An Angle-adjustable Airflow Incentor for Aeroengine Blades

Abstract

The present invention provides an air flow exciter for an aeroengine blade with adjustable angle, comprising: an adjusting piece assembly, the adjusting piece assembly includes a plurality of adjusting pieces with the same structure and stacked in sequence, and an arc-shaped adjusting part is arranged between two adjacent adjusting pieces, and the arc-shaped adjusting part is used for adjusting the angle between two adjacent adjusting pieces; a connecting assembly, the connecting assembly is used to pass through the connecting holes on each adjusting piece and fix the plurality of adjusting pieces to form an air flow exciter for an aeroengine blade. The air flow exciter designed by the present invention can adjust the angle between adjacent adjusting pieces according to test requirements to simulate complex bending and sweeping forms of the excited blades, thereby solving the problems of extended test cycle and increased test cost caused by the need to redesign and process different air flow exciters due to different shapes of the excited blades.

Description

Technical Field

[0001] The present invention relates to the technical field of aero-engine blade fatigue tests, and particularly to an airflow exciter for aero-engine blades with adjustable angles. Background Art

[0002] The blade is one of the key components of an aero-engine, and its structural strength has an important impact on the performance and even safety of the engine. In order to enable modern high-performance aero-engines to have a higher thrust-to-weight ratio, one of the key technologies adopted is to increase the unit frontal area flow rate and stage pressure ratio of the fan / compressor components on the premise of not reducing or even increasing the stage efficiency. It usually reduces the number of stages and blades, so in terms of structure, it tends to adopt complex curved and swept blade shapes, as well as designs such as small aspect ratios and integral bladed disks. Although the above technologies can greatly improve the aerodynamic performance of the blades, they will also deteriorate the aerodynamic excitation environment, making the problem of high-cycle fatigue failure caused by fluid-induced vibration of the blades increasingly prominent. Especially, the rotating blades also have to bear the low-cycle fatigue caused by centrifugal loads during the cycle of aircraft takeoff and landing. The probability of blade failure caused by the combined high- and low-cycle fatigue under the two actions increases significantly.

[0003] Currently, in the process of aero-engine blade design, the high-cycle fatigue test technology is one of the most important means to solve the high-cycle fatigue problem of blades. The vibration characteristics test of a single blade can be completed on a conventional vibration table, but this experiment cannot simulate the actual working conditions of the blade in the engine, especially the problems of the excitation source and the loading of centrifugal loads. In order to simulate the high-cycle fatigue of the blade under actual working conditions as much as possible, the most cost-effective method currently is to conduct high-cycle fatigue tests on a rotating test bench. On the one hand, the dynamic rotating test bench can simulate the engine speed, and on the other hand, an airflow exciter can be used to simulate the wake of the previous-stage blade, so as to realize the high-cycle fatigue excitation loading of the blade.

[0004] However, the current airflow exciter mainly adopts the single L-shaped structure shown in Figure 1 It adjusts the excitation order by the number of circumferentially evenly distributed airflow exciters. However, this kind of airflow exciter cannot simulate the wake of curved and swept blades. Especially when the airflow excites the blade and changes, since its trailing edge shape changes accordingly, it is necessary to design and process a new airflow exciter for loading. Especially when the excitation order is high and the number of airflow exciters required is large, the test cycle consumed is long and the processing cost is high.

[0005] Therefore, it is necessary to improve the existing airflow exciter to solve the above problems. Summary of the Invention

[0006] The object of the present invention is to solve the problem that the existing air flow exciters cannot simulate the wakes of curved and swept blades. An air flow exciter for an aeroengine blade with adjustable angles is designed. This air flow exciter can simulate the complex curved and swept shapes of different exciting blades, and can greatly reduce the test cycle and test cost.

[0007] The technical solution for achieving the object of the invention is as follows: An air flow exciter for an aeroengine blade with adjustable angles, comprising:

[0008] An adjusting piece assembly, the adjusting piece assembly includes a plurality of adjusting pieces with the same structure and stacked in sequence, and an arc-shaped adjusting part is provided between two adjacent adjusting pieces. The arc-shaped adjusting part is used to adjust the angle between two adjacent adjusting pieces;

[0009] A connecting component, the connecting component is used to pass through the connecting holes on each adjusting piece and fix the plurality of adjusting pieces to form an air flow exciter for an aeroengine blade.

[0010] In an improved embodiment, the arc-shaped adjusting part includes:

[0011] An arc-shaped groove, the arc-shaped groove is located on one side of the adjusting piece, and the center of the arc-shaped groove coincides with the center of the connecting hole;

[0012] A boss, the boss is located on the other side of the adjusting piece;

[0013] When two adjacent adjusting pieces are assembled, the boss of the previous adjusting piece moves in the arc-shaped groove of the next adjusting piece, or the boss of the next adjusting piece moves in the arc-shaped groove of the previous adjusting piece.

[0014] In an improved embodiment, the arc-shaped groove includes a plurality of circular arc-shaped grooves connected in sequence according to a set adjustment angle, and the width of the connection part between two adjacent circular arc-shaped grooves is equal to the diameter of the boss.

[0015] Preferably, the set adjustment angle is 3° - 15°, that is, the angle adjustment range between two adjacent adjusting pieces is 3° - 15°.

[0016] In an improved embodiment, the adjusting piece is an L-shaped adjusting piece, and the connecting hole is located at the corner position of the L-shaped adjusting piece.

[0017] In an improved embodiment, the connecting component includes a bolt and a nut. The bolt passes through the connecting holes of each adjusting piece in sequence and is fixed by the nut.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: The angle-adjustable air flow exciter for aero-engine blades designed by the present invention is used for high-cycle fatigue gas excitation loading during the high-cycle and even high-low cycle composite fatigue tests of aero-engine blades. It can adjust the angle between adjacent adjusting pieces according to test requirements to simulate complex bending and sweeping shapes of the excited blades, thereby solving the problems of extended test cycles and increased test costs caused by the need to redesign and process different air flow exciters due to different shapes of the excited blades. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for the description of the embodiments.

[0020] Figure 1 Schematic diagram of an existing L-shaped air flow exciter;

[0021] Figure 2 Assembly schematic diagram of the angle-adjustable air flow exciter for aero-engine blades of the present invention;

[0022] Figure 3 Schematic diagram of the arc-shaped groove in the adjusting piece in the specific embodiment;

[0023] Figure 4 Schematic diagram of the boss in the adjusting piece in the specific embodiment

[0024] Wherein, 1. Adjusting piece; 11. Connecting hole; 12. Arc-shaped groove; 13. Boss; 121. Circular arc-shaped groove; 2. Bolt; 3. Nut. SPECIFIC EMBODIMENTS

[0025] The present invention will be further described below in conjunction with specific embodiments, and the advantages and features of the present invention will become clearer as the description progresses. However, these embodiments are exemplary only and do not constitute any limitation to the scope of the present invention. Those skilled in the art should understand that modifications or substitutions can be made to the details and forms of the technical solutions of the present invention without departing from the spirit and scope of the present invention, but these modifications and substitutions all fall within the protection scope of the present invention.

[0026] The present specific embodiment provides an angle-adjustable air flow exciter for aero-engine blades. The air flow exciter includes an adjusting piece assembly and a connecting assembly, and the connecting assembly is used to fix the adjusted adjusting piece assembly according to test requirements.

[0027] See Figure 2 As shown, the adjusting piece assembly includes a plurality of adjusting pieces 1 with the same structure and stacked in sequence, and an arc-shaped adjusting part is provided between adjacent adjusting pieces 1, and the arc-shaped adjusting part is used to adjust the angle between adjacent adjusting pieces 1.

[0028] See Figures 2 to 4 As shown, the connecting component is used to pass through the connecting holes 11 on each of the adjusting pieces 1 and fix a plurality of the adjusting pieces 1 to form an air flow actuator for an aeroengine blade.

[0029] In an improved embodiment, see Figure 3 and Figure 4 As shown, the arc-shaped adjusting portion includes:

[0030] An arc-shaped groove 12, the arc-shaped groove 12 is located on one side of the adjusting piece 1, and the center of the circle of the arc-shaped groove 12 coincides with the center of the circle of the connecting hole 11.

[0031] A boss 13, the boss 13 is located on the other side of the adjusting piece 1;

[0032] When two adjacent adjusting pieces 1 are assembled, the boss 13 of the previous adjusting piece 1 moves in the arc-shaped groove 12 of the next adjusting piece 1, or the boss 13 of the next adjusting piece 1 moves in the arc-shaped groove 12 of the previous adjusting piece 1.

[0033] In an improved embodiment, see Figure 3 As shown, the arc-shaped groove 12 includes a plurality of circular arc-shaped grooves 121 connected in sequence at a set adjustment angle, and the width of the connection between two adjacent circular arc-shaped grooves 121 is equal to the diameter of the boss 13.

[0034] Preferably, the set adjustment angle is 3° to 15°, that is, the angle adjustment range between two adjacent adjusting pieces 1 is 3° to 15°.

[0035] In an improved embodiment, the adjusting piece 1 is an L-shaped adjusting piece, and the connecting hole 11 is located at the corner position of the L-shaped adjusting piece.

[0036] In an improved embodiment, the connecting component includes a bolt 2 and a nut 3. The bolt 2 passes through the connecting holes 11 of each adjusting piece 1 in sequence and is fixed by the nut 3. By screwing and matching the bolt 2 and the nut 3, all the adjusting pieces 1 can be fixed to form an air flow actuator with a curved and swept shape without relative movement. In this improved embodiment, the bolt 2 can be selected as a hexagon bolt or other shaped bolts.

[0037] Taking 10 L-shaped adjusting pieces and 19 circular arc-shaped grooves 121 on each L-shaped adjusting piece, and the aperture of the connecting hole 11 being φ6mm as an example, this specific embodiment illustrates the angle-adjustable air flow actuator of the present invention:

[0038] See Figure 3For the arc-shaped grooves shown in the figure, number the 19 arc-shaped grooves 121 in sequence from one end to the other end, ensuring that the center of the connection hole coincides with the center of the arc-shaped groove 12. Fix 10 L-shaped adjusting pieces with hexagon bolts.

[0039] During the test, set the adjustment angle between two adjacent L-shaped adjusting pieces to 5° (that is, the angle between two adjacent arc-shaped grooves 121 is 5°), and operate as follows:

[0040] First, place the first L-shaped adjusting piece arbitrarily, and align the connection hole 11 of the second L-shaped adjusting piece with the connection hole 11 of the first L-shaped adjusting piece;

[0041] Second, place the boss 13 of the second L-shaped adjusting piece into the arc-shaped groove 121 numbered 9 of the first L-shaped adjusting piece;

[0042] Then, align the connection hole 11 of the third L-shaped adjusting piece with the connection holes 11 of the previous two L-shaped adjusting pieces, and place the boss 13 of the third L-shaped adjusting piece into the arc-shaped groove 121 numbered 8 of the second L-shaped adjusting piece, and so on, until the boss 13 of the tenth L-shaped adjusting piece is placed into the arc-shaped groove 121 numbered 1 of the ninth L-shaped adjusting piece. All the L-shaped adjusting pieces are installed;

[0043] Finally, insert the hexagon bolts into the connection holes 11 that have been aligned in all the L-shaped adjusting pieces, and tighten the nuts 3 to form a rotating blade air flow exciter with a difference of 5°.

[0044] It should be noted here that the number of the above-mentioned adjusting pieces 1 and the adjustment angle between two adjacent adjusting pieces 1 can be adjusted according to actual needs. The protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

[0045] At the same time, the above content is only the preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

[0046] In addition, it should be understood that although this specification is described according to the embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An adjustable-angle airflow exciter for aero-engine blades, characterized in that it is used to simulate the wakes of cambered and swept blades, including: an adjusting vane assembly, the adjusting vane assembly includes a plurality of adjusting vanes (1) with the same structure and stacked in sequence, and an arc-shaped adjusting part is arranged between two adjacent adjusting vanes (1), and the arc-shaped adjusting part is used to adjust the angle between two adjacent adjusting vanes (1); a connecting assembly, the connecting assembly passes through the connecting holes (11) on each adjusting vane (1) to fix the plurality of adjusting vanes (1) to form an airflow exciter for aero-engine blades; wherein, the arc-shaped adjusting part includes: an arc-shaped groove (12), the arc-shaped groove (12) is located on one side of the adjusting vane (1), and the center of the arc-shaped groove (12) coincides with the center of the connecting hole (11); a boss (13), the boss (13) is located on the other side of the adjusting vane (1); when two adjacent adjusting vanes (1) are assembled, the boss (13) of the previous adjusting vane (1) moves in the arc-shaped groove (12) of the next adjusting vane (1), or the boss (13) of the next adjusting vane (1) moves in the arc-shaped groove (12) of the previous adjusting vane (1); the arc-shaped groove (12) includes a plurality of circular arc-shaped grooves (121) connected in sequence according to a set adjusting angle, and the width of the connection part between two adjacent circular arc-shaped grooves (121) is equal to the diameter of the boss (13).

2. The airflow exciter for aero-engine blades according to claim 1, characterized in that: the set adjusting angle is 3° to 15°.

3. The airflow exciter for aero-engine blades according to claim 1, characterized in that: the adjusting vane (1) is an L-shaped adjusting vane, and the connecting hole (11) is located at the corner position of the L-shaped adjusting vane.

4. The airflow exciter for aero-engine blades according to claim 1, characterized in that: the connecting assembly includes a bolt (2) and a nut (3), and the bolt (2) passes through the connecting holes (11) of each adjusting vane (1) in sequence and is fixed by the nut (3).

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