Swirler and combustion chamber

Abstract

The vortex generator is fixed on the adapter section of the combustion chamber head through a connecting piece, and comprises a ring-shaped main body, a first axial extension, a second axial extension, a stop boss and a cooling hole. The ring-shaped main body comprises radial lugs and a pair of anti-rotation bosses arranged on each radial lug. The anti-rotation bosses and the radial lugs form a U-shaped space for accommodating the connecting piece. The second axial extension is arranged on each axial side of the ring-shaped main body respectively. The stop boss is arranged on the outer circumferential side of the first axial extension. The cooling hole penetrates through the ring-shaped main body and is arranged circumferentially. The vortex generator has a better end face cooling effect. A combustion chamber is also provided.

Description

Technical Field

[0001] This invention relates to the field of aero-engines, and more specifically to the field of vortex generators in combustion chambers. Background Technology

[0002] The vortex mixer is an important component of the combustion chamber of an aero-engine, affecting the overall performance of the combustion chamber. The vortex mixer creates a swirling flow, forming a recirculation zone in the flame tube to stabilize the flame, improve fuel atomization, and promote the formation of combustible mixture.

[0003] With the development of high performance and high pressure ratios in advanced aero-engine combustors, engine pressure ratios are constantly increasing, cycle efficiency is continuously improving, and combustor inlet temperatures are also rising, exceeding 1000K. This causes the fuel nozzles to bear a significant thermal load under high-temperature airflow. Simultaneously, to prevent nozzle jamming and vortex generator due to differences in expansion between the nozzle, flame tube, and casing under thermal loads, modern aero-engine combustors design the vortex generator as a freely floating structure to adapt to the effects of varying deformation caused by different temperatures among components. Furthermore, the working environment of the combustor flame tube is becoming increasingly harsh. Since the nozzle and vortex generator tip directly bear the high-temperature and harsh environment, the vortex generator also faces a certain risk of ablation. Summary of the Invention

[0004] One object of the present invention is to provide a vortex generator that has a better end-face cooling effect.

[0005] To achieve the above objectives, the vortex generator is fixed to the combustion chamber head transition section via a connector. It includes an annular body, a first axial extension, a second axial extension, a top boss, and cooling holes. The annular body includes radial lugs and a pair of anti-rotation bosses disposed on each of the radial lugs. The anti-rotation bosses and the radial lugs form a U-shaped space, which is used to accommodate the connector. The second axial extension and the first axial extension are respectively disposed on both axial sides of the annular body. The top boss is disposed on the outer periphery of the first axial extension. The cooling holes penetrate the annular body and are circumferentially disposed.

[0006] In one or more embodiments, a circumferential channel is provided between the second axial extension and the annular body, and one end of the cooling hole is connected to the circumferential channel.

[0007] In one or more embodiments, the vortex generator further includes a plurality of swirling grooves disposed circumferentially distributed on the second axial extension.

[0008] In one or more embodiments, the swirl channel is a rectangular channel.

[0009] In one or more embodiments, the height of the abutment boss is greater than the radial height of the cooling hole.

[0010] In one or more embodiments, a pair of radial lugs are distributed on the upper and lower sides of the annular body.

[0011] In one or more embodiments, the outer diameter of the first axial extension is set to be smaller than the outer diameter of the second axial extension.

[0012] In one or more embodiments, the annular body includes a groove located at the outlet of the cooling hole.

[0013] In one or more embodiments, the abutting boss is disposed on the upper and lower sides of the first axial extension.

[0014] Another object of the present invention is to provide a combustion chamber comprising a head transition section, a fuel nozzle, a pressure plate, and the aforementioned swirl generator, wherein the U-shaped space of the swirl generator is connected to the head transition section via the pressure plate, and the fuel nozzle extends into the interior of the swirl generator and floats in cooperation with the swirl generator.

[0015] The aforementioned vortex generator effectively prevents circumferential rotation by setting a pair of anti-rotation bosses on the radial lugs. At the same time, by removing the lug structure on both sides, the influence of the lug structure on the air intake is avoided, so that there is no obstruction between adjacent vortices, providing an appropriate amount of uniform air to the head. The fixed top platform is located at the point where the vortex generator directly contacts the flame. After positioning, the cooling gas can smoothly pass through the small hole to cool the end face of the vortex generator, avoiding the effects of backfire or high temperature. Attached Figure Description

[0016] The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, wherein:

[0017] Figure 1 This is a cross-sectional view of the combustion chamber of an aircraft engine;

[0018] Figure 2 This is a schematic diagram of the connection structure between the vortex generator and the transition section at the head of the combustion chamber.

[0019] Figure 3 This is a schematic diagram of one embodiment of an eddy current generator;

[0020] Figure 4 This is a schematic diagram showing the connection relationship between the eddy current generator and the connecting parts;

[0021] Figure 5 This is a schematic diagram of the cooling holes;

[0022] Figure 6 This is a side view of the vortex generator;

[0023] Figure 7 yes Figure 6 A magnified view of point N in the middle. Detailed Implementation

[0024] The present invention will be further described below with reference to specific embodiments and accompanying drawings. More details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention can obviously be implemented in many other ways different from those described herein. Those skilled in the art can make similar extensions and derivations based on actual application situations without departing from the spirit of the present invention. Therefore, the scope of protection of the present invention should not be limited by the content of this specific embodiment.

[0025] It should be noted that these and other accompanying drawings are merely examples and are not drawn to scale, and should not be construed as limiting the scope of protection of the present invention.

[0026] Figure 1 A cross-sectional view of the combustion chamber of an aero-engine is shown, including components such as the outer ring of the flame tube 1, the fuel nozzle 2, the head transition section 3, the inner and outer caps 4, the inner ring of the flame tube 5, the outer casing of the combustion chamber 6, the front diffuser 7, and the vortex generator 8.

[0027] The vortex generator 8 is fixed to the head transition section 3 by two pressure plates, upper and lower. Each pressure plate is fixed to the head transition section and the inner and outer rings of the flame tube by bolts. Figure 1 The upper pressure plate 9 shown is fixed to the head adapter section 3 and the outer ring 1 of the flame tube by bolts. The vortex generator 8 is assembled by the axial clearance between the pressure plate and the head adapter section 3. The vortex generator 8 is set on the outer periphery of the tail of the fuel nozzle 2, so as to achieve free floating between it and the fuel nozzle 2.

[0028] like Figure 2 As shown, modern aero engines generally employ an annular combustion chamber. High-pressure gas exiting the compressor enters the combustion chamber and is mainly divided into three streams. The first stream directly enters the outer annular cavity channel of the combustion chamber to cool the outer ring of the flame tube and the ignition nozzle. The second stream directly enters the inner annular cavity channel of the combustion chamber to cool the inner ring of the flame tube. The third stream enters the combustion reaction chamber from the head of the combustion chamber and mixes thoroughly with the fuel. Under the action of the ignition nozzle, the mixture undergoes a violent chemical reaction and combustion to produce high-temperature combustion gas. With the development of modern technology, the working environment of the aero engine combustion chamber flame tube is becoming increasingly harsh. Because the front ends of the fuel nozzle 2 and the vortex generator 8 are directly subjected to the high-temperature and harsh environment, there is a certain risk of ablation.

[0029] Therefore, this application discloses a vortex generator that can move freely relative to the fuel nozzle without affecting the circumferential uniform gas volume. The vortex generator can withstand high temperature environments through some cooling methods and has the advantages of convenient processing and easy assembly and disassembly.

[0030] The vortex generator 8 is fixed to the combustion chamber head transition section 3 by a connector, which in some embodiments is the aforementioned pressure plate 9. The vortex generator 8 includes an annular body 810, a first axial extension 820, a second axial extension 830, a top boss 840, and a cooling hole 850.

[0031] like Figures 3 to 7 As shown, the annular body 810 includes radial lugs 811 and a pair of anti-rotation bosses 812 disposed on each radial lug 811. The anti-rotation bosses 812 and the radial lugs 811 form a U-shaped space 813. The U-shaped space 813 is used to accommodate connecting parts such as pressure plates. Figure 4 As shown.

[0032] In this way, within the U-shaped space 813 formed by the anti-rotation boss 812 and the radial lug 811, the pressure plate 9 has the anti-rotation boss 812 playing a circumferential limiting role, and directly achieving circumferential anti-rotation in cooperation with the pressure plate.

[0033] Preferably, the vortex generator 8 includes a pair of radial lugs 811, distributed on the upper and lower sides of the annular body 810, rather than the left and right sides. By removing the lug structures on the left and right sides, the influence of the lug structures on the intake volume is avoided, ensuring no obstruction between adjacent vortex generators and providing an appropriate amount of uniform air to the head. This ensures uniform mixing of the fuel injector main nozzle with the air, avoids disturbance, and reduces the risk of combustion oscillation. Simultaneously, removing the circumferential lug structures allows the vortex generator channels and U-shaped groove structures to be machined from bar stock. Compared to traditional casting methods, this avoids the impact of low initial casting yield and ensures that the mating parts, i.e., the boss structures, can be directly repaired by welding during rework, achieving convenient maintenance, shortening time, and exhibiting better economic performance.

[0034] The anti-rotation boss structure of this scheme only requires the design of one type of vortex generator to achieve its function, without the need for multiple types of main vortex generators to be used together.

[0035] To prevent the vortex generator from being affected by heat loads from tempering or high-temperature areas being too close to the head, cooling gas is designed on the inlet side of the vortex generator. The annular body 810 is also equipped with circumferentially distributed cooling holes 850, such as... Figure 5 and Figure 7 As shown, cooling air B flows through cooling holes 850 to the end face of the vortex generator, cooling the end face of the vortex generator. The circumferentially evenly arranged cooling holes 850 provide an appropriate amount of uniform air to the head to ensure uniform mixing of the fuel nozzle main nozzle and air, avoid disturbance, and reduce the risk of combustion oscillation.

[0036] like Figure 7 As shown, the annular body 810 also includes a groove 814 located at the outlet of the cooling hole 850 to guide the cooling gas B out.

[0037] Cooling holes 850 can be Figure 7 The straight hole shown can also be an angled hole. The length-to-diameter ratio of the groove 814 can also be adjusted according to actual cooling requirements.

[0038] The first axial extension portion 820 and the second axial extension portion 830 are respectively disposed on both sides of the annular body. Relatively, the first axial extension portion 820 is closer to the combustion chamber side, and the second axial extension portion 830 is farther away from the combustion chamber side.

[0039] The second axial extension 830 is provided with a plurality of circumferentially distributed swirl grooves 870 for providing head air intake C. The head air intake C cooperates with the nozzle fuel to generate a high-speed rotating jet at the head of the flame tube, forming a low-pressure zone, thereby creating a recirculation zone to ensure flame stability; and the high-speed rotating jet increases the relative velocity between the airflow and the fuel droplets, improving fuel atomization and air-fuel mixture formation.

[0040] The abutment boss 840 is located on the outer periphery of the first axial extension 820, at the point where the vortex generator directly contacts the flame, i.e., at the fuel nozzle outlet. Due to the different expansion amounts of the nozzle, flame tube, and casing caused by thermal loads, the nozzle and vortex generator are generally designed as free-floating structures. To prevent the vortex generator from being affected by backfire or the thermal load of the high-temperature area being too close to the head, a cooling gas B is designed on the vortex generator's inlet side; simultaneously, to prevent the cooling hole 850 from being blocked due to the free-floating vortex generator being affected by the nozzle during operation, the aforementioned abutment boss 840 is designed.

[0041] In some embodiments, the abutment boss 840 is disposed on the upper and lower sides of the first axial extension 820.

[0042] During normal operation of the nozzle, due to the thermal deformation of the nozzle and the flame tube, the nozzle drives the vortex generator to move upward relative to the flame tube, such as... Figure 2 The floating gap A is shown. The floating gap is the free float. The abutment boss 840 can abut against the head transition section 3 during overload of the eddy current movement, preventing the entire eddy current 8 from completely fitting with the head transition section 3 and blocking the entry of cooling air from the cooling hole 850. This ensures that after positioning, the cooling air can smoothly pass through the small hole to cool the end face of the eddy current, avoiding the effects of backfire or high temperature.

[0043] Therefore, in some embodiments, the height of the abutment boss 840 is greater than the radial height of the cooling hole 850, so that when the abutment boss 840 abuts the combustion chamber head transition section 3, there is still enough cooling space for the cooling gas.

[0044] In addition, the outer diameter of the first axial extension 8220 is set to be smaller than the outer diameter of the second axial extension 830. The second axial extension 830 and the annular body 810 also have a circumferential channel 860. One end of the cooling hole 850 is connected to the circumferential channel 860. Cooling gas B flows from the circumferential channel 860 to the cooling hole 850 and then to the end face of the first axial extension 820.

[0045] The aforementioned vortex generator features two anti-rotation bosses on the radial lugs fixed by the pressure plate, which prevent the vortex generator from rotating clockwise and counterclockwise in the circumferential direction. At the same time, the side lugs are eliminated to ensure the air intake volume. A top boss is also provided at the point where the vortex generator directly contacts the flame, which, together with the cooling holes, ensures that the cooling air can always smoothly cool the end face of the vortex generator, avoiding the effects of backfire or high temperature.

[0046] Based on the above description of the vortex generator, a combustion chamber including the aforementioned vortex generator can be understood. The head transition section 3 engages with the U-shaped space on the annular body 810 of the vortex generator via a pressure plate 9. The fuel nozzle 2 extends into the inner cavity 800 of the vortex generator 8 and floats in conjunction with the vortex generator 8. Therefore, the vortex generator can move freely without affecting the circumferential uniform air volume and also has better cooling performance to withstand the high-temperature environment of the combustion chamber.

[0047] It should be noted that the use of terms such as "first" and "second" to define the components in the above content is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application.

[0048] In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms 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 on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0049] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic related to at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0050] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any variations and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the invention, fall within the protection scope defined by the claims of the present invention.

Claims

1. A vortex generator, fixed to the transition section at the head of the combustion chamber by a connector, characterized in that, include: The annular body includes radial lugs and a pair of anti-rotation bosses disposed on each of the radial lugs. The anti-rotation bosses and the radial lugs form a U-shaped space, which is used to accommodate the connector. First axial extension; The second axial extension portion and the first axial extension portion are respectively disposed on both sides of the annular body; Abutting boss is disposed on the outer peripheral side of the first axial extension; and Cooling holes are provided throughout the annular body and are arranged circumferentially.

2. The eddy current generator as described in claim 1, characterized in that, The second axial extension has a circumferential channel between itself and the annular body, and one end of the cooling hole is connected to the circumferential channel.

3. The eddy current generator as described in claim 1, characterized in that, The vortex generator also includes a plurality of swirling grooves arranged circumferentially on the second axial extension.

4. The eddy current generator as described in claim 3, characterized in that, The vortex channel is a rectangular channel.

5. The eddy current generator as claimed in claim 1, characterized in that, The height of the abutment boss is greater than the radial height of the cooling hole.

6. The eddy current generator as claimed in claim 1, characterized in that, A pair of radial lugs are distributed on the upper and lower sides of the annular body.

7. The eddy current generator as claimed in claim 1, characterized in that, The outer diameter of the first axial extension is set to be smaller than the outer diameter of the second axial extension.

8. The eddy current generator as claimed in claim 1, characterized in that, The annular body includes a groove located at the outlet of the cooling hole.

9. The eddy current generator as claimed in claim 1, characterized in that, The abutting boss is provided on the upper and lower sides of the first axial extension.

10. A combustion chamber, characterized in that, include: The assembly includes a head adapter, a fuel injector, a pressure plate, and a vortex generator as described in any one of claims 1-9, wherein the U-shaped space of the vortex generator is connected to the head adapter via the pressure plate, and the fuel injector extends into the interior of the vortex generator and floats in cooperation with the vortex generator.

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