Combustion chamber structure with movable cowl

Abstract

This invention provides a combustor structure with a movable cap, relating to the field of aero-engine combustor technology. It includes: a combustor housing; a flame tube disposed within the combustor housing; a pre-diffuser disposed upstream of the flame tube's intake; a cap axially movably disposed at the flame tube's intake end and opposite to the pre-diffuser; a connecting rod, the first end of which is connected to the cap; and a pull rod, the first end of which is connected to the second end of the connecting rod, the second end of which extends from a mounting base on the combustor housing to the outside. By axially moving the pull rod, the connecting rod drives the cap to move axially relative to the flame tube, thereby changing the relative position between the cap and the pre-diffuser. This invention, by introducing a motion mechanism, achieves precise displacement of the cap, thus providing sufficient operating space for the nozzle and optimizing the aerodynamic performance of the diffuser.

Description

Technical Field

[0001] This invention relates to the field of aero-engine combustion chamber technology, and more specifically to a combustion chamber structure with a movable cap. Background Technology

[0002] The combustion chamber is a core component of an aero-engine. Its inlet cap and diffuser together form the aerodynamic channel for the incoming airflow, slowing and pressurizing it, directly affecting airflow separation, total pressure loss coefficient, and the quality of the flow field entering the combustion chamber. With the development of low-carbon / zero-carbon power technologies, new fuels such as hydrogen are increasingly being used in gas turbines and aero-engines. Due to hydrogen's low volumetric energy density and wide combustibility limits, the combustion chamber requires nozzles with larger flow rates and specific structures (such as diffusers), resulting in a significantly larger radial dimension than traditional aviation kerosene nozzles.

[0003] For large-size hydrogen fuel nozzles, the design of the cap structure, while ensuring the aerodynamic performance of the combustion chamber, often results in severe radial interference between the cap's assembly and disassembly path and the fixed edge of the cap. To replace or repair the nozzle, it is often necessary to disassemble the entire cap and even the diffuser assembly, significantly increasing the difficulty of nozzle assembly and maintenance. Furthermore, once the traditional fixed cap is assembled, its relative position to the diffuser cannot be changed. In actual testing, when poor diffuser performance is found due to manufacturing deviations or changes in operating conditions, online adjustments are impossible, requiring the redesign and remanufacturing of the entire cap or diffuser component, leading to long development cycles and high costs. Therefore, the existing fixed cap structure is insufficient to meet the assembly, maintenance, and performance optimization requirements of next-generation large-size nozzle combustion chambers, urgently necessitating a new cap design to address these issues. Summary of the Invention

[0004] In view of this, this application provides a combustion chamber structure with a movable cap to solve the technical problems of existing fixed caps being unable to accommodate the disassembly and assembly of large-sized nozzles and the lack of adjustable aerodynamic performance. This structural design aims to achieve precise displacement of the cap by introducing a motion mechanism, thereby providing sufficient operating space for the nozzle and enabling the adjustment and optimization of the diffuser's aerodynamic performance to meet the needs of rapid nozzle disassembly and assembly and diffuser aerodynamic performance optimization in the era of new fuels.

[0005] This application provides the following technical solution: a combustion chamber structure with a movable cap, comprising:

[0006] Combustion chamber casing; The flame tube is disposed inside the combustion chamber casing; A pre-diffuser is located upstream of the air inlet of the flame tube; A cap is axially movable at the air inlet end of the flame tube, providing space for nozzle installation by axial movement, and regulating the airflow field by being positioned opposite the pre-diffuser; A connecting rod, the first end of which is connected to the cap; A pull rod, the first end of which is connected to the second end of the connecting rod, the second end of which extends from the mounting seat on the combustion chamber casing to the outside; Specifically, by axially moving the pull rod, the connecting rod is driven to move the cap relative to the flame tube axially, thereby changing the relative position between the cap and the pre-diffuser.

[0007] According to one embodiment of the present invention, the outer surface of the cap is provided with evenly distributed connecting lugs, and the first end of the connecting rod is hinged to the connecting lugs by a pin.

[0008] According to one embodiment of the present invention, the cap has a reference hole circumferentially opened on its surface for adjusting the air flow distribution of the nozzle, and the reference hole has a slot for easy disassembly and assembly of the nozzle.

[0009] According to one embodiment of the present invention, a locking mechanism for locking the position of the pull rod is provided on the mounting base of the combustion chamber casing.

[0010] According to one embodiment of the present invention, the locking mechanism includes a lock nut and a clamping cover plate. The lock nut is threaded onto the pull rod, and the clamping cover plate is sleeved on the pull rod and fixedly connected to the mounting base by bolts to clamp and fix the lock nut.

[0011] According to one embodiment of the present invention, a sealing structure is further provided between the mounting base and the pull rod. The sealing structure includes a sealing ring, a gasket, and an asbestos rope. The sealing ring is sleeved on the pull rod and contacts the spherical surface of the pull rod. The gasket is provided between the clamping cover plate and the mounting base. The asbestos rope is filled between the clamping cover plate and the anti-loosening nut.

[0012] According to one embodiment of the present invention, there is an adjustable axial gap between the air inlet end face of the cap and the air inlet end face of the flame tube.

[0013] According to one embodiment of the present invention, the second end of the connecting rod is hinged to the first end of the pull rod by a pin.

[0014] Compared with the prior art, the beneficial effects that at least one technical solution adopted in the embodiments of this specification can achieve include at least: 1. The structural design of this invention greatly facilitates nozzle disassembly and assembly, and reduces the difficulty of assembly and maintenance. When it is necessary to install or disassemble a large-size hydrogen fuel nozzle, the cap can be moved to a pre-set "maintenance position" through the motion mechanism, providing sufficient radial and axial operating space for the nozzle, realizing direct and quick disassembly and assembly of the nozzle without disassembling the cap or diffuser, and significantly improving maintenance efficiency.

[0015] 2. This invention achieves aerodynamic performance adjustment and optimization: by precisely controlling the axial position of the cap, the relative distance and channel area between the cap lip and the pre-diffuser can be changed in real time, thereby actively controlling airflow separation and reducing the total pressure loss of the diffuser. During the experiment, researchers can adjust as they go, quickly finding the optimal aerodynamic settings and shortening the research and development cycle. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a combustion chamber structure with a movable cap according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the cap structure according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the tie rod structure according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the tie rod mounting base according to an embodiment of the present invention; Figure 5 This is a schematic diagram of nozzle installation according to an embodiment of the present invention; Figure 6 This is a schematic diagram illustrating the axial movement principle of the cap according to an embodiment of the present invention; Among them, 001-combustion chamber casing, 002-injection unit, 003-flame tube, 004-splash deflector, 005-transfer section, 006-cap cover, 007-connecting rod, 008-pull rod, 009-anti-loosening nut, 010-pressure cover plate, 011-sealing ring, 012-gasket, 013-cap center line, 014-combustion chamber center line. Detailed Implementation

[0018] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0019] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] This invention provides a combustion chamber structure with a movable cap. The invention utilizes a linkage mechanism to control the axial feed of the cap, greatly facilitating the repeated installation and disassembly of large-size nozzles, reducing assembly and maintenance difficulty. Precise control of the cap's axial position via the linkage mechanism facilitates aerodynamic performance adjustment and optimization, meeting the assembly, maintenance, and performance optimization requirements of next-generation large-size nozzle combustion chambers. Specifically, as... Figure 1 As shown, the combustion chamber structure consists of a combustion chamber housing 001, an injection unit 002, a flame tube 003, a splash guard 004, a transition section 005, a cap 006, a connecting rod 007, and a tie rod 008.

[0021] The structural diagram of the cap 006 is as follows: Figure 2 As shown, the number of openings in the cap is consistent with the number of nozzles. A reference hole is opened on the cap surface along the nozzle mounting axis, and a nozzle disassembly and assembly slot is provided to ensure that the cap moves along the combustion chamber axis while the nozzle is fixed. The outer surface of the cap is provided with evenly distributed connecting lugs, which are connected to the connecting rod 007 by a pin. The lugs are distributed in the middle of two adjacent reference holes and are symmetrically distributed along the overall center. Based on this structure, the opening area of ​​the cap is not affected by the nozzle diameter. Under large-size nozzles, the design space can be widened, and the performance parameters such as the total pressure recovery coefficient of the combustion chamber can be improved. At the same time, flow separation is reduced to a certain extent.

[0022] The structural diagram of tie rod 008 is as follows: Figure 3 As shown, its lower end is connected to the connecting rod 007 via a pin and extends from the mounting base on the casing; the upper end is a stepped shaft with a connecting hole at the top to facilitate connection with the tooling and ensure that the center line of the cap is collinear with the overall center line of the combustion chamber.

[0023] The structural diagram of the tie rod mounting base is shown below. Figure 4As shown, anti-loosening nut 009, clamping cover plate 010, sealing ring 011, and gasket 012 are arranged respectively. During installation, the sealing ring 011 and gasket 012 are fitted onto the pull rod 008, and then the anti-loosening nut 009 is installed on the pull rod 008. After completing the nozzle assembly and determining the cap position, the clamping cover plate 010 is used to install the anti-loosening nut 009, thus fixing the pull rod 008. The sealing ring 011 and the pull rod 008 make contact through a spherical surface. A gasket is installed between the clamping cover plate 010 and the mounting base. At the same time, asbestos rope is placed between the clamping cover plate 010 and the anti-loosening nut 009 to achieve a sealing effect.

[0024] like Figure 5 As shown, the nozzle installation and adjustment process is as follows: 1. Initial preparation: First, extend the pull rod 008 from the housing mounting base, and install the sealing ring 011, gasket 012 and anti-loosening nut 009 on the pull rod 008 in sequence. At this time, the pull rod 008 can move freely along the pull rod axis. Then, complete the installation and fixation of the flame tube 003.

[0025] 2. Move to maintenance position: Before installing the nozzle assembly, move the tie rod 008 to drive the connecting rod 007, which in turn moves the cap 006 towards the front diffuser, providing sufficient space for nozzle installation. During the movement, ensure that the cap 006 and connecting rod 007 do not collide with or damage the front diffuser. Simultaneously, ensure that the tie rod 008 moves the same distance axially as much as possible, thereby ensuring that the centerline of the cap 006 is collinear with the overall centerline of the combustion chamber.

[0026] The "maintenance position" refers to the position whereby the cap 006 can be moved away from the flame tube 003 body to create a clearance space between the cap 006 and the flame tube 003 body for nozzle assembly and disassembly.

[0027] 3. Install the nozzle: Insert the nozzle from the nozzle mount and slide it to the designated position.

[0028] 4. Move to the working position: Move the lever 008 again to move the cap 006 toward the flame tube 003. During the movement, try to ensure that the center line of the cap is collinear with the center line of the combustion chamber. Ideally, the cap 006 can be flush with the end face of the flame tube 003. At this time, the anti-loosening nut 009 should be in contact with the washer 012.

[0029] 5. Fixing and sealing: Place the clamping cover plate 010 on the pull rod 008, place an asbestos rope between the clamping cover plate 010 and the anti-loosening nut 009, and then use bolts to clamp and fix the clamping cover plate 010 to complete the locking and sealing of the pull rod 008.

[0030] 6. Aerodynamic performance adjustment: During testing or use, the gap between the cap 006 and the flame tube 003 can be adjusted by controlling the movement distance of the pull rod 008, thereby regulating the channel area and relative distance between the lip of the cap 006 and the front diffuser to optimize performance parameters such as the total pressure loss of the combustion chamber.

[0031] like Figure 6 As shown, the principle of axial movement of the cap in this invention is as follows: In the annular combustion chamber, a corresponding number of connecting rods 007 and tie rods 008 are connected to the lugs of the cap 006. During movement, the tie rods 008 move along the axis of the mounting holes in the combustion chamber casing 001, and the lugs are symmetrically distributed along the center of the cap. Therefore, the distance of the tie rods can be adjusted by tooling to ensure that the center line 013 of the cap and the center line 014 of the combustion chamber are collinear. In a single plane, since the connecting rod 007 has a fixed length, the cap can be equivalent to a flat plate. Figure 6 As can be seen, the axial distance of the cap's movement can be controlled by adjusting the lever.

[0032] This invention utilizes a linkage mechanism to control the axial feed of the cap, moving the cap towards the diffuser to ensure the nozzle installation distance. After the nozzle is installed, the linkage structure is used to move the cap to a designated plane. Finally, the pull rod is fixed and sealed at the mounting base.

[0033] 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 combustor structure with a movable shroud, characterized by, include: Combustion chamber casing; The flame tube is disposed inside the combustion chamber casing; A pre-diffuser is located upstream of the air inlet of the flame tube; A cap is axially movable at the air inlet end of the flame tube, providing space for nozzle installation by axial movement, and regulating the airflow field by being positioned opposite the pre-diffuser; A connecting rod, the first end of which is connected to the cap; A pull rod, the first end of which is connected to the second end of the connecting rod, the second end of which extends from the mounting seat on the combustion chamber casing to the outside; Specifically, by moving the pull rod, the connecting rod is driven to move the cap axially relative to the flame tube, thereby changing the relative position between the cap and the pre-diffuser.

2. The combustor structure with a movable shroud according to claim 1, wherein The outer surface of the cap is provided with evenly distributed connecting lugs, and the first end of the connecting rod is hinged to the connecting lugs by a pin.

3. The combustor structure with a movable shroud according to claim 1, wherein The cap has a reference hole circumferentially opened on its surface for adjusting the air flow distribution of the nozzle, and the reference hole has a slot for easy nozzle disassembly and assembly.

4. The combustor structure with a movable shroud according to claim 1, wherein The mounting base of the combustion chamber casing is provided with a locking mechanism for locking the axial position of the pull rod.

5. The combustion chamber structure with a movable cap according to claim 4, characterized in that, The locking mechanism includes a lock nut and a clamping cover plate. The lock nut is threaded onto the pull rod, and the clamping cover plate is sleeved on the pull rod and fixedly connected to the mounting base by bolts to clamp and fix the lock nut.

6. The combustion chamber structure with a movable cap according to claim 5, characterized in that, It also includes a sealing structure disposed between the mounting base and the pull rod, the sealing structure including a sealing ring, a gasket and an asbestos rope; the sealing ring is sleeved on the pull rod and contacts the spherical surface of the pull rod; the gasket is disposed between the clamping cover plate and the mounting base; the asbestos rope is filled between the clamping cover plate and the anti-loosening nut.

7. The combustion chamber structure with a movable cap according to claim 1, characterized in that, The air inlet end face of the cap and the air inlet end face of the flame tube have an adjustable axial gap.

8. The combustion chamber structure with a movable cap according to claim 1, characterized in that, The second end of the connecting rod is hinged to the first end of the pull rod by a pin.

Images