Combustion chamber and power system

Abstract

The application relates to the technical field of power equipment, and discloses a combustion chamber and a power system. The combustion chamber comprises a rear end support, a combustion chamber casing, a double-layer wall flame tube and an elastic connecting assembly. The combustion chamber casing comprises an outer casing and an inner casing which are coaxially sleeved; the rear ends of the outer casing and the inner casing are connected with the rear end support; a first cavity is formed between the outer casing and the inner casing; the outer layer flame tube has a rear end open annular second cavity, and the inner layer flame tube is coaxially sleeved in the second cavity; the inner layer flame tube has a rear end open annular third cavity; the first cavity, the second cavity and the third cavity are connected with each other; the rear end of the outer layer flame tube and the rear end of the inner layer flame tube are connected with the rear end support through the elastic connecting assembly, and the elastic connecting assembly is suitable for elastic deformation along the axial direction of the double-layer wall flame tube. The application can solve the problem that the non-metallic composite material and the metal material do not match in thermal expansion under high temperature conditions, thereby causing cracks and breakage of the flame tube.

Description

Technical Field

[0001] This invention relates to the field of power equipment technology, specifically to combustion chambers and power systems. Background Technology

[0002] The future development of aero engines towards higher thrust-to-weight ratios means increasingly higher combustion room temperatures, leading to a greater volume of gases participating in combustion. This results in a sharp decrease in the amount of cooling gas available for the flame tube walls, significantly impacting the flame tube's lifespan. Future high-performance engines will utilize more heat-resistant materials for their flame tubes to ensure extended engine lifespan.

[0003] Currently, conventional combustion chamber flame tubes use high-temperature alloy materials with a maximum temperature resistance of around 900℃, requiring a large amount of cooling gas to reduce the wall temperature. Therefore, it is generally accepted to use newer, more heat-resistant materials, such as ceramic matrix composites. These materials have higher temperature resistance than metal-based materials, with a maximum withstand temperature of up to 1350℃ or even higher, and lower material density, making them one of the most promising heat-resistant materials for aero-engines. Using higher-temperature-resistant and lighter ceramic matrix composites in high-performance engine combustion chambers can further improve the engine's thrust-to-weight ratio.

[0004] However, while using ceramic-based composite flame tubes to solve the high-temperature resistance problem, conventional connection methods inevitably lead to thermal expansion mismatch, causing cracks or even ruptures in the ceramic-based composite flame tubes, thus affecting the normal operation of the engine. Summary of the Invention

[0005] In view of this, the present invention provides a combustion chamber and a power system to solve the problem of cracks and ruptures in the flame tube caused by thermal expansion mismatch.

[0006] In a first aspect, the present invention provides a combustion chamber, comprising a rear support member, a combustion chamber casing, a double-walled flame tube, and an elastic connecting assembly. The combustion chamber casing includes an outer casing and an inner casing axially sleeved together; the rear ends of both the outer and inner casings are connected to the rear support member; an annular first cavity is formed between the outer and inner casings; the double-walled flame tube is disposed in the first cavity, comprising an outer flame tube made of a metal-based material and an inner flame tube made of a non-metal-based composite material, both the outer and inner flame tubes being double-annular structures; the outer flame tube has an annular second cavity with an open rear end, and the inner flame tube is axially sleeved within the second cavity; the inner flame tube has an annular third cavity with an open rear end; the first, second, and third cavities are interconnected; the rear ends of both the outer and inner flame tubes are connected to the rear support member via the elastic connecting assembly, which is adapted to elastically deform along the axial direction of the double-walled flame tube.

[0007] Beneficial effects:

[0008] (1) Due to the double-walled flame tube, the combustion gas is effectively isolated, the high-temperature heat radiation is reduced, the temperature of the combustion chamber outside the combustion chamber is lowered, and the external rubber parts of the engine, such as the fuel main hose and rubber sleeve, are effectively protected, thus improving the service life of the engine.

[0009] (2) Since the inner flame tube is closer to the combustion chamber of the combustion chamber, the inner flame tube is made of non-metallic composite material, which has higher temperature resistance than metal-based materials. During engine operation, the inner flame tube is in direct contact with the gas and can withstand higher gas temperature, effectively reducing the amount of cooling gas on the wall, allowing more air to be used for combustion, increasing the temperature rise of the combustion chamber, and thus improving the thrust-to-weight ratio of the engine.

[0010] (3) Since the outer flame tube is made of metal material and the inner flame tube is made of non-metallic composite material, the two have different coefficients of thermal expansion at high temperature. Therefore, in this invention, the rear end of the outer flame tube and the rear end of the inner flame tube are connected to the rear support through an elastic connection component. The elastic connection component can undergo elastic deformation along the axial direction of the double-walled flame tube. Compared with the traditional rigid connection technology using fixed pins, this invention adopts a flexible connection, which reduces the force on the inner flame tube and solves the problem of thermal expansion mismatch between non-metallic composite material and metal base material under working conditions. This avoids cracks and damage to the inner flame tube made of non-metallic composite material and extends its service life.

[0011] In one optional embodiment, the outer flame tube includes an outer ring and an inner ring, with an annular gap between the outer and inner rings forming a second cavity; the elastic connection assembly includes a first elastic support and a second elastic support, with the rear end of the outer ring connected to the rear end support via the first elastic support, and the inner ring connected to the rear end support via the second elastic support.

[0012] In one optional embodiment, the inner flame tube includes an outer ring and an inner ring, with an annular gap between the outer and inner rings forming a third cavity; the elastic connection assembly further includes a third elastic support and a fourth elastic support, with the rear end of the outer ring connected to the rear end support via the third elastic support, and the inner ring connected to the rear end support via the fourth elastic support.

[0013] In one alternative embodiment, the inner flame tube further includes an inner flame tube head ring, the outer ring of the inner flame tube head ring and the outer ring of the inner flame tube being detachably connected, and the inner ring of the inner flame tube head ring and the inner ring of the inner flame tube being detachably connected.

[0014] In one alternative embodiment, the inner flame tube head ring is provided with a plurality of first mounting holes spaced apart around its axial direction; a swirler is provided in the first mounting hole, and the third cavity communicates with the first cavity through the inner holes of the plurality of swirlers.

[0015] In one optional embodiment, the outer ring of the outer flame tube has a plurality of outer ring air inlets on its outer wall, and the inner ring of the outer flame tube has a plurality of outer ring air inlets on its inner wall. The outer ring air inlets, the outer ring air inlets, the first cavity, and the second cavity are interconnected.

[0016] In one optional embodiment, a flow guide is further included, comprising a mounting cylinder and a flow guide plate disposed on the side wall of the mounting cylinder; the mounting cylinder is disposed in a first mounting hole, and the cyclone separator is detachably connected to the mounting cylinder; the flow guide plate is disposed in a third cavity, and the flow guide plate includes a head flow guide section extending radially along the mounting cylinder and an outer ring flow guide section and an inner ring flow guide section bent axially from the head flow guide section; the outer side of the head flow guide section abuts against the outer ring of the inner flame tube head ring through a fifth elastic support member, and the inner side of the head flow guide section abuts against the inner ring of the inner flame tube head ring through a sixth elastic support member.

[0017] In one optional embodiment, the outer flame tube further includes an outer flame tube head ring, which connects the outer ring and the inner ring of the outer flame tube. The outer flame tube head ring is provided with a plurality of second mounting holes spaced apart axially around the outer flame tube. The second mounting holes are correspondingly provided and connected to the first mounting holes for mounting the flow guide. The outer ring of the outer flame tube head ring abuts against the outer ring of the inner flame tube head ring through a seventh elastic support member, and the inner ring of the outer flame tube head ring abuts against the inner ring of the inner flame tube head ring through an eighth elastic support member.

[0018] In one optional embodiment, the outer ring sidewall of the outer flame tube head ring is provided with a plurality of head ring outer ring air inlets spaced apart circumferentially, and the inner ring sidewall of the outer flame tube head ring is provided with a plurality of head ring inner ring air inlets spaced apart circumferentially.

[0019] Secondly, the present invention also provides a power system including the double-walled flame tube of any of the above embodiments.

[0020] Beneficial effects: Since the power system includes a combustion chamber, it has the same effects as the combustion chamber, which will not be elaborated here. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art 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.

[0022] Figure 1 This is a side view of a combustion chamber according to an embodiment of the present invention;

[0023] Figure 2 For along Figure 1 Sectional view at point AA;

[0024] Figure 3 This is a schematic diagram of the outer wall flame tube structure;

[0025] Figure 4 for Figure 3 The side view of the outer wall flame tube shown;

[0026] Figure 5 For along Figure 4 Sectional view at point BB;

[0027] Figure 6 This is a schematic diagram of the structure of the outer ring of the inner flame tube;

[0028] Figure 7 for Figure 6 A partial sectional view from a side perspective;

[0029] Figure 8 This is a schematic diagram of the inner ring structure of the inner flame tube;

[0030] Figure 9 for Figure 8 A partial sectional view from a side perspective;

[0031] Figure 10 This is a schematic diagram of the structure of the head ring of the inner flame tube;

[0032] Figure 11 for Figure 10 The side view of the inner flame tube head ring shown;

[0033] Figure 12 For along Figure 11 Sectional view at point DD;

[0034] Figure 13 This is a schematic diagram of the flow guide component;

[0035] Figure 14 for Figure 13 Side view;

[0036] Figure 15 For along Figure 14 Sectional view at CC;

[0037] Figure 16 This is a structural schematic diagram of the third support component;

[0038] Figure 17 for Figure 16 A magnified view of a section from a side perspective;

[0039] Figure 18 This is a structural schematic diagram of the fourth support component;

[0040] Figure 19 for Figure 18 A magnified view of a portion from a side perspective.

[0041] Explanation of reference numerals in the attached figures:

[0042] 1. Diffuser outer ring; 2. Outer casing; 3. Cap outer ring; 4. Outer ring of outer flame tube: 401. Outer ring air inlet; 402. First elastic support; 403. Outer ring connecting hole; 5. Outer flame tube head ring: 501. Seventh elastic support; 502. Eighth elastic support; 503. Second mounting hole; 504. Head ring outer ring air inlet; 505. Head ring inner ring air inlet; 6. Cap inner ring; 7. Outer flame tube inner ring; 701. 702. Outer inner ring air inlet; 703. Second elastic support; 704. Outer inner ring connecting hole; 8. Flow guide; 805. Fifth elastic support; 806. Sixth elastic support; 807. Mounting cylinder; 808. Outer ring flow guide section; 809. Inner ring flow guide section; 8000. Baffle; 900. Inner flame tube head ring: 901. First mounting hole; 902. Head ring outer ring cooling hole; 903. Head ring inner ring cooling hole; 904. Inner outer ring overlapping section; 905. 10. Inner ring overlap section; 10. Inner flame tube outer ring; 1001. Outer ring stop overlap section; 1002. Inner outer ring cooling hole; 1003. Outer ring main combustion hole; 1005. Outer ring mixing hole; 11. Third elastic support; 1101. Front support section; 1102. Second elastic bending section; 1103. Rear support section; 12. Swirl generator; 13. Inner flame tube inner ring; 1301. Inner ring stop overlap section; 1302. Inner ring cooling hole; 130 3. Inner ring main combustion port; 1305. Inner ring mixing port; 14. Fourth elastic support; 1401. Positioning front end face; 1402. Elastic bending structure; 1403. Overlapping rear section; 1404. Impact cooling hole; 1406. Positioning rear end face; 15. Diffuser inner ring; 16. Inner casing; 17. Flared self-locking nut; 18. Screw; 19. Outer ring sealing gasket; 20. Rear end outer ring overlapping section; 21. Inner ring sealing gasket; 22. Rear end inner ring overlapping section. Detailed Implementation

[0043] 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.

[0044] Currently, existing flame tubes use a direct overlap or clearance fit structure between non-metallic composite flame tubes and metallic structures (including guide vanes, fixing pins, or electric nozzles). The outlet positions of the inner and outer rings of the flame tube and structures such as turbine casings and turbine guide vanes adopt a conventional bird beak structure.

[0045] This invention provides a combustion chamber that mainly solves the following problems: 1) the technical difficulties of high-performance engine combustion chamber temperature rise, low cooling gas volume, and insufficient high-temperature resistance of the flame tube; 2) the problem of flame tube cracking and rupture caused by thermal expansion mismatch between ceramic matrix composite flame tube and metal matrix connection structure during engine combustion chamber operation.

[0046] The following is combined Figures 1 to 19 The following describes embodiments of the present invention.

[0047] According to an embodiment of the present invention, a combustion chamber is provided, comprising a rear support member, a combustion chamber casing, a double-walled flame tube, and an elastic connecting assembly. The combustion chamber casing includes an outer casing 2 and an inner casing 16 axially sleeved together; the rear ends of both the outer casing 2 and the inner casing 16 are connected to the rear support member; an annular first cavity is formed between the outer casing 2 and the inner casing 16; the double-walled flame tube is disposed in the first cavity, the double-walled flame tube comprising an outer flame tube made of a metal-based material and an inner flame tube made of a non-metal-based composite material, both the outer and inner flame tubes being double-annular structures, the outer flame tube having an annular second cavity with an open rear end, the inner flame tube being axially sleeved in the second cavity; the inner flame tube having an annular third cavity with an open rear end; the first cavity, the second cavity, and the third cavity are interconnected; the rear ends of both the outer and inner flame tubes are connected to the rear support member via the elastic connecting assembly, the elastic connecting assembly being adapted to elastically deform along the axial direction of the double-walled flame tube.

[0048] The combustion chamber provided in this embodiment of the invention has the following beneficial effects:

[0049] (1) Due to the double-walled flame tube, the combustion gases are effectively isolated, reducing high-temperature heat radiation and lowering the temperature of the outer casing 2 of the combustion chamber. This effectively protects the external rubber parts of the engine, such as the fuel main hose and rubber sleeve, thus improving the engine's service life. This invention is verified through numerical simulation calculations and related ceramic matrix composite material sample tests. The calculation results show that the engine combustion chamber temperature rise exceeds 1200℃, and the inner ceramic matrix composite flame tube can withstand high temperatures up to 1500K.

[0050] (2) Since the inner flame tube is closer to the combustion chamber of the combustion chamber, the inner flame tube is made of non-metallic composite material, which has higher temperature resistance than metal-based materials. During engine operation, the inner flame tube is in direct contact with the gas and can withstand higher gas temperature, effectively reducing the amount of cooling gas on the wall, allowing more air to be used for combustion, increasing the temperature rise of the combustion chamber, and thus improving the thrust-to-weight ratio of the engine.

[0051] (3) Since the outer flame tube is made of metal material and the inner flame tube is made of non-metallic composite material, the two have different coefficients of thermal expansion at high temperature. Therefore, in this invention, the rear end of the outer flame tube and the rear end of the inner flame tube are connected to the rear support through an elastic connection component. The elastic connection component can undergo elastic deformation along the axial direction of the double-walled flame tube. Compared with the traditional rigid connection technology using fixed pins, this invention adopts a flexible connection, which reduces the force on the inner flame tube and solves the problem of thermal expansion mismatch between non-metallic composite material and metal base material under working conditions. This avoids cracks and damage to the inner flame tube made of non-metallic composite material and extends its service life.

[0052] In one embodiment, the inner flame tube is a high-temperature resistant ceramic matrix composite flame tube. The non-metallic matrix composite material uses ceramic matrix composites, including but not limited to SiCf / SiC ceramic matrix composites.

[0053] In one embodiment, the outer flame tube is a thin-walled metal-based high-temperature alloy flame tube, and the metal base material is a high-temperature resistant alloy material, such as GH3536, GH5188, etc.

[0054] In one embodiment, the outer flame tube includes an outer ring 4 and an inner ring 7, and the annular gap between the outer ring 4 and the inner ring 7 forms a second cavity; the elastic connection assembly includes a first elastic support 402 and a second elastic support 702, the rear end of the outer ring 4 is connected to the rear end support through the first elastic support 402, and the inner ring 7 is connected to the rear end support through the second elastic support 702.

[0055] Specifically, in one embodiment, the first elastic support 402 includes a front connecting section, a first elastic bending section and a rear connecting section that are connected to each other. The front connecting section is connected to the outer ring 4 of the outer flame tube, and the rear connecting section is connected to the rear support.

[0056] The first elastic bending section provides elastic deformation capability through its bending structure.

[0057] The structure of the second elastic support 702 is similar to or the same as that of the first elastic support 402. When the structure of the second elastic support 702 is the same as that of the first elastic support 402, the front connecting section of the second elastic support 702 is connected to the inner ring 7 of the outer flame tube, and the rear connecting section is connected to the rear support.

[0058] Specifically, the first elastic support 402 and the outer ring 4 of the outer flame tube can be separate or integrated. Similarly, the second elastic support 702 and the inner ring 7 of the outer flame tube can be separate or integrated.

[0059] Specifically, the rear support includes a rear outer ring overlap section 20 and a rear inner ring overlap section 22. The rear outer ring overlap section 20 is used to establish a connection with the outer ring 10 of the inner flame tube, and the rear inner ring overlap section 22 is used to establish a connection with the inner ring 13 of the inner flame tube.

[0060] Furthermore, the rear connecting section of the first elastic support 402 is provided with an outer ring connecting hole 403, which can be fastened to the outer ring mounting edge of the rear support by bolts.

[0061] Furthermore, the rear connecting section of the second elastic support 702 is provided with an outer inner ring connecting hole 703, which can be fastened to the inner ring mounting edge of the rear support by bolts.

[0062] In one embodiment, the inner flame tube includes an outer ring 10 and an inner ring 13, and the annular gap between the outer ring 10 and the inner ring 13 forms a third cavity; the elastic connection assembly further includes a third elastic support 11 and a fourth elastic support 14, the rear end of the outer ring 10 is connected to the rear end support through the third elastic support 11, and the inner ring 13 is connected to the rear end support through the fourth elastic support 14.

[0063] Specifically, in one embodiment, the third elastic support 11 includes a front support section 1101, a second elastic bending section 1102 and a rear support section 1103. The front support section 1101 abuts against the outer ring 10 of the inner flame tube, and the rear support section 1103 abuts against the rear support member.

[0064] The front support section 1101 is pressed against the outer ring 10 of the inner flame tube to support and limit the outer ring 10. The second elastic bending section 1102 has an elastic energy storage function in the working state, realizing an elastic and flexible connection. The rear support section 1103 overlaps with the rear outer ring overlapping section 20 and bears axial force to form axial positioning.

[0065] In this embodiment, the fourth elastic support 14 includes an outer ring layer and an inner ring layer. The front end connection between the outer ring layer and the inner ring layer forms a positioning front end surface 1401. The outer ring layer also includes an elastic bending structure 1402 and an overlapping rear section 1403. The rear end of the inner ring layer is bent to form a positioning rear end surface 1406. The inner ring layer is provided with a plurality of impact cooling holes 1404.

[0066] The positioning front face 1401 is pressed against the inner ring 13 of the inner flame tube to support and limit the inner ring 13 of the inner flame tube. The elastic bending structure 1402 has an elastic support function. The overlapping rear section 1403 and the positioning rear end face 1406 overlap with the overlapping section 22 of the rear inner ring to form axial positioning. The impact cooling hole 1404 is used for cooling the elastic bending structure 1402 and the overlapping rear section 1403, effectively extending the service life of the fourth elastic support 14.

[0067] The third elastic support 11 is compressed so that it abuts against the outer ring 10 of the inner flame tube and the rear support, facilitating disassembly and assembly, effectively reducing the maintenance cost of the flame tube, and has high engineering application value. Similarly, the fourth elastic support 14 is compressed so that it abuts against the inner ring 13 of the inner flame tube and the rear support, achieving the same technical effect as the third elastic support 11.

[0068] Specifically, the third elastic support 11 and the fourth elastic support 14 are both annular structures adapted to the inner flame tube, and both are made of metal-based materials.

[0069] In one embodiment, the inner flame tube further includes an inner flame tube head ring 9, the outer ring of the inner flame tube head ring 9 and the outer ring 10 of the inner flame tube are detachably connected, and the inner ring of the inner flame tube head ring 9 and the inner ring 13 of the inner flame tube are detachably connected.

[0070] Since the inner flame tube head ring 9, the inner flame tube outer ring 10, and the inner flame tube inner ring 13 are detachably connected, they are easy to disassemble and assemble, effectively reducing the maintenance cost of the flame tube and having high engineering application value.

[0071] Specifically, the outer ring of the inner flame tube head ring 9 and the outer ring 10 of the inner flame tube are detachably connected through a stop-and-lap structure, and the inner ring of the outer flame tube head ring 5 and the inner ring 13 of the inner flame tube are detachably connected through a stop-and-lap structure.

[0072] Specifically, in one embodiment, the outer ring of the inner flame tube head ring 9 is provided with an outer ring overlapping stop, and the inner ring of the inner flame tube head ring 9 is provided with an inner ring overlapping stop. Further, in this embodiment, multiple outer ring overlapping stops and inner ring overlapping stops are provided at intervals along the circumference of the inner flame tube head ring 9.

[0073] Correspondingly, the outer ring 10 of the inner flame tube is provided with an outer ring lap joint section 1001 that mates with the outer ring lap joint stop of the inner flame tube head ring 9. When the outer ring of the inner flame tube 10 is assembled with the outer ring of the inner flame tube head ring 9, the inner outer ring lap joint section 904 of the inner flame tube 10 is overlapped with the outer ring lap joint stop of the inner flame tube head ring 9.

[0074] Similarly, the inner ring 13 of the inner flame tube is provided with an inner ring overlap section 905 that mates with the inner ring overlap stop of the inner flame tube head ring 9. The assembly method is the same.

[0075] In one embodiment, the inner flame tube head ring 9 is provided with a plurality of first mounting holes 901 spaced around its axial direction; a swirler 12 is provided in the first mounting hole 901, and the third cavity is connected to the first cavity through the inner holes of the plurality of swirlers 12.

[0076] Since several first mounting holes 901 are spaced apart along the circumference of the inner flame tube, several swirlers 12 are also correspondingly provided. In one embodiment, a portion of the airflow passes through the swirlers 12 and enters the third cavity to participate in organizing combustion.

[0077] In one embodiment, the outer ring 4 of the outer flame tube has a plurality of outer ring air inlets 401 on its cylinder wall, and the inner ring 7 of the outer flame tube has a plurality of inner ring air inlets 701 on its cylinder wall. The outer ring air inlets 401, the inner ring air inlets 701, the first cavity and the second cavity are interconnected.

[0078] The airflow entering the first cavity of the combustion chamber casing is divided into three streams: the outer ring airflow, the head airflow, and the inner ring airflow. The outer ring airflow enters the second cavity through the outer outer ring inlet 401 located on the outer ring 4 of the outer flame tube, and the inner ring airflow enters the second cavity through the outer inner ring inlet 701 located on the inner ring 7 of the outer flame tube.

[0079] In one embodiment, a flow guide 8 is also included, which includes a mounting cylinder 803 and a flow guide plate disposed on the side wall of the mounting cylinder 803; the mounting cylinder 803 is disposed in a first mounting hole 901, and the cyclone separator 12 is detachably connected to the mounting cylinder 803; the flow guide plate is disposed in a third cavity, and the flow guide plate includes a head flow guide section extending radially along the mounting cylinder 803 and an outer ring flow guide section 804 and an inner ring flow guide section 805 bent axially from the head flow guide section; the outer side of the head flow guide section abuts against the outer ring of the inner flame tube head ring 9 through a fifth elastic support member 801, and the inner side of the head flow guide section abuts against the inner ring of the inner flame tube head ring 9 through a sixth elastic support member 802.

[0080] Since the cyclone separator 12 is detachably connected to the mounting cylinder 803 of the guide member 8, it is easy to disassemble and assemble, which helps to reduce maintenance costs.

[0081] Specifically, in one embodiment, the inner wall of the mounting cylinder 803 of the flow guide 8 is provided with an internal thread, the outer wall of the cyclone separator 12 is provided with an external thread, and the cyclone separator 12 and the mounting cylinder 803 of the flow guide 8 are threadedly connected.

[0082] The head guide section extends radially along the mounting cylinder 803, while the outer ring guide section 804 and the inner ring guide section 805 extend axially along the mounting cylinder 803. The head guide section and the outer ring guide section 804 and inner ring guide section 805 have a smooth transition. The outer ring guide section 804 and the inner ring guide section 805 can guide the airflow.

[0083] Since the cyclone separators 12 are arranged at intervals along the circumference of the annular first cavity, the mounting cylinders 803 of the guide plates are also arranged at intervals along the circumference of the first cavity. The guide member 8 can be a single annular structure or multiple separate structures. To accommodate the annular structure of the first cavity, the head guide section of the guide member 8 is configured as a fan-shaped structure surrounding the double-walled flame tube along the axial direction.

[0084] Furthermore, in one embodiment, the flow guide 8 is made of a high-temperature resistant alloy material, including but not limited to GH3536 or GH5188. It is also a replaceable component for actual use.

[0085] Specifically, in one embodiment, both the fifth elastic support 801 and the sixth elastic support 802 are support springs. The fifth elastic support 801 is supported and fixed to the inner ring of the inner flame tube head ring 9.

[0086] Furthermore, in one embodiment, a baffle 806 is provided on the side of the head guide section facing away from the second guide section. The baffle 806 extends from the outer side of the head guide section to the inner side of the head guide section. The "outer side of the head guide section" refers to the side of the head guide section near the outer ring 10 of the inner flame tube. Similarly, the "inner side of the head guide section" refers to the side of the head guide section near the inner ring 13 of the inner flame tube.

[0087] Furthermore, in one embodiment, a baffle 806 is provided on each side of the mounting cylinder 803. The baffle 806 is used to isolate the airflow distribution between the various heads and reduce the airflow influence between the various heads.

[0088] In one embodiment, the outer flame tube further includes an outer flame tube head ring 5, which connects the outer flame tube outer ring 4 and the outer flame tube inner ring 7. The outer flame tube head ring 5 is provided with a plurality of second mounting holes 503 at axial intervals around the outer flame tube. The second mounting holes 503 are correspondingly provided and connected to the first mounting holes 901 for mounting the guide member 8. The outer ring of the outer flame tube head ring 5 abuts against the outer ring of the inner flame tube head ring 9 through the seventh elastic support member 501, and the inner ring of the outer flame tube head ring 5 abuts against the inner ring of the inner flame tube head ring 9 through the eighth elastic support member 502.

[0089] Specifically, in one embodiment, the guide member 8 passes through the first mounting hole 901 of the inner flame tube head ring 9 and the second mounting hole 503 of the outer flame tube head ring 5.

[0090] The flow guide 8 is fixedly connected to the second mounting hole 503 by spot welding, and is clearance-fitted to the first mounting hole 901. The size of the clearance is designed to match the thermal expansion, so as to avoid direct contact with the head ring 9 of the inner flame tube, prevent excessive local stress, and avoid cracks and ruptures in the inner flame tube.

[0091] The outer ring of the outer flame tube head ring 5 and the outer ring of the inner flame tube head ring 9 are abutted by the seventh elastic support member 501, and the inner ring of the outer flame tube head ring 5 and the inner ring of the inner flame tube head ring 9 are abutted by the eighth elastic support member 502, so that the outer flame tube head ring 5 and the inner flame tube head ring 9 do not directly contact each other and have elastic support performance, effectively reducing the generation of local stress concentration.

[0092] In one embodiment, the inner flame tube head ring 9 further includes an outer ring cooling hole 902, an inner ring cooling hole 903, an outer ring overlap section 904, and an inner ring overlap section 905. The outer ring cooling hole 902 and the inner ring cooling hole 903 form a diffused cooling effect between the inner and outer rings of the flame tube, reducing the wall temperature. The outer ring overlap stop and the inner ring overlap stop overlap with the outer ring overlap section 1001 and the inner ring overlap section 1301 of the inner flame tube outer ring 10, respectively. Both the outer ring overlap stop and the inner ring overlap stop adopt an intermittent distribution design, effectively improving strength and sealing performance.

[0093] In one embodiment, the outer ring sidewall of the outer flame tube head ring 5 is provided with a plurality of head ring outer ring air inlets 504 spaced apart around the circumference, and the inner ring sidewall of the outer flame tube head ring 5 is provided with a plurality of head ring inner ring air inlets 505 spaced apart around the circumference.

[0094] Furthermore, the diameter of the air inlet 504 on the outer ring of the head ring and the air inlet 505 on the inner ring of the head ring is 0.5 to 2.5 mm.

[0095] Furthermore, the head sidewall of the outer flame tube head ring 5 is provided with an outer ring impact hole 506 near the outer ring and an inner ring impact hole 507 near the inner ring. The outer ring impact hole 506 and the inner ring impact hole 507 are used to cool the flow guide 8.

[0096] The outer ring guide section 804 and the inner ring guide section 805 of the guide component 8 guide the outer ring impact hole 506 and the inner ring impact hole 507 on the head ring 5 of the outer flame tube to both sides of the outer and inner rings of the flame tube, so as not to affect the mainstream combustion.

[0097] Furthermore, the wall thickness of the outer ring 4 and the inner ring 7 of the outer flame tube is 0.3–1.5 mm, and the diameter of the air inlet 401 of the outer ring and the air inlet 701 of the inner ring is 0.5–2.5 mm, with the number determined according to the pressure loss requirements of the flame tube. The mounting edge of the rear support component is provided with second connecting holes, the number of which is 32–96.

[0098] Furthermore, the wall thickness of the outer flame tube head ring 5 is 0.3 to 1.5 mm, the number of the seventh elastic support 501 and the eighth elastic support 502 is 80 to 160, the diameter of the second mounting hole 503 is 25 to 45 mm, and the number corresponds to the number of flame tube head rings, which is 8 to 24.

[0099] Furthermore, the number of the fifth elastic support member 801 and the sixth elastic support member 802 is 5 to 10. The total number of the flame tube guide members 8 is designed to match the number of the inner flame tube head ring 9, ranging from 8 to 24.

[0100] Furthermore, the number of first mounting holes 901 in the inner flame tube head ring 9 corresponds to the number of inner flame tube head rings 9, ranging from 8 to 24. The cooling holes 902 in the outer ring of the head ring and the cooling holes 903 in the inner ring of the head ring are divergent cooling holes. Considering that the ceramic matrix composite material has good cooling performance, the diameter of the divergent holes is relatively large and the number is small, with a diameter of 0.7 to 1.2 mm and a number of 60 to 100 per row.

[0101] The temperature of the outer ring 10 of the inner flame tube is too high, so the number of cooling holes 1002 in the inner outer ring is too large, ranging from 80 to 150 per row. The specific number of rows is determined based on the aerodynamic design and numerical simulation results of the wall temperature. The main combustion holes 1003 and mixing holes 1005 in the outer ring are the main air intake for combustion, with a hole diameter ranging from 3.0 to 6.5 mm and a number ranging from 18 to 36.

[0102] The temperature of the inner ring 13 of the inner flame tube is relatively high, so the number of cooling holes 1302 in the inner ring is relatively large, ranging from 80 to 150 per row. The specific number of rows is determined based on the aerodynamic design and numerical simulation results of the wall temperature. The inner ring main combustion holes 1303 and inner ring mixing holes 1305 are designed to match the outer ring main combustion holes 1003 and mixing holes, with hole diameters ranging from 3.0 to 6.5 mm and a number ranging from 18 to 36.

[0103] The second elastic bending section 1102 of the third elastic support 11 and the elastic bending structure 1402 of the fourth elastic support 14 adopt S, W, or other shapes, with 5 to 10 bends, effectively improving the elastic support capacity. Under working conditions, they offset deformation in high-temperature environments and support the outer ring 10 of the inner flame tube. Among them, the contact area of ​​the elastic bending structure 1402 of the fourth elastic support 14 is increased, and with the multiple rows of impact cooling holes 1404 designed on the inner side, the wall temperature of the fourth elastic support 14 can be effectively reduced, thus improving its service life.

[0104] Furthermore, in one embodiment, the double-walled flame tube also includes a cap. The cap is located at the head of the outer flame tube. The cap includes an outer ring 3 and an inner ring 6, which are fixed to the outer metal-based flame tube by welding. It has a flow-rectifying function, dividing the inlet airflow into three streams: the outer ring airflow, the head airflow, and the inner ring airflow.

[0105] The outer ring airflow enters the flame tube through the outer ring air inlet 401 of the outer ring 4 of the outer flame tube, and participates in cooling and combustion organization; the head airflow enters the third cavity of the flame tube through the vortex generator 12 and participates in combustion organization; the inner ring airflow enters the flame tube through the outer ring air inlet 701 of the inner ring 7 of the outer flame tube, and participates in cooling and combustion organization.

[0106] Furthermore, the outer ring 10 of the inner flame tube is provided with several inner outer ring cooling holes 1002, outer ring main combustion holes 1003, and outer ring mixing holes 1005. The outer ring airflow after passing through the outer ring 3 of the cap flows through the inner outer ring cooling holes 1002 to cool the inner outer ring 10 of the inner flame tube, and the outer ring airflow flows through the outer ring main combustion holes 1003 and outer ring mixing holes 1005 to enter the interior of the flame tube to participate in organizing combustion.

[0107] Furthermore, the inner ring 13 of the inner flame tube is provided with several inner ring cooling holes 1302, inner ring main combustion holes 1303, and inner ring mixing holes 1305. The inner ring airflow passing through the inner ring 6 of the cap flows through the inner ring cooling holes 1302 to cool the inner ring 13 of the inner flame tube, and the inner ring airflow flows through the ring main combustion holes and inner ring mixing holes 1305 to enter the interior of the flame tube to participate in organizing combustion.

[0108] Furthermore, the combustion chamber also includes a diffuser located at the front end of the combustion chamber casing. The diffuser is adapted to the burner and is also annular in structure. The diffuser includes an inner diffuser ring 15 and an outer diffuser ring 1. The inner diffuser ring 15 is connected to the inner casing 16 of the combustion chamber, and the outer diffuser ring 1 is connected to the outer casing 2 of the combustion chamber. A fourth annular cavity is also formed between the inner diffuser ring 15 and the outer diffuser ring 1, serving as the air inlet. The fourth cavity communicates with the first cavity. The inner diffuser ring 15 and the outer diffuser ring 1 are used to reduce the compressor outlet velocity, facilitating combustion within the combustion chamber.

[0109] The rear mounting edge of the outer casing 2 of the combustion chamber is sealed to the outer ring 4 of the outer flame tube. Specifically, the rear mounting edge of the outer casing 2 of the combustion chamber is provided with a third connecting hole, which is connected and fixed to the outer ring 4 of the outer flame tube, the outer ring sealing gasket 19, and the rear outer ring overlapping section 20 by screws 18 and flared self-locking nuts 17 to form a closed area, constituting the outer ring cavity of the flame tube.

[0110] The rear mounting edge of the inner casing 16 of the combustion chamber is sealed to the outer ring 10 of the inner flame tube. Specifically, the rear mounting edge of the inner casing 16 of the combustion chamber has a fourth connecting hole, which is connected and fixed to the outer flame tube inner ring 7, the inner ring sealing gasket 21, and the rear inner ring overlapping section 22 by screws 18 and flared self-locking nuts 17, forming a closed area that constitutes the inner ring cavity of the flame tube. In this way, the axial force on the flame tube is transmitted through the outer flame tube outer ring 4 and the outer flame tube inner ring 7 to the outer casing 2 of the combustion chamber, the inner casing 16 of the combustion chamber, the rear outer ring overlapping section 20, and the rear inner ring overlapping section 22, avoiding the inner flame tube from being subjected to large axial forces, thereby preventing cracks and ruptures caused by extrusion deformation.

[0111] According to an embodiment of the present invention, in another aspect, a power system is also provided, including the double-walled flame tube of any of the above embodiments.

[0112] Specifically, the power system includes aircraft engines or ground-based gas turbines.

[0113] The power system includes a double-walled flame tube according to any of the above embodiments. The rear end of the double-walled flame tube is connected to a rear support member via an elastic connecting component. The axial force of the engine is transmitted through this structure, reducing the force on the inner flame tube and preventing the inner flame tube from contacting the fixing pin. This solves the problem of thermal expansion mismatch between non-metallic composite materials and metallic materials during operation; it also reduces the occurrence of cracks and damage to the outer ring 10 of the inner flame tube, extending its service life. The inner flame tube, made of non-metallic composite material, has high-temperature resistance, with a maximum temperature resistance of up to 1350℃. During engine operation, it is in direct contact with the combustion gas and can withstand higher combustion gas temperatures, effectively reducing the amount of cooling gas required for the wall surface, allowing more air to be used for combustion, increasing the temperature rise of the combustion chamber, and thus improving the engine's thrust-to-weight ratio. Furthermore, the outer ring, inner ring, and head ring of the inner flame tube adopt a stop-joint structure, a split design, and good disassembly, replaceability, and assembly performance. In case of flame tube erosion, cracking, or other failures, it can be repaired individually, effectively improving the maintainability of the flame tube, reducing maintenance costs, and possessing high engineering application value.

[0114] Furthermore, since the power system includes a combustion chamber and has all the same effects as the combustion chamber, it will not be elaborated upon here.

[0115] 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 the appended claims.

Claims

1. A combustion chamber, characterized in that, include: Back-end support components; The combustion chamber casing includes an outer casing (2) and an inner casing (16) sleeved along the axial direction; the rear ends of the outer casing (2) and the inner casing (16) are both connected to the rear end support; the outer casing (2) and the inner casing (16) form an annular first cavity. A double-walled flame tube; the double-walled flame tube is disposed in the first cavity, the double-walled flame tube includes an outer flame tube made of a metal-based material and an inner flame tube made of a non-metal-based composite material, both the outer flame tube and the inner flame tube are double-ring structures, the outer flame tube has an annular second cavity with an open rear end, the inner flame tube is axially sleeved in the second cavity; the inner flame tube has an annular third cavity with an open rear end; the first cavity, the second cavity and the third cavity are interconnected; An elastic connection assembly is provided, wherein the rear ends of the outer flame tube and the inner flame tube are both connected to the rear end support member via the elastic connection assembly, and the elastic connection assembly is adapted to undergo elastic deformation along the axial direction of the double-walled flame tube. The outer flame tube includes an outer ring (4) and an inner ring (7), and the annular gap between the outer ring (4) and the inner ring (7) forms the second cavity; The elastic connection assembly includes a first elastic support (402) and a second elastic support (702). The rear end of the outer ring (4) of the outer flame tube is connected to the rear end support through the first elastic support (402), and the inner ring (7) of the outer flame tube is connected to the rear end support through the second elastic support (702). The inner flame tube includes an outer ring (10) and an inner ring (13), and the annular gap between the outer ring (10) and the inner ring (13) forms the third cavity. The elastic connection assembly further includes a third elastic support (11) and a fourth elastic support (14). The rear end of the outer ring (10) of the inner flame tube is connected to the rear end support through the third elastic support (11), and the inner ring (13) of the inner flame tube is connected to the rear end support through the fourth elastic support (14).

2. The combustion chamber according to claim 1, characterized in that, The inner flame tube also includes an inner flame tube head ring (9), the outer ring of the inner flame tube head ring (9) and the outer ring (10) of the inner flame tube are detachably connected, and the inner ring of the inner flame tube head ring (9) and the inner ring (13) of the inner flame tube are detachably connected.

3. The combustion chamber according to claim 2, characterized in that, The inner flame tube head ring (9) is provided with a plurality of first mounting holes (901) spaced around its axial direction; a vortex (12) is provided in the first mounting hole (901), and the third cavity is connected to the first cavity through the inner holes of the plurality of the vortex (12).

4. The combustion chamber according to any one of claims 1 to 3, characterized in that, The outer ring (4) of the outer flame tube has a plurality of outer ring air inlets (401) on its cylinder wall, and the inner ring (7) of the outer flame tube has a plurality of inner ring air inlets (701) on its cylinder wall. The outer ring air inlets (401), the inner ring air inlets (701), the first cavity and the second cavity are interconnected.

5. The combustion chamber according to claim 3, characterized in that, It also includes a flow guide (8), which includes a mounting cylinder (803) and a flow guide plate disposed on the side wall of the mounting cylinder (803); The mounting cylinder (803) is disposed in the first mounting hole (901), and the cyclone separator (12) is detachably connected to the mounting cylinder (803); The guide plate is disposed in the third cavity. The guide plate includes a head guide section extending radially along the mounting cylinder (803) and an outer ring guide section (804) and an inner ring guide section (805) bent axially from the head guide section. The outer side of the head guide section abuts against the outer ring of the inner flame tube head ring (9) through a fifth elastic support member (801), and the inner side of the head guide section abuts against the inner ring of the inner flame tube head ring (9) through a sixth elastic support member (802).

6. The combustion chamber according to claim 5, characterized in that, The outer flame tube also includes an outer flame tube head ring (5), which connects the outer flame tube outer ring (4) and the outer flame tube inner ring (7). The outer flame tube head ring (5) is provided with a plurality of second mounting holes (503) spaced apart around the axial direction of the outer flame tube. The second mounting holes (503) and the first mounting holes (901) are correspondingly arranged and connected for mounting the guide (8). The outer ring of the outer flame tube head ring (5) abuts against the outer ring of the inner flame tube head ring (9) through the seventh elastic support (501). The inner ring of the outer flame tube head ring (5) abuts against the inner ring of the inner flame tube head ring (9) through the eighth elastic support (502).

7. The combustion chamber according to claim 6, characterized in that, The outer ring sidewall of the outer flame tube head ring (5) is provided with a plurality of head ring outer ring air inlets (504) spaced around the circumference, and the inner ring sidewall of the outer flame tube head ring (5) is provided with a plurality of head ring inner ring air inlets (701) spaced around the circumference.

8. A power system, characterized in that, It includes the combustion chamber according to any one of claims 1 to 7.

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