Annular combustion chamber and engine

Abstract

The application relates to the technical field of engines and discloses an annular combustion chamber and an engine, which comprise an outer casing assembly, an inner casing assembly and a fuel nozzle; a flame tube comprising a head, an outer ring, an inner ring and an air inlet sleeve provided on the outer ring; the outer ring and the inner ring are respectively provided with main combustion holes; an evaporation cavity is provided with an air inlet hole, the outlet of the fuel nozzle is communicated with the evaporation cavity, and the evaporation cavity is arranged outside the air inlet sleeve and between the outer casing assembly and the inner casing assembly. The fuel entering the evaporation cavity from the fuel nozzle is mixed with high-pressure air entering through the air inlet hole to form an oil-gas mixture, the oil-gas mixture enters the inside of the flame tube through the air inlet sleeve, high-pressure air entering the flame tube forms a large annular vortex at the head together with the oil-gas mixture, and high-temperature gas is formed by combustion, the high-temperature gas rotates along the circumference under the action of circumferential aerodynamic force of the air inlet sleeve, the circumferential temperature uniformity of the annular combustion chamber is effectively improved, local overheating is reduced, and carbon deposition and ablation are avoided.

Description

Technical Field

[0001] This invention relates to the field of engine technology, and more specifically to an annular combustion chamber and an engine. Background Technology

[0002] Small and medium-sized aero-engines typically use annular recirculation combustion chambers. The fuel atomization quality inside the evaporator tube of the annular combustion chamber is poor, and the fuel-air mixture at the evaporator tube outlet cannot be evenly distributed in the combustion chamber, causing local overheating and making it easy to accumulate carbon and burn. Summary of the Invention

[0003] In view of this, the present invention provides an annular combustion chamber and engine to solve the problems of uneven oil and gas distribution in the annular combustion chamber, which easily leads to carbon buildup and erosion.

[0004] In a first aspect, the present invention provides an annular combustion chamber, comprising: An outer casing assembly, an inner casing assembly, and a fuel nozzle disposed on the outer casing assembly; A flame tube includes a head, an outer ring, an inner ring, and an air inlet sleeve. The air inlet sleeve is disposed on the outer ring and is adapted to provide circumferential aerodynamic force. The outer ring and the inner ring are respectively provided with a first main combustion port and a second main combustion port for high-pressure air to enter the flame tube. The evaporation chamber is provided with an air inlet. The outlet of the fuel nozzle is connected to the evaporation chamber. The evaporation chamber is connected to the outside of the air inlet sleeve and is located between the outer casing assembly and the inner casing assembly.

[0005] Beneficial effects: Fuel entering the evaporation chamber through the fuel nozzle mixes with high-pressure air entering through at least the intake port to form a fuel-air mixture. Since the high-pressure air entering through the intake port has sufficient penetration depth, it improves the initial atomization effect of the fuel. The fuel-air mixture then enters the interior of the flame tube through the intake sleeve. This fuel-air mixture, together with the high-pressure air entering the flame tube through the main combustion holes on the outer and inner rings, forms a large annular vortex at the head and burns to form high-temperature gas. The high-temperature gas rotates circumferentially under the action of circumferential aerodynamic force in the intake sleeve, effectively improving the circumferential temperature uniformity of the annular combustion chamber, reducing local overheating, and avoiding carbon deposits and ablation.

[0006] In one optional embodiment, the outer ring and the inner ring are respectively provided with a first mixing hole and a second mixing hole for providing radial aerodynamic force.

[0007] Beneficial effects: By opening a first mixing hole and a second mixing hole on the outer ring and inner ring respectively, high-pressure air with radial aerodynamic force can be introduced. The airflow passes radially inward through the first mixing hole of the outer ring and radially outward through the second mixing hole of the inner ring, ensuring thorough mixing of the high-temperature combustion gas in the flame tube in the radial direction, effectively improving the radial temperature distribution uniformity of the outlet airflow. Combined with the improvement in circumferential temperature uniformity under the circumferential aerodynamic force of the intake sleeve, the combustion chamber outlet airflow simultaneously possesses excellent circumferential and radial temperature uniformity, effectively reducing the temperature gradient, avoiding localized high-temperature erosion, providing high-temperature combustion gas with a uniform temperature field for subsequent turbine components, optimizing the internal temperature field distribution of the combustion chamber, improving combustion efficiency, extending the service life of the combustion chamber, and improving engine reliability.

[0008] In one optional embodiment, the evaporation chamber includes: The cavity, wherein the air inlet is disposed in the cavity; A partition is disposed in the cavity, which divides the evaporation space between the cavity and the flame tube into multiple independent evaporation chambers.

[0009] Beneficial effects: By setting baffles in the evaporation chamber, the evaporation space is divided into multiple independent evaporation chambers, which allows the fuel-air mixture to flow in an orderly manner within the independent evaporation chambers. This prolongs the contact time between fuel and air, promotes further atomization and evaporation of fuel, improves the uniformity of fuel-air mixture, avoids uneven local fuel-air concentration, and is conducive to achieving stable, complete and uniform combustion, thereby improving the overall working performance of the combustion chamber.

[0010] In one optional embodiment, the evaporation chamber further includes: A cyclone separator is disposed in the cavity, and the fuel nozzle extends into the evaporation chamber through the cyclone separator.

[0011] Beneficial effects: By installing a swirler inside the cavity, the fuel nozzle extends into the evaporation chamber through the swirler, causing the high-pressure air entering the evaporation chamber to form a swirling flow. This enhances the turbulent mixing effect between fuel and air. Because the high-pressure air entering through the swirler has sufficient turbulence and the high-pressure air entering through the air intake has sufficient penetration depth, the initial atomization effect of the fuel is further improved, enhancing fuel atomization and evaporation efficiency. This results in a more uniform fuel-air mixture, ensuring more complete and stable combustion and reducing the risk of carbon buildup caused by incomplete combustion.

[0012] In one optional embodiment, the cavity is provided with a plurality of mounting holes spaced apart on its periphery, and the cyclone separator is disposed in the mounting holes.

[0013] Beneficial effects: By setting multiple mounting holes at intervals around the cavity to arrange the cyclone separators, the uniform arrangement and stable installation of the cyclone separators can be achieved, ensuring that the cyclone intensity of the intake air in each evaporation chamber is consistent, further improving the uniformity of fuel atomization, evaporation and mixing, avoiding local combustion abnormalities caused by uneven airflow distribution, and helping to improve the working stability and temperature field uniformity of the combustion chamber.

[0014] In one alternative embodiment, a plurality of the air inlets are disposed around the periphery of the mounting hole.

[0015] Beneficial effects: Arranging multiple air intake holes around the mounting holes allows for a more uniform distribution of high-pressure air entering the evaporation chamber, which is better matched with the swirling airflow formed by the cyclone separator. This enhances the overall mixing effect of air and fuel, avoids local airflow turbulence or uneven fuel-air concentration, and further improves atomization evaporation efficiency and combustion stability.

[0016] In one optional embodiment, the baffle is tile-shaped and fastened to the outer ring. In the circumferential direction of the annular combustion chamber, one end of the baffle abuts against the outer ring and corresponds to the intake sleeve, and the other end of the baffle extends circumferentially and forms an opening between it and the outer ring. The opening corresponds to the fuel nozzle, so that the fuel sprayed by the fuel nozzle mixes with the air entering through the intake port and flows along the evaporation chamber between the baffle and the flame tube to the intake sleeve.

[0017] Beneficial effects: The circumferentially oriented opening precisely corresponds to the fuel nozzle, guiding the fuel injected from the nozzle to quickly enter the evaporation chamber and fully mix with the high-pressure air entering from the air intake. Combined with the guiding effect of the tile-shaped baffles, the fuel-air mixture flows orderly along the evaporation chamber to the intake sleeve, further extending the contact path and time between fuel and air, promoting full fuel atomization and evaporation, improving the uniformity of fuel-air mixing, further optimizing the circumferential temperature uniformity of the annular combustion chamber, reducing local overheating, effectively avoiding carbon deposits and flame tube erosion, while improving fuel combustion efficiency and enhancing the overall operational reliability and service life of the annular combustion chamber.

[0018] In one alternative embodiment, cooling holes are provided on the head and / or the outer ring.

[0019] Beneficial effects: By opening cooling holes on the head and / or outer ring, high-pressure cooling air can be introduced to effectively cool the head and outer ring area of ​​the flame tube, reduce the working temperature of the flame tube wall, avoid local overheating and erosion, and improve the structural reliability and service life of the flame tube.

[0020] In one alternative embodiment, the air intake sleeve is arranged at an angle toward the head.

[0021] Beneficial effects: The intake manifold is arranged at an angle towards the head, so that the intake and exhaust are not in the same circumferential position, which effectively prolongs the residence time of the gas in the combustion zone, promotes complete combustion of fuel, and further optimizes the temperature field distribution in the combustion chamber.

[0022] In a second aspect, the present invention also provides an engine comprising the annular combustion chamber described in any of the preceding claims.

[0023] Beneficial effects: Since the engine includes the annular combustion chamber of the present invention, it has the same technical effects as the annular combustion chamber, which will not be described in detail here. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a cross-sectional view of an annular combustion chamber according to an embodiment of the present invention; Figure 2 This is a structural diagram of a flame tube according to an embodiment of the present invention; Figure 3 This is a cross-sectional view of an evaporation chamber according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of an evaporation chamber according to an embodiment of the present invention; Figure 5 for Figure 1 A schematic diagram of the fluid movement path in the annular combustion chamber shown. Figure 6 for Figure 1 A schematic diagram of the fluid motion path from another perspective of the annular combustion chamber shown. Figure 7 for Figure 6 A magnified view of the local structure; Figure 8 This is a three-dimensional structural diagram of an evaporation chamber according to an embodiment of the present invention; Figure 9 This is a three-dimensional structural diagram of a flame tube according to an embodiment of the present invention; Figure 10 This is a three-dimensional structural diagram of an annular combustion chamber according to an embodiment of the present invention; Figure 11 This is a three-dimensional structural diagram of an outer ring according to an embodiment of the present invention; Figure 12 This is a perspective view of the connection structure between a flame tube and a partition plate according to an embodiment of the present invention; Figure 13 This is a side view of the connection structure between the flame tube and the partition plate according to an embodiment of the present invention; Figure 14 This is a perspective view of the connection structure of the gas nozzle, baffle, and flame tube according to an embodiment of the present invention.

[0026] Explanation of reference numerals in the attached figures: 10. Outer casing assembly; 11. Front flange of outer casing; 12. Nozzle mounting base; 13. Rear flange of outer casing; 20. Inner casing assembly; 30. Flame tube; 31. Head; 32. Outer ring; 33. Inner ring; 34. Intake sleeve; 35. First main combustion port; 36. First mixing port; 37. Second main combustion port; 38. Second mixing port; 39. Cooling port; 40. Evaporation chamber; 41. Cavity; 42. Cyclone separator; 43. Baffle plate; 44. Air inlet; 45. Evaporation chamber; 46. Mounting hole; 50. Diffuser assembly; 60. Fuel injector; 70. Fuel main; 100. Large vortex. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.

[0028] In the description of the invention, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head 31," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0030] In related technologies, small and medium-sized aero-engine combustors typically employ annular recirculation combustors. The large annular vortex formed throughout the circumference of the combustor stabilizes the flame and organizes combustion. The large annular vortex field thoroughly mixes the fuel-air mixture entering from different nozzles through circumferential flow, promoting fuel atomization and fuel-air mixing. Each nozzle in the annular recirculation combustor is equipped with a swirler. The annular recirculation combustor utilizes multi-stage swirlers to generate multiple independent swirles throughout the circumference of the combustor, and uses the structure of the multi-stage swirlers to stabilize and organize combustion. The nozzles atomize liquid fuel, further atomizing the tiny droplets under the action of the swirling flow. After entering the flame tube, the fuel rapidly evaporates under the action of the igniter and mixes with air for combustion. Annular recirculation combustors typically use direct-injection nozzles or centrifugal nozzles for fuel supply. Direct-injection nozzles have a relatively simple structure and are usually matched with a single fuel line manifold. Their fuel atomization effect is poor and their ignition height is limited. Centrifugal nozzles have good atomization performance and can improve ignition capability. However, centrifugal nozzles are expensive, difficult to manufacture, and have complex processes. Moreover, the nozzle orifice size is precise. After long-term exposure to high temperatures, even a slight deformation of the orifice size will greatly affect the orifice performance.

[0031] Compared to conventional direct-injection or centrifugal-injection annular recirculation combustion chambers, the significant advantages of annular recirculation combustion chambers with evaporator tubes are lower design and manufacturing costs and relatively stable fuel atomization capabilities. The aerodynamic force of the air atomizes the fuel into droplets. The high-temperature combustion gas heats the fuel-air mixture inside the evaporator tube, which then enters the flame tube for evaporation and combustion. Conventional evaporator tubes are circular, with each tube paired with one fuel nozzle. Full-annular combustion chambers often use more than ten fuel nozzles, making the assembly, support, and positioning of the evaporator tubes and nozzles challenging. Evaporator tubes are typically distributed across the flame tube, with their inlets extending outwards from the flame tube and connecting to multiple nozzles on the fuel mains. Evaporator tube configurations include "crutch type," "T type," and "straight tube type," among others. As a fuel-aided atomization and fuel-air mixing device, the evaporator tube, in addition to compensating for the poor atomization quality of direct-injection nozzles, also heats air and liquid fuel, and mixes air and fuel vapors. However, the atomization and evaporation effect of the evaporator tube on fuel is always limited. This is mainly because the interaction between liquid fuel and air within the evaporator tube is not strong, the fuel is not sufficiently heated within the evaporator tube, and the turbulence intensity within the evaporator tube is insufficient. The fuel-air mixture at the evaporator tube outlet cannot be evenly distributed throughout the combustion chamber, resulting in localized combustion of the fuel-air mixture and causing localized overheating of the flame tube wall, leading to hot spots at the combustion chamber outlet. In view of this, the present invention is proposed.

[0032] The following is combined with Figures 1 to 14 The following describes embodiments of the present invention.

[0033] According to embodiments of the present invention, in one aspect, such as Figure 1 As shown, an annular combustion chamber is provided, comprising: The outer casing assembly 10, the inner casing assembly 20, and the fuel nozzle 60 disposed on the outer casing assembly 10; The flame tube 30 includes a head 31, an outer ring 32, an inner ring 33, and an air inlet sleeve 34. The air inlet sleeve 34 is disposed on the outer ring 32 and is adapted to provide circumferential aerodynamic force. The outer ring 32 and the inner ring 33 are respectively provided with a first main combustion port 35 and a second main combustion port 37 for high-pressure air to enter the flame tube 30. The evaporation chamber 40 is provided with an air inlet 44. The outlet of the fuel nozzle 60 is connected to the evaporation chamber 40. The evaporation chamber 40 is connected and disposed outside the air inlet sleeve 34 and located between the outer casing assembly 10 and the inner casing assembly 20.

[0034] Fuel entering the evaporation chamber 40 through the fuel nozzle 60 mixes with high-pressure air entering through at least the intake port 44 to form an oil-air mixture. Since the high-pressure air entering through the intake port 44 has sufficient penetration depth, the initial atomization effect of the fuel is improved. The oil-air mixture then enters the interior of the flame tube 30 through the intake sleeve 34. This oil-air mixture, together with the high-pressure air entering the flame tube 30 through the main combustion ports on the outer ring 32 and inner ring 33, forms a large annular vortex 100 at the head 31 and burns to form high-temperature gas. The high-temperature gas rotates circumferentially under the circumferential aerodynamic force of the intake sleeve 34, effectively improving the circumferential temperature uniformity of the annular combustion chamber, reducing local overheating, and avoiding carbon deposits and erosion.

[0035] Furthermore, the evaporator chamber 40 has a large radial width. Compared to the evaporator tubes in related technologies where airflow can only flow axially, the airflow can also flow radially, further increasing turbulence and improving atomization and fuel-air mixing. Better atomization results in smaller fuel particle diameters, leading to a larger surface area exposed to oxygen during combustion and easier complete combustion. In aircraft engines with low airflow, air impacts the fuel; however, due to surface tension, insufficient airflow prevents proper fuel dispersion, resulting in ignition failure. This invention, through the design of the evaporator chamber 40, effectively improves atomization and solves the problem of ignition failure at low airflow rates.

[0036] In some embodiments, see Figure 2 The outer ring 32 and the inner ring 33 are respectively provided with a first mixing hole 36 and a second mixing hole 38 for providing radial aerodynamic force.

[0037] By opening a first mixing hole 36 and a second mixing hole 38 on the outer ring 32 and inner ring 33 respectively, high-pressure air with radial aerodynamic force can be introduced. The airflow passes radially inward through the first mixing hole 36 of the outer ring 32, and radially outward through the second mixing hole 38 of the inner ring 33, so that the high-temperature gas in the flame tube 30 is fully mixed in the radial direction, effectively improving the radial temperature distribution uniformity of the outlet airflow. Combined with the improvement of circumferential temperature uniformity under the circumferential aerodynamic force of the intake sleeve 34, the outlet airflow of the combustion chamber has excellent circumferential and radial temperature uniformity at the same time, effectively reducing the temperature gradient, avoiding local high-temperature erosion, providing high-temperature gas with a uniform temperature field for subsequent turbine components, optimizing the internal temperature field distribution of the combustion chamber, improving combustion efficiency, extending the service life of the combustion chamber, and improving the reliability of engine operation.

[0038] It should be noted that the radial aerodynamic force here refers to the aerodynamic force along the radial direction of the flame tube 30.

[0039] In some embodiments, see Figure 3 and Figure 4 The evaporation chamber 40 includes: Cavity 41, wherein the air inlet 44 is disposed in cavity 41; A partition 43 is disposed in the cavity 41, and the partition 43 divides the evaporation space between the cavity 41 and the flame tube 30 into multiple independent evaporation chambers 45.

[0040] By setting a baffle 43 in the cavity 41 of the evaporation chamber 40, the evaporation space is divided into multiple independent evaporation chambers 45, which allows the fuel-air mixture to flow in an orderly manner in the independent evaporation chambers 45, prolonging the contact time between fuel and air. The long airflow path promotes further atomization and evaporation of fuel, improves the uniformity of fuel-air mixture, avoids uneven local fuel-air concentration, and is conducive to achieving stable, complete and uniform combustion, thus improving the overall working performance of the combustion chamber.

[0041] In some embodiments, see Figures 3-5 and Figure 8 The evaporation chamber 40 further includes: A cyclone separator 42 is disposed in the cavity 41, and the fuel nozzle 60 extends into the evaporation chamber 45 through the cyclone separator 42.

[0042] A swirler 42 is installed inside the cavity 41. The fuel nozzle 60 extends into the evaporation chamber 45 through the swirler 42, which can cause the high-pressure air entering the evaporation chamber 45 to form a swirling flow, enhancing the turbulent mixing effect of fuel and air. Since the high-pressure air entering the swirler 42 has sufficient turbulence and the high-pressure air entering the air intake 44 has sufficient penetration depth, the initial atomization effect of the fuel is further improved, the fuel atomization and evaporation efficiency is enhanced, the fuel-air mixture is more uniform, the combustion is more complete and stable, and the risk of carbon deposits caused by incomplete combustion is reduced.

[0043] Based on the vertical air intake vent 44, the addition of a cyclone separator 42 increases the swirling airflow and enhances the oil-air mixing effect. The evaporation chamber 40 with a cyclone separator 42 in this invention has a better atomization effect than a standalone cyclone separator 42 in related technologies. This is because a standalone cyclone separator 42 can only swirl along its axial direction, while the evaporation chamber 40 with a cyclone separator 42 in this invention... Figure 6 The swirling flow indicated by the yellow arrow in the middle extends the mixing path, resulting in better atomization.

[0044] In some embodiments, see Figure 4 and Figure 11 The cavity 41 is provided with a plurality of mounting holes 46 at intervals on its periphery, and the hydrocyclone 42 is disposed in the mounting holes 46.

[0045] By setting multiple mounting holes 46 at intervals around the cavity 41 to arrange the swirlers 42, the swirlers 42 can be evenly arranged and stably installed, ensuring that the intake swirling intensity of each evaporation chamber 45 is consistent, further improving the uniformity of fuel atomization, evaporation and mixing, avoiding local combustion abnormalities caused by uneven airflow distribution, and helping to improve the working stability and temperature field uniformity of the combustion chamber.

[0046] In some embodiments, such as Figure 4 As shown, a plurality of air inlets 44 are disposed around the mounting holes 46.

[0047] Arranging multiple air inlets 44 around the mounting holes 46 allows for a more uniform distribution of high-pressure air entering the evaporation chamber 40, which is reasonably matched with the swirling airflow formed by the swirler 42. This enhances the overall mixing effect of air and fuel, avoids local airflow turbulence or uneven fuel-air concentration, and further improves atomization evaporation efficiency and combustion stability.

[0048] In some embodiments, the baffle 43 is tile-shaped and fastened to the outer ring 32. In the circumferential direction of the annular combustion chamber, one end of the baffle 43 abuts against the outer ring 32 and corresponds to the intake sleeve 34. The other end of the baffle 43 extends circumferentially and forms an opening between it and the outer ring 32. The opening corresponds to the fuel nozzle 60, so that the fuel sprayed by the fuel nozzle 60 is mixed with the air entering through the intake port 44 and flows along the evaporation chamber 45 between the baffle 43 and the flame tube 30 to the intake sleeve 34.

[0049] The circumferentially oriented opening precisely corresponds to the fuel nozzle 60, guiding the fuel injected by the fuel nozzle 60 to quickly enter the evaporation chamber 45. This allows for thorough contact and mixing with the high-pressure air entering from at least the air intake port 44. Combined with the guiding effect of the tile-shaped baffle 43, the fuel-air mixture flows orderly along the evaporation chamber 45 towards the air intake sleeve 34. This further extends the contact path and time between the fuel and air, promoting full fuel atomization and evaporation, improving the uniformity of the fuel-air mixture, further optimizing the circumferential temperature uniformity of the annular combustion chamber, reducing local overheating, effectively preventing carbon deposits and flame tube 30 erosion, while also improving fuel combustion efficiency and enhancing the overall operational reliability and service life of the annular combustion chamber.

[0050] See Figure 6 , Figure 7 and Figure 14Multiple baffles 43 are spaced apart along the circumference of the outer ring 32. One end of each baffle 43 abuts against the outer ring 32 and corresponds to the first intake sleeve. The other end of each baffle 43 extends circumferentially and forms an opening between itself and the outer ring 32. Above the first intake sleeve is a first fuel nozzle, and the opening corresponds to a second fuel nozzle adjacent to the first fuel nozzle, thereby extending the atomization evaporation path and time.

[0051] In some embodiments, see Figure 2 Cooling holes 39 are provided on the head 31 and / or the outer ring 32.

[0052] By opening cooling holes 39 on the head 31 and / or outer ring 32, high-pressure cooling air can be introduced to effectively cool the head 31 and outer ring 32 areas of the flame tube 30, reduce the working temperature of the flame tube 30 wall, avoid local overheating and erosion, and improve the structural reliability and service life of the flame tube 30.

[0053] In some embodiments, see Figure 2 The air intake sleeve 34 is arranged at an angle toward the head 31.

[0054] The intake sleeve 34 is arranged at an angle toward the head 31, so that the intake and exhaust are not in the same circumferential position, which effectively prolongs the residence time of the gas in the combustion zone, promotes complete combustion of fuel, and further optimizes the temperature field distribution in the combustion chamber.

[0055] According to an embodiment of the present invention, another aspect provides an engine including an annular combustion chamber.

[0056] See Figures 1-13 This invention provides an aero-engine with an annular combustion chamber, which includes an outer casing assembly 10, an inner casing assembly 20, a flame tube 30, an evaporator chamber 40, a diffuser assembly 50, a fuel nozzle 60, and a fuel manifold 70. It should be noted that in this embodiment, the yellow arrows indicate the fuel flow direction, the blue arrows indicate the high-pressure air flow direction, and the red arrows indicate the large annular vortex 100.

[0057] The outer casing assembly 10 includes an outer casing front flange 11, a nozzle mounting seat 12, and an outer casing rear flange 13.

[0058] The flame tube 30 includes a head 31, an outer ring 32, an inner ring 33, an air inlet sleeve 34, a first main combustion hole 35, a first mixing hole 36, a second main combustion hole 37, a second mixing hole 38, and a cooling hole 39.

[0059] The evaporation chamber 40 includes a chamber 41, a cyclone separator 42, a baffle plate 43, and an air inlet 44.

[0060] The installation structure of the annular combustion chamber is as follows: The partition plate 43 of the evaporation chamber 40 is placed inside the chamber 41 and welded to the chamber 41. The chamber 41 has a mounting hole 46 for welding and mounting the cyclone separator 42.

[0061] The evaporation chamber 40 is installed outside the intake sleeve 34 of the flame tube 30, forming an evaporation space for fuel evaporation and mixing between the evaporation chamber 40 and the flame tube 30. The partition 43 can divide the evaporation space between the cavity 41 and the flame tube 30 into multiple individual evaporation chambers 45.

[0062] The outer casing rear flange 13 of the outer casing assembly 10 and the inner casing assembly 20 are fixed at the rear end with screws and nuts, and then the integrally mounted evaporation chamber 40 and flame tube 30 are placed in the area between the outer casing assembly 10 and the inner casing assembly 20.

[0063] The fuel nozzle 60 passes through the nozzle mounting base 12 and the swirler 42 from the outside to the inside, and is fixed to the nozzle mounting base 12 with screws.

[0064] The fuel main 70 is connected to all fuel nozzles 60 for supplying fuel.

[0065] The diffuser assembly 50 is located inside the front flange 11 of the outer casing and serves as the inlet for high-pressure air.

[0066] The aforementioned large annular vortex 100 and evaporator chamber 40 are combined in an annular combustion chamber. When the engine is operating, see [reference needed]. Figure 5 High-pressure air enters the combustion chamber through the passage between the diffuser assembly 50 and the front flange 11 of the outer casing. The fuel manifold 70 supplies fuel to all fuel nozzles 60, which in turn inject fuel into the evaporation chamber 40. The fuel entering the evaporation chamber 40 mixes with the high-pressure air entering through the swirler 42 and the intake port 44, forming a fuel-air mixture. The high-pressure air entering through the swirler 42 has sufficient turbulence, and the high-pressure air entering through the intake port 44 has sufficient penetration depth, effectively improving the initial atomization of the fuel. The fuel-air mixture flows along multiple individual evaporation chambers 45 formed between the baffles 43, further atomizing and evaporating, and finally is injected obliquely into the interior of the flame tube 30 from the intake sleeve 34.

[0067] The oil-gas mixture entering the flame tube 30 mixes with the high-pressure air entering the flame tube 30 through the first main combustion port 35 and the second main combustion port 37, forming a large annular vortex 100 at the head 31 and burning to form high-temperature gas. Under the circumferential aerodynamic force of the obliquely arranged intake sleeve 34, the high-temperature gas rotates circumferentially, which is beneficial for circumferential temperature uniformity. The high-temperature gas further mixes with the high-pressure air entering the flame tube 30 through the first mixing port 36 and the second mixing port 38 in the region between the outer ring 32 and the inner ring 33. This portion of high-pressure air has radial aerodynamic force, which is beneficial for radial temperature uniformity. Therefore, the high-temperature gas after mixing has good outlet circumferential temperature uniformity and outlet radial temperature uniformity, ensuring good power output when it enters the turbine.

[0068] It should be noted that for civil aviation turbojet and turbofan engines, the pressure of the high-pressure air introduced into the combustion chamber is generally in the range of 2MPa to 6MPa.

[0069] With the adoption of the annular combustion chamber of the present invention, the flame tube 30 and the evaporation tube can be integrated into a single design. The processing can be completed using conventional sheet metal stamping and welding technology. Compared with 3D printing or forging machining, the processing cost of the present invention is low, no secondary assembly is required, and the integrated design also facilitates assembly.

[0070] The intake sleeve 34 assists in forming a large annular vortex 100, which can solve the problem that the oil-gas mixture at the conventional evaporator outlet cannot be evenly distributed in the combustion chamber, causing hot spots at the outlet. It makes the atomized gas mixture evenly distributed in the circumference, which is beneficial to the uniformity of the high-temperature gas outlet temperature. This can not only ensure that the high-temperature gas does work normally, but also protect the turbine from high-temperature erosion.

[0071] This invention solves the problems of poor fuel atomization quality and uneven fuel-air mixing in conventional evaporator tubes by using an atomization and evaporation method with a fuel nozzle 60 and an evaporation chamber 40. It also addresses the issue that conventional centrifugal nozzles, which directly penetrate the flame tube 30 and come into contact with high-temperature combustion gases, suffer significant performance degradation from even slight nozzle size deformation due to prolonged exposure to high temperatures. Related technologies use nozzles with swirlers 42, resulting in straight airflow and short flow paths. However, with the baffle 43 and the inclined arrangement of the intake sleeve 34, the airflow streamline is longer, allowing for more thorough fuel-air mixing. This is particularly beneficial for small and medium-sized aero engines with small combustion chamber volumes, where the fuel-air mixing area cannot be too large. This invention, by incorporating an evaporation chamber 40, improves atomization through premixing and increased residence time while maintaining the same volume, enhancing outlet temperature uniformity and preventing localized high temperatures that could cause ablation.

[0072] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by this application.

Claims

1. An annular combustion chamber, characterized in that, include: The outer casing assembly (10), the inner casing assembly (20), and the fuel nozzle (60) disposed on the outer casing assembly (10). The flame tube (30) includes a head (31), an outer ring (32), an inner ring (33), and an air inlet sleeve (34). The air inlet sleeve (34) is disposed on the outer ring (32) and is adapted to provide circumferential aerodynamic force. The outer ring (32) and the inner ring (33) are respectively provided with a first main combustion port (35) and a second main combustion port (37) for high-pressure air to enter the flame tube (30). The evaporation chamber (40) is provided with an air inlet (44). The outlet of the fuel nozzle (60) is connected to the evaporation chamber (40). The evaporation chamber (40) is connected to the outside of the air inlet sleeve (34) and located between the outer casing assembly (10) and the inner casing assembly (20).

2. The annular combustion chamber according to claim 1, characterized in that, The outer ring (32) and the inner ring (33) are respectively provided with a first mixing hole (36) and a second mixing hole (38) for providing radial aerodynamic force.

3. The annular combustion chamber according to claim 1, characterized in that, The evaporation chamber (40) includes: Cavity (41), the air inlet (44) is disposed in the cavity (41); A partition (43) is disposed in the cavity (41), and the multiple partitions (43) divide the evaporation space between the cavity (41) and the flame tube (30) into multiple independent evaporation chambers (45).

4. The annular combustion chamber according to claim 3, characterized in that, The evaporation chamber (40) further includes: A cyclone separator (42) is disposed in the cavity (41), and the fuel nozzle (60) extends through the cyclone separator (42) into the evaporation chamber (45).

5. The annular combustion chamber according to claim 4, characterized in that, The cavity (41) is provided with a plurality of mounting holes (46) spaced apart on its periphery, and the cyclone separator (42) is disposed in the mounting holes (46).

6. The annular combustion chamber according to claim 5, characterized in that, Multiple air inlets (44) are disposed around the mounting hole (46).

7. The annular combustion chamber according to claim 3, characterized in that, The partition (43) is tile-shaped and fastened to the outer ring (32). In the circumferential direction of the annular combustion chamber, one end of the partition (43) abuts against the outer ring (32) and corresponds to the intake sleeve (34). The other end of the partition (43) extends circumferentially and forms an opening between it and the outer ring (32). The opening corresponds to the fuel nozzle (60), so that the fuel sprayed by the fuel nozzle (60) is mixed with the air entering through the intake hole (44) and flows along the evaporation chamber (45) between the partition (43) and the flame tube (30) to the intake sleeve (34).

8. The annular combustion chamber according to claim 1, characterized in that, Cooling holes (39) are provided on the head (31) and / or the outer ring (32).

9. The annular combustion chamber according to any one of claims 1 to 8, characterized in that, The air intake sleeve (34) is arranged at an angle toward the head (31).

10. An engine, characterized in that, It includes the annular combustion chamber according to any one of claims 1 to 9.

Images