Combustion chamber interstage section structure, combustion chamber, aircraft engine

Abstract

The disclosure provides a combustion chamber inter-stage segment structure, the inter-stage segment is made of ceramic matrix composite material, comprising a first annular structure, a second annular structure and a supporting ring surface between the first annular structure and the second annular structure; a metal adapter segment comprises a connecting piece and a baffle, the connecting piece and the baffle are opposite to each other and define an annular groove for accommodating the second annular structure; an axial spring plate is arranged between the baffle and the inter-stage segment and located at the outer periphery of the supporting ring surface; a radial spring plate is located in the annular groove and arranged at the radial outside of the second annular structure; a fastener is used to fasten the connecting piece and the baffle and make the connecting piece and the baffle clamp the second annular structure. The structure enables the inter-stage segment of the ceramic matrix composite material to timely release the thermal deformation in the axial and radial directions and reduce the thermal stress. The disclosure also provides a combustion chamber and an aero-engine.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aero-engines, in particular to the field of combustion chamber CMC inter-stage section. BACKGROUND

[0002] With the development of aero-engine technology, the temperature before the engine turbine is continuously increasing, and the head of the combustion chamber of modern aero-engines generally adopts staged combustion technology. The nozzle inter-stage section is located between the main combustion stage and the pre-combustion stage of the combustion chamber, and the thermal load of the working environment will continue to increase. How to prevent the inter-stage section from ablation and make it serve safely for a long time is one of the main tests for the design of the combustion chamber of the aero-engine. The service life of the inter-stage section made of traditional high-temperature alloy or single crystal brings great challenges, and even after long-term service, the inter-stage section of the mature product will also have ablation. The safe use of the nozzle will be affected after the inter-stage section is ablated, so the inter-stage section also faces the problem of repair and replacement, so it is necessary to consider developing an inter-stage section structure of ceramic matrix composites (CMC) with higher temperature resistance.

[0003] Limited by the manufacturing process, CMC materials are currently mainly used in the inner and outer rings of the combustion chamber flame tube, turbine blades, etc., and cannot be used in a large range. Due to the low linear expansion coefficient of CMC materials, attention should be paid to the design and cooperation of the connection structure with other metal parts to avoid large internal stress caused by different expansion amounts under thermal state, thereby causing structural failure. In addition, the convenience of maintenance of the inter-stage section should also be considered. SUMMARY

[0004] An object of the present application is to provide a combustion chamber inter-stage section structure with better thermal deformation release effect.

[0005] To achieve the above-mentioned object, the combustion chamber inter-stage section structure comprises an inter-stage section, a metal adapter section, an axial spring, a radial spring and a fastener. The inter-stage section is made of ceramic matrix composite material and comprises a first annular structure, a second annular structure and a supporting ring surface located between the first annular structure and the second annular structure. The metal adapter section comprises a connecting piece and a baffle, and the connecting piece and the baffle face each other to define an annular groove for accommodating the second annular structure. The axial spring is arranged between the baffle and the inter-stage section and located at the outer periphery of the supporting ring surface. The radial spring is located in the annular groove and arranged radially outside the second annular structure. The fastener is used to fasten the connecting piece and the baffle and make the connecting piece and the baffle clamp the second annular structure.

[0006] In one or more embodiments, the fastener is detachably connected with the connecting piece and the baffle.

[0007] In one or more embodiments, the fastener penetrates the axial spring.

[0008] In one or more embodiments, the axial spring sheet comprises a radial cooling hole.

[0009] In one or more embodiments, the connecting piece is provided with a first axial cooling hole.

[0010] In one or more embodiments, the first axial cooling hole comprises an inner circle cooling hole facing the end face of the second ring structure and an impingement cooling hole facing the baffle.

[0011] In one or more embodiments, the baffle is provided with a second axial cooling hole aligned with the impingement cooling hole.

[0012] In one or more embodiments, the baffle comprises two semicircle ring structures spliced with each other.

[0013] In one or more embodiments, the axial spring sheet between the baffle and the inter-stage section is arranged in an axial pre-tightened state, and the radial spring sheet inside the annular groove and radially outside the second ring structure is arranged in a radial pre-tightened state.

[0014] Another object of the present application is to provide a combustion chamber comprising a flame tube, a fuel nozzle, a main combustion stage swirler, a pre-combustion stage swirler, the flame tube defining a combustion space, a plurality of the main combustion stage swirler arranged around the pre-combustion stage swirler, and the above-mentioned combustion chamber inter-stage section structure, the connecting piece of the combustion chamber inter-stage section structure being fixedly connected with the pre-combustion stage swirler, the first ring structure facing the combustion space.

[0015] In one or more embodiments, the connecting piece is welded on the pre-combustion stage swirler.

[0016] Still another object of the present application is to provide an aero-engine comprising the above-mentioned combustion chamber.

[0017] The above-mentioned inter-stage section structure adopts a combination of radial spring sheet structure and axial spring sheet structure, which ensures that the CMC inter-stage section can realize both radial floating and axial floating, so that the CMC inter-stage section can release thermal deformation, reduce thermal stress, and improve service life. The damping effect brought by the radial spring sheet structure and the axial spring sheet structure can reduce the radial vibration and axial vibration of the CMC inter-stage section during operation, thereby reducing the risk of vibration failure of the CMC inter-stage section. BRIEF DESCRIPTION OF DRAWINGS

[0018] The above-mentioned and other features, properties, and advantages of the present application will become more apparent by describing in the following the description of the drawings and embodiments, in which:

[0019] Figure 1 is a structural schematic diagram of an aero-engine combustion chamber.

[0020] Figure 2A This is a sectional view of the inter-stage structure;

[0021] Figure 2B yes Figure 2A Enlarged view of point C in the middle;

[0022] Figure 3 This is a side view of the inter-stage structure;

[0023] Figure 4 This is a schematic diagram of the cooling holes in the transition section;

[0024] Figure 5 This is a schematic diagram showing the breakdown of each component of the inter-stage structure. Detailed Implementation

[0025] 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.

[0026] 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.

[0027] Figure 1 The diagram shows a simplified structure of an aero-engine combustor, which includes a fuel nozzle 1, a pre-combustion stage swirler 3, a main combustion stage swirler 4, a flame tube 5, an interstage section 2, and an outer casing 6. The interstage section 2 is located outside the fuel nozzle 1, surrounded by two flames: premixed combustion formed downstream of the main combustion stage swirler 4 and diffusion combustion formed downstream of the pre-combustion stage swirler 3. Therefore, it generally suffers from high heat load, susceptibility to ablation, and significant challenges in thermal protection design.

[0028] Figures 2A to 5 The interstage structure described in this disclosure is shown, where X represents the axial direction and Y represents the radial direction. The interstage structure includes an interstage 23 made of ceramic matrix composite (CMC) material and a metal transition section, the metal transition section including a connector 21 and a baffle 22.

[0029] Reference Figure 5It is understood that the inter-stage section 23 comprises a first annular structure 231, a second annular structure 232, and a supporting annular surface 233 between the first annular structure 231 and the second annular structure 232. Preferably, the first annular structure 231 faces the combustion zone, and the outer diameter of the second annular structure 232 is smaller than that of the first annular structure 231.

[0030] The connecting member 21 and the baffle 22 are opposite to each other, defining an annular groove 235 for accommodating the second annular structure 232. In the embodiment shown in the drawings, the annular groove 235 is formed on the inner annular surface of the baffle 22. It is understood by those skilled in the art that in other embodiments, the axial groove surfaces on both sides of the annular groove 235 can be provided by the connecting member 21 and the baffle 22, respectively. Figure 2B and Figure 5 In the embodiment shown in the drawings, the annular groove 235 is formed on the inner annular surface of the baffle 22. It is understood by those skilled in the art that in other embodiments, the axial groove surfaces on both sides of the annular groove 235 can be provided by the connecting member 21 and the baffle 22, respectively.

[0031] In order to enable the CMC inter-stage section to release thermal deformation, the inter-stage section structure described in the present disclosure further comprises an axial spring 25 and a radial spring 26 to ensure that the CMC inter-stage section can simultaneously achieve axial floating and radial floating.

[0032] The axial spring 25 is arranged between the baffle 22 and the inter-stage section 23 and located at the outer periphery of the supporting annular surface 233, ensuring that the CMC inter-stage section 23 can axially float. The axial spring 25 should be pre-tensioned with a certain axial pre-tightening force during assembly, so that the axial spring 25 has a certain pressure in any working state, thereby achieving better sealing between the annular structure 232 and the end surface 236 of the annular groove 235.

[0033] The radial spring 26 is located inside the annular groove 235 and arranged radially outside the second annular structure 232, ensuring that the CMC inter-stage section 23 can radially float. The radial spring 26 should be pre-tensioned with a certain radial pre-tightening force during assembly, so that the radial spring 26 has a certain pressure in any working state, thereby achieving better sealing.

[0034] The fastener 24 is used to fasten the connecting member 21 and the baffle 22, and to clamp the second annular structure 232 with the connecting member 21 and the baffle 22. For example, the fastener 24 is a mounting bolt, and threaded holes 221 are provided on the mounting baffle 22, and the connecting member 21 and the metal mounting baffle 22 are fastened and connected through the mounting bolt.

[0035] In order to facilitate the maintenance and replacement of the inter-stage section 23, the fastener 24 detachably connects the connecting member 21 and the baffle 22.

[0036] In some embodiments, after the mounting bolt connects the metal connecting member 21 and the metal mounting baffle 22, it extends into the connecting hole 251 of the axial spring 25 to penetrate the axial spring 25 and limit the axial spring 25, avoiding the falling off of the axial spring 25.

[0037] Furthermore, the damping effect of the radial spring 26 and the axial spring 25 can reduce the radial and axial vibrations of the CMC stage segment 23 during operation, thereby reducing the risk of vibration failure of the CMC stage segment 23.

[0038] In some embodiments, the radial spring 26 and the axial spring 25 are high-temperature alloy and stainless steel springs.

[0039] Continue to refer to Figure 3 and Figure 4 As shown, a first axial cooling hole 211 is provided on the transition section 21. Furthermore, the first axial cooling hole 211 includes an inner ring cooling hole 2112 for cooling the clamped position of the CMC stage section 23 (i.e., the end face of the second annular structure 232) and an impact cooling hole 2113 facing the baffle 22. Relatively speaking, the inner ring cooling hole 2112 is located radially inward, and the impact cooling hole 2113 is located radially outward.

[0040] Specifically, the inner ring cooling hole 2112 is used to cool the end face of the CMC stage section 23 at the clamping position, that is... Figure 2B The left end face shown is located on one side of the gap 212 to prevent high-temperature gas from seeping into the gap 212 between the mounting baffle 22 and the CMC stage section 23. The inner ring cooling hole 2112 helps to reduce the temperature at the connection position and ensure the reliability of the connection structure.

[0041] The baffle 22 is also provided with a second axial cooling hole 222 aligned with the impact cooling hole 2113, such as Figure 5 As shown, it is used to guide the cooling air to reduce the wall temperature of the CMC stage section 23, thereby increasing the service life of the CMC stage section 23.

[0042] Continue to refer to Figure 5 As shown, the axial spring 25 includes radial cooling holes 252 for cooling the axial spring 25 and maintaining the reliability of the axial spring 25.

[0043] The metal baffle 22 is preferably composed of two interlocking semi-circular ring structures. During assembly, the radial spring 26 and axial spring 25 are first placed at the corresponding connection positions of the CMC stage section 23. Then, the two semi-circular ring structures of the metal baffle 22 are engaged with the second annular structure 232 of the CMC stage section 23. After adjusting the preload of the radial spring 26 and axial spring 25, the two semi-circular ring structures of the metal baffle 22 are closed. Multiple circumferential fasteners 24, such as mounting bolts, are used to connect the metal adapter section 21 to the metal baffle 22 through the threaded holes on the metal baffle 22. The mounting bolts are then tightened until they extend into the pre-set connection hole 251 of the axial spring 25. In this way, the fasteners 24 secure the connector 21 and the baffle 22, and the connector 21 and the baffle 22 clamp the second annular structure 232 of the stage section 23.

[0044] Preferably, a small gap is provided between the axial tail end of the mounting bolt and the inter-stage section 23 to allow the floating of the inter-stage section 23.

[0045] In some embodiments, the connecting hole 251 can be provided as a circular hole or an elliptical hole with a diameter larger than that of the fastener 24, so as to facilitate the alignment of the fastener with the position of the connecting hole 251 and improve the assembly convenience.

[0046] In this way, when the inter-stage section 23 needs to be repaired and replaced after long-term service, only the fastener 24 needs to be loosened, and the replaced or repaired inter-stage section 23 is reassembled, without the need for overall scrapping, greatly improving the convenience of repairing the inter-stage section 23 and significantly reducing the repair time and cost.

[0047] The above-mentioned combustion chamber inter-stage section structure adopts a combination of a radial spring structure and an axial spring structure, which ensures that the CMC inter-stage section can realize both radial floating and axial floating, thereby enabling the CMC inter-stage section to release thermal deformation, reduce thermal stress, and improve service life. The damping effect brought by the radial spring structure and the axial spring structure can also reduce the radial vibration and axial vibration of the CMC inter-stage section during operation, thereby reducing the risk of vibration failure of the CMC inter-stage section. The radial spring structure and the axial spring structure can also achieve better sealing by pre-setting a certain pre-tightening force.

[0048] In combination with the introduction of the above-mentioned inter-stage section connecting structure, it can also be understood that a combustion chamber and an aero-engine comprising the same.

[0049] The combustion chamber comprises a flame tube 5, a fuel nozzle 1, a main combustion stage swirler 4, a pre-combustion stage swirler 3, and the above-mentioned combustion chamber inter-stage section structure. The flame tube 5 defines a combustion space 501, and one or more main combustion stage swirlers 4 are arranged outside the pre-combustion stage swirler 3. Among them, the connecting piece 21 of the combustion chamber inter-stage section structure is fixedly connected with the pre-combustion stage swirler 3, such as being directly welded on the pre-combustion stage swirler 3.

[0050] It should be noted that the above content uses the words "first", "second", etc. to define parts, which is only for the convenience of distinguishing the corresponding parts, and the above words have no special meaning if there is no further declaration, and therefore cannot be understood as a limitation on the protection scope of the present application.

[0051] Also, certain terminology has been used in the description for the purpose of reference only. For example, the terms "one embodiment" and "some embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Therefore, it is emphasized and should be appreciated that every aspect included in the present description is not necessarily a separate embodiment. Further, the various characteristics or features described in one or more embodiments are applicable to other embodiments. Moreover, it is appreciated that many modifications can be made to the embodiments described above, and that the application can include any number of additional or different steps, components, or elements, and that the elements described herein can be replaced by other means or materials for the same function.

[0052] Although the present application has been disclosed in its preferred embodiments with reference to the accompanying drawings, it is to be understood that the application is not limited to those precise embodiments, and that changes and modifications can be effected therein by one of ordinary skill in the art without departing from the scope of the application. Accordingly, no limitation is intended. The intention is to cover all modifications and alternatives falling within the scope of the claims of the application.

Claims

1. A combustor interstage section structure characterized by, Comprise: an inter-stage section (23) made of ceramic matrix composite material, comprising a first ring structure (231), a second ring structure (232), and a supporting ring surface (233) between the first ring structure (231) and the second ring structure (232); a metal adapter section comprising a connecting piece (21) and a baffle (22) facing each other and defining an annular groove (235) for accommodating the second ring structure (232); an axial spring piece (25) disposed between the baffle (22) and the inter-stage section (23) and located at the outer periphery of the supporting ring surface (233); a radial spring piece (26) located in the annular groove (235) and disposed radially outward of the second ring structure (232); and a fastener (24) for fastening the connecting piece (21) and the baffle (22) and clamping the second ring structure (232) therebetween. The fastener (24) is detachably connected with the connecting piece (21) and the baffle (22).

2. The combustor interstage section structure of claim 1, wherein The fastener (24) penetrates the axial spring piece (25).

3. The combustor interstage section structure according to claim 1, wherein The axial spring piece (25) comprises radial cooling holes.

4. The combustor interstage section structure according to claim 1, wherein The connecting piece (21) is provided with first axial cooling holes (211).

5. The combustor interstage section structure according to claim 1, wherein The first axial cooling holes (211) comprise inner ring cooling holes (2112) facing the end surface of the second ring structure (232) and impact cooling holes (2113) facing the baffle (22).

6. The combustor interstage section structure according to claim 5, wherein The baffle (22) is provided with second axial cooling holes (222) aligned with the impact cooling holes (2113).

7. The combustor interstage section structure according to claim 6, wherein The baffle (22) comprises two semicircular ring structures spliced with each other.

8. The combustor interstage section structure according to claim 1, wherein The axial spring piece (25) disposed between the baffle (22) and the inter-stage section (23) is arranged in an axially pre-tightened state, and the radial spring piece (26) located in the annular groove (235) and radially outward of the second ring structure (232) is arranged in a radially pre-tightened state.

9. The combustor interstage section structure according to claim 1 wherein, Also comprising the combustion chamber inter-stage section structure according to any one of claims 1-9, wherein the connecting piece of the combustion chamber inter-stage section structure is fixedly connected with a pre-combustion stage swirler, and the first ring structure faces the combustion space.

10. A combustor comprising a flame tube, a fuel nozzle, a main stage swirler, a pilot stage swirler, the flame tube defining a combustion space, characterized by, The connecting piece is welded on the pre-combustion stage swirler.

11. The combustion chamber of claim 10, wherein Comprising the combustion chamber according to any one of claims 10-11.

12. An aeroengine characterised in that, ​

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