Fan outlet guide vane, fan outlet guide vane assembly and assembling method thereof

Abstract

The fan outlet guide vane assembly facilitating repeated assembling operation comprises an intermediate outer casing mounting part, an intermediate inner casing mounting part and a plurality of outlet guide vanes located between the intermediate outer casing mounting part and the intermediate inner casing mounting part. The blade tops of the outlet guide blades are connected with the intermediate outer casing mounting portion through radial connecting devices, the blade roots of the outlet guide blades are connected with the intermediate inner casing mounting portion through axial connecting devices, and circumferential gaps exist between edge plates of the adjacent outlet guide blades in the circumferential direction. The fan outlet guide vane assembly further comprises a plurality of circumferential connecting devices, the adjacent outlet guide vanes in the circumferential direction are connected at the blade roots through the circumferential connecting devices, and the circumferential gaps are kept. The fan outlet guide vane is suitable for the fan outlet guide vane assembly. The assembly method suitable for the fan outlet guide vane assembly is high in disassembly and assembly efficiency.

Description

Technical Field

[0001] The invention relates to a fan outlet guide vane of a turbofan engine or a gas turbine, a fan outlet guide vane assembly and an assembly method thereof. Background Art

[0002] The axial-flow turbomachinery, with the axial-flow aircraft engine as a typical example, is composed of high-pressure and low-pressure dual rotors, in which the low-pressure rotor includes the inlet low-pressure fan and the outlet low-pressure turbine. The intermediate inner casing is connected between the low-pressure fan and the high-pressure compressor. It is one of the engine's load-bearing frames, bearing the main load of the engine and transmitting it through the mounting node. The outlet guide vane is installed on the intermediate inner casing, and its main function is to guide the outlet airflow and bear the radial load of the engine. During the operation of the engine, due to the effect of the external duct airflow, the outlet guide vane is subject to a large aerodynamic load, and at the same time, foreign matter in the airflow flows through the outlet guide vane. During the service of the engine, due to the continuous impact of foreign objects such as airflow and gravel, the outlet guide vane needs to be regularly maintained and replaced. Therefore, the assembly and disassembly of the outlet guide vane is very critical.

[0003] A single outlet guide vane is tightened on the outer casing and the inner casing by bolts at the top and bottom ends. During assembly, the outlet guide vane is first assembled with the outer casing as a whole, and then the entire thing is pushed in and assembled on the outer flange edge of the inner casing. During the design process of the outlet guide vane, due to processing deformation, accumulation of assembly clearance tolerances, etc., assembly interference is easily caused, so a gap is left at the lower edge plate. During multiple actual assembly or disassembly processes, this gap will cause the blade to shake during assembly, which is very unfavorable for assembly positioning and protection between blades, and it is also difficult to ensure the consistency of the circumferential position of the outlet guide vane in the flow channel. Summary of the invention

[0004] An object of the present invention is to provide a fan outlet guide vane assembly that facilitates repeated assembly of the fan outlet guide vanes.

[0005] Another object of the present invention is to provide a fan outlet guide vane, which is suitable for the aforementioned fan outlet guide vane assembly.

[0006] An object of the present invention is to provide an assembly method of a fan outlet guide vane assembly, which has high assembly and disassembly efficiency.

[0007] According to one aspect of the present invention, a fan outlet guide vane assembly comprises an intermediate outer casing mounting portion, an intermediate inner casing mounting portion and a plurality of outlet guide vanes located between the intermediate outer casing mounting portion and the intermediate inner casing mounting portion, wherein the blade top of the outlet guide vane is connected to the intermediate outer casing mounting portion via a radial connecting device, the blade root of the outlet guide vane is connected to the intermediate inner casing mounting portion via an axial connecting device, and a circumferential gap exists between edge plates of the circumferentially adjacent outlet guide vanes, wherein the fan outlet guide vane assembly further comprises a plurality of circumferential connecting devices, and the circumferentially adjacent outlet guide vanes are connected at the blade root via the circumferential connecting devices, and the circumferential gap is maintained.

[0008] In one embodiment, the circumferential connection device connects the blade roots between the outlet guide vanes adjacent to each other in the circumferential direction on the axial side.

[0009] In one embodiment, the circumferential connection device connects the blade roots between the outlet guide vanes adjacent in the circumferential direction upstream or downstream of the blade root.

[0010] In one embodiment, the circumferential connection device includes a connection gasket and a circumferential fastener, and two ends of the connection gasket are respectively connected to the blade roots of adjacent outlet guide vanes through the circumferential fastener.

[0011] In one embodiment, the axial connection device includes an axial fastener, which passes through the connection gasket to connect the blade root and the intermediate inner casing mounting portion.

[0012] In one embodiment, the circumferential fastener is a threaded connector, and the outlet guide vane has a prefabricated threaded hole at the blade root for connection with the threaded connector.

[0013] In one embodiment, the circumferential gap is filled by a seal.

[0014] According to another aspect of the present invention, a fan outlet guide vane is used in any of the above fan outlet guide vane assemblies, and has an adaption structure at the blade root that is suitable for connecting with the outlet guide vanes adjacent to the circumferential direction through the circumferential connection device.

[0015] According to another aspect of the present invention, a method for assembling a fan outlet guide vane assembly uses the fan outlet guide vane assembly to assemble the outlet guide vanes into a whole with the intermediate outer casing mounting portion via the radial connecting device, and then connects the circumferentially adjacent outlet guide vanes at the blade roots via the circumferential connecting device, and then pushes the whole to the intermediate inner casing mounting portion, and connects the blade roots of the outlet guide vanes to the intermediate inner casing mounting portion via the axial connecting device.

[0016] According to an embodiment of the present invention, a circumferential connecting device is added between each outlet guide vane. The circumferential position of a circle of outlet guide vanes is effectively positioned through the connection between the circumferential connecting device and the outlet guide vanes, thereby facilitating the repeated assembly of the fan outlet guide vanes and improving the efficiency of disassembly and assembly of the outlet guide vanes during maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0018] Figure 1 It is a partial schematic diagram of a turbofan engine;

[0019] Figure 2 is a schematic diagram of installing the fan outlet guide vane assembly;

[0020] Figure 3 is a partial view of a fan outlet guide vane assembly without a circumferential connection device;

[0021] Figure 4 yes Figure 3 A partial enlarged view of the blade root area of ​​the middle outlet guide vane;

[0022] Figure 5 is a partial view of a fan outlet guide vane assembly using a circumferential connection device;

[0023] Figure 6 yes Figure 5 BB cross-sectional view;

[0024] Figure 7 yes Figure 5 CC cross-sectional view. DETAILED DESCRIPTION

[0025] Reference will now be made in detail to embodiments of the present invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided to explain the present invention, not to limit the present invention. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made in the present invention without departing from the scope or spirit of the present invention. For example, a feature illustrated or described as part of one embodiment may be used together with another embodiment to produce yet another embodiment. Therefore, the present invention is intended to cover these modifications and variations within the scope of the appended claims and their equivalents.

[0026] The terms "upstream" and "downstream" refer to relative directions relative to the flow of a fluid in a fluid path. For example, "upstream" refers to the direction from which the fluid is flowing, and "downstream" refers to the direction toward which the fluid is flowing.

[0027] The "outlet guide vane" is used in the outer duct of a turbofan engine or a gas turbine to guide the outlet airflow.

[0028] The "intermediate outer casing mounting portion" is a structure of the intermediate outer casing for mounting outlet guide vanes.

[0029] The "intermediate inner casing mounting portion" is a structure of the intermediate inner casing used to mount the outlet guide vane, and a common example is a flange edge mounted on the intermediate inner casing.

[0030] Directional terms such as "radial", "circumferential", and "axial" are referenced to the central axis of the rotating machine.

[0031] Figure 1 The fan and low-pressure compressor of the turbofan engine are shown, while the high-pressure compressor, combustion chamber, high-pressure turbine driving the compressor, low-pressure turbine driving the fan, and exhaust system of the turbofan engine are not shown in the figure. The fan includes a fan rotor composed of fan blades 1, fan blade disks 2, and fan shafts 6. The fan rotor can be a single-stage or multi-stage blade. After the air flows through the fan, it is divided into two paths: one is the inner airflow, the air continues to be compressed by the low-pressure compressor 5, and the high-pressure compressor further compresses it, and it is mixed with fuel in the combustion chamber and burned. The gas expands through the turbine and the nozzle, and the gas is discharged from the tail nozzle at a high speed to generate thrust, and the gas is discharged from the nozzle; the other is the outer duct airflow, and the air after the fan is directly discharged into the atmosphere through the outer duct or discharged from the nozzle together with the inner duct gas. The outlet guide vane 4 is installed at the outlet position of the outer duct.

[0032] The outlet guide vane 4 includes a blade body 41, a blade top 42 and a blade root 43, and an edge plate 44 is arranged between the blade body 41 and the blade root 43. The edge plate 44 is also called a platform, and its radial outer surface is used as the airflow flow path surface at the outlet position of the outer duct. The blade structure on the radial inner side of the edge plate 44 is the blade root 43, and the blade root 43 includes two mounting edges.

[0033] like Figures 1 to 4 As shown, the intermediate outer casing 3 includes an intermediate outer casing mounting portion 31. The intermediate inner casing 8 includes an intermediate inner casing mounting portion 81. The radial connecting device 32 is exemplified as a bolt in the figure. The axial connecting device 10 is also exemplified as a bolt. The blade top 42 of the outlet guide vane 4 is connected to the outer casing mounting portion 31 through the radial connecting device 32, and the blade root 43 is connected to the intermediate inner casing mounting portion 81 through the axial connecting device 10. Due to the accumulation of processing deformation and assembly clearance tolerance, each outlet guide vane 4 has a circumferential gap 12 of 1-2 mm along the circumferential position to facilitate the actual assembly operation. The circumferential gap 12 is filled with a seal, which can effectively prevent the airflow from entering the intermediate inner casing.

[0034] In the actual working process, since the blade tip and the blade root are connected and fixed, the outlet guide vane 4 will not move circumferentially. However, in the assembly and disassembly process, after the axial connection device 10 is loosened, when only the radial connection device 32 exists, a circle of outlet guide vanes will be displaced circumferentially. That is, in the actual multiple assembly or disassembly process, the circumferential gap 12 between the outlet guide vanes 4 will cause the blades to shake during the assembly process, which is very unfavorable for the assembly positioning and the protection between the blades. It is difficult to ensure that the outlet guide vanes are located in the circumferential position of the flow channel. For example, the circumferential position of each outlet guide vane 4 relative to the intermediate inner casing mounting portion 81 is pre-designed and fixed, and the precision requirement is very high. If there is shaking, it is necessary to manually adjust the position of a circle of outlet guide vanes one by one, and the assembly efficiency is therefore greatly limited.

[0035] The terms “radial connection device”, “axial connection device” and “circumferential connection device” are connection devices whose main restraining direction is radial, axial or circumferential, respectively.

[0036] like Figure 5 As shown, the fan outlet guide vane assembly further includes a plurality of circumferential connection devices 9, and the outlet guide vanes 4 adjacent in the circumferential direction are connected at the blade roots by the circumferential connection devices 9, and a circumferential gap 12 is maintained. By adding circumferential connection devices 9 between each outlet guide vane 4 and connecting the circumferential connection devices 9 with the outlet guide vanes 4, the circumferential position of a circle of outlet guide vanes 4 is effectively located, thereby improving the disassembly and assembly efficiency during aircraft engine maintenance.

[0037] like Figure 5 As shown, the circumferential connecting device 9 connects the blade roots 43 between the circumferentially adjacent outlet guide vanes 4 at the axial side of the outlet guide vane 4 . Figure 2 The arrow in the figure shows the installation direction of the outlet guide vane 4. The circumferential connecting device 9 is connected to the blade root 43 on the axial side, and the installation edge 431 or 432 of the blade root 43 can be directly used. In this way, the structural change of the outlet guide vane 4 is very small, and the manufacturing process remains almost unchanged.

[0038] Figure 6 and Figure 7 It is shown that the circumferential connection device 9 connects the blade roots 43 between the circumferentially adjacent outlet guide vanes 4 in the axial upstream. It is also understandable that the blade roots 43 between the circumferentially adjacent outlet guide vanes 4 in the axial downstream can also be connected by the circumferential connection device 9.

[0039] Figure 7 yes Figure 5 The CC section view of FIG. 1 shows a section through the circumferential connection device. Figure 7As shown, the circumferential connection device 9 includes a connection gasket 91 and a circumferential fastener 11. Both ends of the connection gasket 91 are connected to the blade root 43 of the adjacent outlet guide vane 4 through the circumferential fastener 11, and the specific connection position as shown in the figure is at the installation edge 431 of the blade root 43.

[0040] Figure 6 yes Figure 5 The BB section view of the axial connection device is cut through. Figure 6 As shown, the axial connection device 10 includes an axial fastener, which passes through the connection gasket 91 to connect the blade root 43 and the intermediate inner casing mounting portion 81. The axial fastener is exemplified as a bolt and nut assembly in the figure.

[0041] exist Figure 7 In the embodiment, the circumferential fastener 11 is exemplified as a threaded connector, and the outlet guide vane 4 has a prefabricated threaded hole at the blade root 43 for connection with the threaded connector. The prefabricated threaded hole can be machined after the outlet guide vane 4 is integrally formed.

[0042] In the aforementioned embodiment, the fan outlet guide vane 4 can be formed by structurally improving the existing outlet guide vane of the axial flow aircraft engine, that is, the blade root has an adapting structure suitable for connecting with the outlet guide vanes 4 adjacent in the circumferential direction through the circumferential connecting device 9, and an example of the adapting structure is a prefabricated threaded hole, but it is not limited thereto. In this way, the purpose of enhancing the stability of the outlet guide vane 4 during the disassembly and assembly process is achieved by using different configurations.

[0043] Based on the above embodiments, a method for assembling a fan outlet guide vane assembly is combined with Figure 2 and Figure 5 First, the outlet guide vane 4 is assembled into a whole with the intermediate outer casing mounting portion 31 or the entire intermediate outer casing 3 through the radial connecting device 32, and then the outlet guide vanes 4 adjacent to each other in the circumferential direction are connected at the blade root through the circumferential connecting device 9, and then the whole is assembled according to Figure 2 The guide vane 4 is pushed to the intermediate inner casing mounting portion 81 in the direction indicated by the arrow, and the blade root 43 of the outlet guide vane 4 is connected to the intermediate inner casing mounting portion 81 through the axial connecting device 10. In this way, after the axial connecting device 10 is loosened, the outlet guide vane can still be assembled and disassembled as a whole due to the connecting effect of the circumferential connecting device 9, and the blades are relatively stable and the relative positions can be guaranteed. Therefore, during the assembly and disassembly process, the outer casing and the outlet guide vane 4 can be assembled and disassembled as a whole, which effectively improves the disassembly efficiency during aircraft engine maintenance, shortens the maintenance time, and indirectly reduces the maintenance cost.

[0044] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A fan outlet guide vane assembly, comprising an intermediate outer casing mounting portion, an intermediate inner casing mounting portion, and a plurality of outlet guide vanes located between the intermediate outer casing mounting portion and the intermediate inner casing mounting portion, wherein the blade tip of the outlet guide vane is connected to the intermediate outer casing mounting portion via a radial connection device, the blade root of the outlet guide vane is connected to the intermediate inner casing mounting portion via an axial connection device, and a circumferential gap exists between the edge plates of the circumferentially adjacent outlet guide vanes, characterized in that: The fan outlet guide vane assembly further comprises a plurality of circumferential connection devices, and the outlet guide vanes adjacent to each other in the circumferential direction are connected at the blade roots by the circumferential connection devices, and the circumferential gap is maintained.

2. The fan outlet guide vane assembly according to claim 1, characterized in that: The circumferential connecting device connects the blade roots between the outlet guide vanes adjacent to each other in the circumferential direction on the axial side.

3. The fan outlet guide vane assembly according to claim 2, characterized in that: The circumferential connecting device connects the blade roots between the outlet guide vanes adjacent in the circumferential direction upstream or downstream of the blade root.

4. The fan outlet guide vane assembly according to any one of claims 1 to 3, characterized in that: The circumferential connection device comprises a connection gasket and a circumferential fastener, and two ends of the connection gasket are respectively connected to the blade roots of adjacent outlet guide vanes through the circumferential fastener.

5. The fan outlet guide vane assembly according to claim 4, characterized in that: The axial connection device includes an axial fastener, which passes through the connection gasket to connect the blade root and the intermediate inner casing mounting portion.

6. The fan outlet guide vane assembly according to claim 4, characterized in that: The circumferential fastener is a threaded connector, and the outlet guide vane has a prefabricated threaded hole at the blade root for connection with the threaded connector.

7. The fan outlet guide vane assembly according to claim 1, wherein: The circumferential gap is filled by a seal.

8. A fan outlet guide vane, used for the fan outlet guide vane assembly according to any one of claims 1 to 7, characterized in that: The blade root is provided with an adapting structure suitable for connecting with the outlet guide vanes adjacent to the circumferential direction through the circumferential connecting device.

9. A method for assembling a fan outlet guide vane assembly, using the fan outlet guide vane assembly according to any one of claims 1 to 7, characterized in that: The outlet guide vane is assembled into a whole with the intermediate outer casing mounting portion through the radial connecting device, and then the outlet guide vanes adjacent to each other in the circumferential direction are connected at the blade roots through the circumferential connecting device, and then the whole is pushed to the intermediate inner casing mounting portion, and the blade roots of the outlet guide vanes are connected to the intermediate inner casing mounting portion through the axial connecting device.

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