stage mounting holes and one duty nozzle mounting hole corresponding to the fuel supply assembly. The duty nozzle mounting hole is located at the center of the head end wall (1), and the nine main stage mounting holes are arranged in a ring around the duty nozzle mounting hole. The three auxiliary combustion nozzle structures (3) and the six main combustion nozzle structures (4) are arranged in a ring corresponding to the main stage mounting holes, and each auxiliary combustion nozzle structure (3) is dispersed between two main combustion nozzle structures (4).

3. The porous evaporator tube type fuel staged multi-nozzle combustion chamber according to claim 2, characterized in that, The auxiliary combustion nozzle structure (3) and the main combustion nozzle structure (4) have the same internal structure; the auxiliary combustion nozzle structure (3) includes a porous evaporator (11), an oil inlet pipe (9) and a first centrifugal nozzle (12); the outside of the oil inlet pipe (9) is threaded to the porous evaporator (11); the inside of the oil inlet pipe (9) is threaded to the first centrifugal nozzle (12); the wall of the porous evaporator (11) is provided with three levels of air inlets in sequence, the first two levels of air inlets are oblique holes in opposite directions, and the third level of air inlets are straight holes; the inside of the porous evaporator (11) is provided with a flow guide channel.

4. The porous evaporator tube type fuel staged multi-nozzle combustion chamber according to claim 3, characterized in that, The oil inlet pipe (9) is connected to the porous evaporator pipe (11) at one end in a stepped shape, and the step of the oil inlet pipe (9) is sealed to the porous evaporator pipe (11) by a copper gasket (10).

5. The porous evaporator tube type fuel staged multi-nozzle combustion chamber according to claim 2, characterized in that, Cooling holes are evenly provided around the main mounting hole and the duty mounting hole for cooling the side of the head end wall (1) that contacts the flame.

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