A combustion chamber test piece
By integrating the diffuser design, using a detachable atomizing device, and employing a bifurcated connecting plate, the problems of combustion chamber sealing and uneven stress distribution are solved, achieving premixing of fuel and air and improving the overall performance of the combustion chamber.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-07
- Publication Date
- 2026-08-04
AI Technical Summary
Existing technologies suffer from sealing problems in combustion chamber design, difficulty in disassembling atomizing devices, unclear impact of flame tube structure on combustion chamber performance, insufficient premixing of fuel and air, and uneven stress due to differences in thermal expansion coefficients between different metal parts.
It adopts an integrated diffuser design, a detachable fuel atomizer, a bifurcated connecting plate, and a "big belly" structure for the flame tube. Combined with a cyclone separator and nozzle, it achieves premixing of fuel and air, and the bifurcated connecting plate alleviates stress problems caused by thermal expansion.
It achieves a simple and easy-to-assemble combustion chamber structure, a detachable atomizing device, facilitates performance research, ensures more complete combustion, has good sealing performance, and alleviates the problem of uneven stress caused by thermal expansion between metal parts.
Smart Images
Figure CN121185634B_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of aero-engine technology, and specifically relates to a combustion chamber test piece. Background Technology
[0002] High-performance engines place higher demands on the combustion chamber: 1) complete combustion within a shorter combustion zone to shorten the chamber length and reduce its weight; 2) better fuel-air mixing in the main combustion zone due to reduced cooling air volume in the high-temperature combustion chamber; and 3) improved ignition and shutdown performance. To fully meet these requirements, atomizing devices have been extensively researched and applied. Currently, comparative tests of different atomizing devices are rarely conducted in China, and the "bulging" flame tube structure is also rarely addressed. Summary of the Invention
[0003] The technical problems to be solved by this invention are: 1) The diffuser is integrated into a single design, which is simple in structure and has no sealing problems; 2) The detachable fuel atomizing device can be used to study the impact of changes in the structure of the flame tube head on the overall performance of the combustion chamber through performance tests of different combustion chambers, which is highly practical; 3) The "big belly" structure of the flame tube can achieve pre-mixing of fuel and air before combustion, which further improves performance; 4) The bifurcated connecting plate design ensures sealing and alleviates the stress caused by the different coefficients of linear expansion between different metal parts.
[0004] This application provides a combustion chamber test specimen, comprising:
[0005] The combustion chamber casing forms an inner cavity with a rectangular cross-section that accommodates the flame tube;
[0006] The diffuser, along the airflow direction, includes in sequence: a convergent section, a transition section, a diffuser section, and a shroud fitting section. The shroud fitting section is fixedly connected to the four walls of the combustion chamber casing, and the rear end face has an air outlet. The edge of the air outlet has an installation edge that connects to the front end of the flame tube.
[0007] The flame tube head is fixedly installed at the front end of the flame tube and has two cyclone mounting holes.
[0008] The ignition device is installed in the combustion chamber housing, with its head extending into the flame tube.
[0009] The cyclone separator and nozzle are mounted on the head of the flame tube.
[0010] The combustion chamber casing (1) is equipped with a viewing window.
[0011] Preferably, the flame tube includes an upper wall and a lower wall, with the two sides of the upper and lower walls fixed to the two sides of the combustion chamber casing. The upper and lower walls of the flame tube form a rectangular opening at the front end, and the edge of the rectangular opening has an mounting edge parallel to the axial direction of the combustion chamber casing.
[0012] Preferably, the flame tube head is rectangular, with mounting edges on all four sides parallel to the axial direction of the combustion chamber casing.
[0013] Preferably, the mounting edge of the diffuser outlet is parallel to the axial direction of the combustion chamber casing, and the mounting edge of the diffuser, the mounting edge of the combustion chamber casing, and the mounting edge of the flame tube are fixedly connected by the same set of bolts.
[0014] Preferably, the joints of multiple bolts are padded with the same forked connector, the forked connector having notches on its edges to alleviate thermal mismatch.
[0015] Preferably, the two nozzles are installed in the central hole of the cyclone separator and are respectively installed on the two side walls of the combustion chamber casing via L-shaped conduits.
[0016] Preferably, the flame tube employs a multi-oblique-hole cooling method, with the multi-oblique holes arranged in an alternating pattern.
[0017] Preferably, the diffuser has a shape that is high at both ends and narrow in the middle.
[0018] Preferably, the maximum height of the flame tube is located between the main combustion zone and the mixing zone.
[0019] The main advantages of this invention are: 1) The rectifier section, parallel transition section, deceleration and diffuser section, and guide fairing section of the test piece are designed as an integrated structure, which is simple, easy to assemble, and highly versatile; 2) The atomizing device can be disassembled, and the influence of changes in the structure of the flame tube head on the overall performance of the combustion chamber can be studied through different head combustion chamber performance tests, which is highly practical; 3) The maximum height of the flame tube is located between the main combustion zone and the mixing zone, forming a "big belly" structure of the flame tube, which can realize the premixing of fuel and air before combustion, resulting in more complete combustion; 4) The connection between the flame tube head and the inner and outer walls adopts a forked connecting plate design, which can not only ensure that the plates are closely attached and sealed to each other when hot, but also alleviate the stress caused by the different linear expansion coefficients between different metal parts. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the test specimen;
[0021] Figure 2 This is a schematic diagram of the fuel main;
[0022] Figure 3 This is a schematic diagram of the diffuser profile;
[0023] Figure 4 This is a schematic diagram of a flame tube;
[0024] Figure 5 This is a schematic diagram of a forked connector.
[0025] Figure 6 This is a schematic diagram of the cooling structure.
[0026] Figure 7 This is a schematic diagram of a hydrocyclone. Detailed Implementation
[0027] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are only some, not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings. Figures 1-7 As shown, this application provides a combustion chamber test piece, comprising:
[0028] Combustion chamber casing 1 forms an inner cavity with a rectangular cross-section to accommodate flame tube 4; forming a double-headed rectangular test specimen structure;
[0029] The diffuser 2 includes, in sequence along the airflow direction: a convergence section, a transition section, a diffuser section, and a shroud fitting section. The shroud fitting section is fixedly connected to the four walls of the combustion chamber casing 1, and has an air outlet on its rear end face. The edge of the air outlet has an installation edge that connects to the front end of the flame tube 4.
[0030] The flame tube head 7 is fixedly installed at the front end of the flame tube 4, and has two cyclone mounting holes; forming a double-headed rectangular test specimen structure.
[0031] Ignition device 6 is installed in combustion chamber housing 1, with its head extending into flame tube 4;
[0032] The cyclone separator and nozzle are installed on the head 7 of the flame tube. The cyclone separator atomizing device adopts a single cyclone and a double cyclone structure respectively, and can be disassembled; the combustion chamber casing (1) is equipped with a window.
[0033] Preferably, the flame tube 4 includes an upper wall and a lower wall, with the two sides of the upper and lower walls fixed to the two sides of the combustion chamber casing 1. The upper and lower walls of the flame tube form a rectangular opening at the front end, and the edge of the rectangular opening has an mounting edge parallel to the axial direction of the combustion chamber casing 1.
[0034] Preferably, the flame tube head 7 is rectangular, with mounting edges on all four sides parallel to the axial direction of the combustion chamber casing 1.
[0035] The maximum height of the flame tube is located between the main combustion zone and the mixing zone, that is, the maximum diameter is located before the half-line of the flame tube, forming a "big belly" structure of the flame tube, which can achieve pre-mixing of fuel and air before combustion, resulting in more complete combustion.
[0036] Preferably, the mounting edge of the diffuser 2 outlet is parallel to the axial direction of the combustion chamber casing 1, and the mounting edges of the diffuser 2, the combustion chamber casing 1, and the flame tube 4 are fixedly connected by the same set of bolts. The rectifier section, parallel transition section, deceleration diffuser section, and fairing mating section of the test piece are designed as an integrated structure.
[0037] Preferably, the connection points of multiple bolts are padded with the same forked connector 3. The forked connector 3 has a notch on its edge to alleviate thermal mismatch. This ensures that the pieces adhere and seal to each other when hot and also alleviates the stress caused by the different coefficients of linear expansion between different metal parts.
[0038] Preferably, the two nozzles are installed in the central hole of the cyclone separator and are respectively installed on the two side walls of the combustion chamber casing 1 through L-shaped conduits. The fuel main is designed with a symmetrical structure, with the fuel inlet pipe located on the lower wall of the casing and the nozzles entering from the side wall of the casing.
[0039] Preferably, the flame tube 4 adopts a multi-oblique hole cooling method, with the multi-oblique holes arranged in an alternating manner. The diameter of the multi-oblique holes is D=0.7mm, the length is L=4.74mm, the length-to-diameter ratio is L / D=6.77, and the inclination angle is 65°.
[0040] Preferably, the diffuser has a shape that is high at both ends and narrow in the middle.
[0041] The main advantages of this invention are: 1. The rectifier section, parallel transition section, deceleration and diffuser section, and guide fairing section of the test piece are designed as an integrated structure, which is simple, easy to assemble, and highly versatile; 2. The atomizing device can be disassembled, and the influence of changes in the structure of the flame tube head on the overall performance of the combustion chamber can be studied through different head combustion chamber performance tests, making it highly practical; 3. The "big belly" structure of the flame tube can achieve pre-mixing of fuel and air before combustion, resulting in more complete combustion; 4. The connection between the flame tube head and the inner and outer walls adopts a forked connecting plate design, which can ensure that the plates are closely fitted and sealed to each other when hot, and can also alleviate the stress caused by the different linear expansion coefficients between different metal parts.
[0042] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A combustion chamber test specimen, characterized in that, include: The flame tube (4) is located inside the combustion chamber casing (1). The maximum height of the flame tube is located between the main combustion zone and the mixing zone, and the maximum diameter is located before the half-line of the flame tube. The combustion chamber casing (1) forms an inner cavity with a rectangular cross-section that accommodates the flame tube (4); The diffuser (2) includes, in sequence along the airflow direction: a convergence section, a transition section, a diffuser section and a guide shroud matching section. The guide shroud matching section is fixedly connected to the four walls of the combustion chamber casing (1). The rear end face has an air outlet, and the edge of the air outlet has an installation edge that is connected to the front end of the flame tube (4). The flame tube head (7) is fixedly installed at the front end of the flame tube (4) and has two swirler mounting holes. Ignition device (6) is installed in combustion chamber housing (1), with its head extending into the flame tube (4); Swirlers and nozzles are mounted on the head (7) of the flame tube; The mounting edge of the diffuser (2) outlet is parallel to the axial direction of the combustion chamber casing (1). The mounting edge of the diffuser (2), the mounting edge of the combustion chamber casing (1), and the mounting edge of the flame tube (4) are fixedly connected by the same set of bolts. The connection of multiple bolts is padded with the same forked connector (3), and the edge of the forked connector (3) is provided with a notch to alleviate thermal mismatch.
2. The combustion chamber test specimen as described in claim 1, characterized in that, The flame tube (4) includes an upper wall and a lower wall. The two sides of the upper and lower walls are fixed to the two sides of the combustion chamber casing (1). The upper and lower walls of the flame tube form a rectangular opening at the front end. The edge of the rectangular opening has an installation edge parallel to the axial direction of the combustion chamber casing (1).
3. The combustion chamber test specimen as described in claim 2, characterized in that, The head of the flame tube (7) is rectangular, with mounting edges on all four sides parallel to the axial direction of the combustion chamber casing (1).
4. The combustion chamber test specimen as described in claim 1, characterized in that, The two nozzles are installed in the central hole of the cyclone separator and are respectively installed on the two side walls of the combustion chamber casing (1) through L-shaped conduits.
5. The combustion chamber test specimen as described in claim 1, characterized in that, The flame tube (4) adopts a multi-oblique hole cooling method, with the multi-oblique holes arranged in an alternating pattern.
6. The combustion chamber test specimen as described in claim 1, characterized in that, The diffuser is high at both ends and narrow in the middle.
7. The combustion chamber test specimen as described in claim 1, characterized in that, The combustion chamber casing (1) is equipped with a viewing window.