A slat fatigue test support and boundary simulation method

Abstract

The application belongs to the field of aircraft fatigue test design, and particularly relates to a slat fatigue test support and boundary simulation method. The method comprises the following steps: S1, vertically, heading and laterally constraining a fuselage section of a wing-fuselage combination; S2, applying upward vertical load on the right wing box upper surface through counterweight; S3, setting multiple vertical constraint points downward at the front beam of the right wing box, and applying downward vertical constraint load; S4, equivalent the maximum load in the slat load downward working condition to the counterweight load application point of the right wing box; S5, heading constraining the right wing box on the heading flap and aileron support joint of the right wing box, and laterally constraining the right wing box on the joint connected with the landing gear below the right wing box. The application ensures that the wing box deformation is unchanged during the test process, and achieves the purpose of accurate test examination.

Description

Technical Field

[0001] This application belongs to the field of aircraft fatigue test design, and specifically relates to a method for fatigue test support and boundary simulation of slats. Background Technology

[0002] In aircraft structural fatigue strength testing, two factors affect the accuracy of the test: the accurate application of the test load and the realistic simulation of the test support boundary. The accurate application of the test load mainly considers the three elements of force: magnitude, direction, and point of application. The load application point is determined by the test piece structure, the load magnitude is effectively guaranteed by the coordinated loading control system, and the load direction is determined by the application point of the actuator and the load itself. Therefore, ensuring the load direction requires ensuring the accuracy of the relative positions of the application point and the actuator's application point. In slat tests, the application of active loads causes deformation of the wing box along the vertical and yaw directions (spanwise deformation is negligible). This deformation of the wing box causes a change in the relative positions of the slat load application point and the application point of the loading actuator, thus changing the direction of the applied load. Summary of the Invention

[0003] To address the aforementioned technical problems, this application provides a method for fatigue testing support and boundary simulation of slats, which uses multiple constraint devices to maintain the wing in a state of theoretical deformation.

[0004] The slat fatigue test support and boundary simulation method provided in this application mainly includes:

[0005] Step S1: Perform vertical, directional, and lateral constraints on the fuselage section of the wing-body assembly, and adjust the positions of the vertical, directional, and lateral constraint devices to ensure that the measurement points of the right wing box of the wing-body assembly are consistent with the theoretically set positions.

[0006] Step S2: Apply an upward vertical load to the upper surface of the right wing box by means of counterweight, and adjust the magnitude of the vertical load to make the deformation of the right wing box consistent with the deformation under the theoretical load.

[0007] Step S3: Set multiple vertical constraint points Y5-Y16 downward at the front beam of the right wing box. Apply a downward load through the vertical constraint device. The magnitude of the applied load is at least sufficient to prevent the right wing box from deforming upward under the maximum load of the slat fatigue upward working condition connected to the right wing box.

[0008] Step S4: The maximum load under the downward load condition of the slat during the entire test process is equivalent to the counterweight load application point of the right wing box. The counterweight load is adjusted according to the calculated load size so that the right wing box does not deform downward due to the downward load applied by the slat during the fatigue test.

[0009] Step S5: Apply directional constraints to the right wing box at the directional flap and aileron bracket joint of the right wing box, and apply lateral constraints to the right wing box at the joint below the right wing box that connects to the landing gear.

[0010] Preferably, in step S1, the fuselage section is vertically constrained by a vertical constraint device, which includes four devices: two vertical constraint points Y1-Y2 on the front cover of the fuselage section and two vertical constraint points Y3-Y4 on the rear cover of the fuselage section. Each vertical constraint device is fixed to the test bench in the vertical direction.

[0011] Preferably, the vertical constraint device includes two ears, a force sensor, a connecting joint, and a fixed base. The two ears are connected to the test piece connection end of the fuselage section, the other end of the two ears is connected to the force sensor, and the other end of the force sensor is connected to the fixed base through the connecting joint. The fixed base is fixed on the test bench.

[0012] Preferably, in step S1, the fuselage section is oriented under a directional constraint device. The directional constraint device is connected to the directional constraint point X1 on the crossbeam of the fuselage front cover of the fuselage section and extends horizontally before being fixed to the column.

[0013] Preferably, the directional constraint device for directional constraint of the fuselage section's directional constraint point X1 in step S1, the lateral constraint device for lateral constraint of the fuselage section's lateral constraint points Z1-Z2, and the directional constraint device for directional constraint of the right wing box's directional constraint points X2-X3 and the lateral constraint device for lateral constraint of the right wing box's lateral constraint point Z3 in step S5 all include a force sensor and an adjusting screw. One end of the force sensor is connected to the test piece connection end of the fuselage section or the right wing box via a single lug, and the other end of the force sensor is connected to the adjusting screw. The other end of the adjusting screw is connected to a double-lug base set on a column via a single lug, and the column is fixed on the test bench.

[0014] Preferably, in step S3, the second vertical constraint device for vertically constraining vertical constraint points Y5-Y16 includes a first pull plate, a force sensor, a second pull plate, and a tightening screw sleeve. One end of the first pull plate is connected to the test piece connection end of the right wing box via a single / double ear connector. The other end of the first pull plate is connected to the force sensor via a single ear. The other end of the force sensor is connected to the second pull plate via a single ear. The other end of the second pull plate is connected to the tightening screw sleeve. The other end of the tightening screw sleeve is fixed to a fixed base. The fixed base is fixed to the test bench. The magnitude of the downward applied load is adjusted by rotating the tightening screw sleeve.

[0015] This application achieves the purpose of maintaining wing deformation by restricting directional, vertical, and lateral constraints, thereby realistically simulating the effect of support and boundary in slat fatigue testing. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of a preferred embodiment of the slat fatigue test support and boundary simulation method of this application.

[0017] Figure 2 This is a schematic diagram of the vertical constraint device.

[0018] Figure 3 This is a schematic diagram of the second vertical constraint device.

[0019] Figure 4 This is a schematic diagram of the heading and lateral restraint device.

[0020] Among them, 1-Front end cover of fuselage, 2-Rear end cover of fuselage, 3-Fuse section, 4-Right wing box, 5-Test piece connection end, 6-Double ear, 7-Force sensor, 8-Connecting connector, 9-Fixed base, 10-Test piece connection end, 11-Single and double ear connector, 12-First pull plate, 13-Single ear, 14-Force sensor, 15-Single ear, 16-Second pull plate, 17-Tightening screw sleeve, 18-Fixed base, 19-Test piece connection end, 20-Single ear, 21-Force sensor, 22-Adjusting screw, 23-Single ear, 24-Double ear base, 25-Column. Detailed Implementation

[0021] 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 inventive 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.

[0022] This application provides a method for fatigue testing support and boundary simulation of slats, mainly including:

[0023] Step S1: Perform vertical, directional, and lateral constraints on the fuselage section 3 of the wing-body assembly, and adjust the positions of the vertical, directional, and lateral constraint devices to make the measurement points of the right wing box 4 of the wing-body assembly consistent with the theoretically set positions.

[0024] Step S2: Apply an upward vertical load to the upper surface of the right wing box 4 by means of counterweight, and adjust the magnitude of the vertical load so that the deformation of the right wing box 4 is consistent with the deformation under the theoretical load.

[0025] Step S3: Set multiple vertical constraint points Y5-Y16 downward at the front beam of the right wing box 4. Apply a downward load through the vertical constraint device. The magnitude of the applied load is at least sufficient to prevent the right wing box 4 from deforming upward under the maximum load of the slat fatigue upward working condition connected to the right wing box 4.

[0026] Step S4: The maximum load under the downward load condition of the slat during the entire test process is equivalent to the counterweight load application point of the right wing box 4. The counterweight load is adjusted according to the calculated load size so that the right wing box 4 does not deform downward due to the downward load applied by the slat during the fatigue test.

[0027] Step S5: Apply directional constraints to the right wing box 4 at the directional flap and aileron bracket joints, and apply lateral constraints to the right wing box 4 at the joints connecting the right wing box 4 to the landing gear below.

[0028] refer to Figure 1The slat fatigue test uses a wing-body assembly test piece as a support platform. The wing-body assembly includes a front fuselage cover 1, a rear fuselage cover 2, a fuselage section 3, and a right wing box 4. The slat test piece is physically connected and installed on the right wing box. In step S1, the slat is fixed at its placement position and specific height using vertical constraints (Y1-Y4), directional constraints (X1), and lateral constraints (Z1, Z2). By measuring the relative positions, the adjustable devices at each constraint point are adjusted to ensure that the measured values ​​at the right wing box measurement points are consistent with the theoretical positions. Then, in step S2, a vertical load is applied using a counterweight method, and the counterweight weights at each loading point are adjusted. Simultaneously, the wing box deformation is measured to ensure that the deformation after load application is consistent with the deformation under the theoretical load. At this point, the vertical load on the wing box applied using the counterweight method is balanced on the wing-body assembly constraints. Force sensors installed on the wing-body assembly constraint points can monitor the load magnitude at the constraint points (Y1-Y4, X1, Z1-Z2) in real time. In step S3, vertical constraint points (Y5~Y16) are set downward on the front beam of the right wing box. After the constraint is installed, the travel of the loosening and tightening screw sleeve 17 is adjusted, the feedback of the force sensor 14 is monitored, and the displacement of the wing box is measured at the same time to ensure that the wing box is completely fixed and no longer affected by the load during the fatigue test.

[0029] In step S3, the data fed back by the force sensor 14 ensures that the load applied to the right wing box 4 is appropriate and will not damage it. Simultaneously, wing box displacement is measured, primarily to control the wing to achieve its theoretical deformation. This application applies a preload in steps S1-S3 to achieve the theoretical deformation of the wing box. Subsequent steps then constrain the wing in the directional, vertical, and lateral directions to maintain the deformation, thus realistically simulating the support and boundary effects of a slat fatigue test.

[0030] In step S4, the maximum load under the downward load condition of the slat during the entire test process is equivalent to the counterweight load application point of the right wing box section. The counterweight is adjusted according to the calculated load size to ensure that the wing box does not deform downward due to the downward load applied by the slat during the fatigue test.

[0031] It should be noted that in step S3, the vertical constraint load applied by the downwardly set vertical constraint point can ensure that the wing remains fixed when the slat is subjected to the maximum upward load during the fatigue test. In step S4, the magnitude of the counterweight load is increased so that the wing remains fixed when the slat is subjected to the maximum downward load.

[0032] In step S5, directional constraint points (X2, X3) are set on the directional flap and aileron support joint of the right wing box section, and lateral constraint point (Z3) is set on the landing gear and wing connection joint. These constraints, together with the wing's vertical downward constraints (Y5~Y16), form a statically indeterminate constraint system for the right wing box, ensuring that the right wing box does not undergo rigid body displacement or excessive deformation during the fatigue test, thereby ensuring the accuracy of the relative position of the slat load application point, and thus ensuring the accuracy of the slat load application.

[0033] In some optional embodiments, in step S1, the fuselage section 3 is vertically constrained by a vertical constraint device, which includes four devices, two of which are connected to the vertical constraint points Y1-Y2 on the front fuselage cover 1 of the fuselage section 3, and the other two are connected to the vertical constraint points Y3-Y4 on the rear fuselage cover 2 of the fuselage section 3. Each vertical constraint device is fixed to the test bench in the vertical direction.

[0034] In some alternative embodiments, the vertical constraint device includes two ears 6, a force sensor 7, a connecting joint 8, and a fixed base 9. The two ears 6 are connected to the test piece connection end 5 of the fuselage section 3, and the other end of the two ears 6 is connected to the force sensor 7. The other end of the force sensor 7 is connected to the fixed base 9 through the connecting joint 8. The fixed base 9 is fixed on the test bench.

[0035] In some alternative embodiments, in step S1, the fuselage section 3 is oriented under a directional constraint device. The directional constraint device is connected to the directional constraint point X1 on the crossbeam of the fuselage front cover 1 of the fuselage section 3 and extends horizontally before being fixed to the column.

[0036] In some optional embodiments, the directional constraint device for directional constraint point X1 of fuselage section 3 in step S1, the lateral constraint device for lateral constraint points Z1-Z2 of fuselage section 3, and the directional constraint device for directional constraint points X2-X3 of right wing box 4 and the lateral constraint device for lateral constraint point Z3 of right wing box 4 in step S5 all include a force sensor 21 and an adjusting screw 22. One end of the force sensor 21 is connected to the test piece connection end 19 of fuselage section 3 or right wing box 4 through a single ear 20, and the other end of the force sensor 21 is connected to the adjusting screw 22. The other end of the adjusting screw 22 is connected to a double-ear base 24 set on the column 25 through a single ear 23. The column 25 is fixed on the test bench.

[0037] In some optional embodiments, in step S3, the second vertical constraint device for vertically constraining vertical constraint points Y5-Y16 includes a first pull plate 12, a force sensor 14, a second pull plate 16, and a tightening screw sleeve 17. One end of the first pull plate 12 is connected to the test piece connection end 10 of the right wing box 4 through a single-double ear connector 11. The other end of the first pull plate 12 is connected to the force sensor 14 through a single ear 13. The other end of the force sensor 14 is connected to the second pull plate 16 through a single ear 15. The other end of the second pull plate 16 is connected to the tightening screw sleeve 17. The other end of the tightening screw sleeve 17 is fixed on a fixed base 18. The fixed base 18 is fixed on the test bench. The magnitude of the downward applied load is adjusted by rotating the tightening screw sleeve 17.

[0038] Compared with the prior art, the advantages or positive effects of this application include:

[0039] 1) Compared with the previous simulation of slat support boundary through certain working condition loads, the simulation of slat support boundary determined by deformation is more accurate.

[0040] 2) The statically indeterminate constraint of the right wing box section effectively limited the slat connection boundary, ensuring that the deformation and displacement at the support boundary did not change due to the application of slat fatigue load during the test.

[0041] 3) A statically indeterminate fully constrained system was set up on the wing-body combination test support platform, which can effectively prevent the right wing box section from failing to constrain or overload caused by test accidents during the test, and ensure the accurate position of the right wing box section.

[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 method for fatigue testing support and boundary simulation of slats, characterized in that, include: Step S1: Perform vertical, directional and lateral constraints on the fuselage section (3) of the wing-body assembly, and adjust the position of the vertical, directional and lateral constraint devices to make the measurement points of the right wing box (4) of the wing-body assembly consistent with the theoretical set position. Step S2: Apply an upward vertical load to the upper surface of the right wing box (4) in the form of counterweight, and adjust the size of the vertical load so that the deformation of the right wing box (4) is consistent with the deformation under the theoretical load. Step S3: Set multiple vertical constraint points Y5-Y16 downward at the front beam of the right wing box (4), and apply a downward load through the vertical constraint device. The magnitude of the applied load is at least enough to prevent the right wing box (4) from deforming upward under the maximum load of the slat fatigue upward working condition connected to the right wing box (4). Step S4: The maximum load under the downward load condition of the slat load during the entire test process is equivalent to the counterweight load application point of the right wing box (4). The counterweight load is adjusted according to the calculated load size so that the right wing box (4) does not deform downward due to the downward load applied by the slat during the fatigue test. Step S5: Apply directional constraints to the right wing box (4) at the directional flap and aileron bracket joints of the right wing box (4), and apply lateral constraints to the right wing box (4) at the joints connecting the right wing box (4) to the landing gear below the right wing box (4).

2. The slat fatigue test support and boundary simulation method as described in claim 1, characterized in that, In step S1, the fuselage section (3) is vertically constrained by a vertical constraint device. The vertical constraint device includes four devices, two of which are vertical constraint points Y1-Y2 on the front fuselage cover (1) of the fuselage section (3), and the other two are vertical constraint points Y3-Y4 on the rear fuselage cover (2) of the fuselage section (3). Each vertical constraint device is fixed to the test bench in the vertical direction.

3. The slat fatigue test support and boundary simulation method as described in claim 2, characterized in that, The vertical constraint device includes two ears (6), a force sensor (7), a connecting joint (8), and a fixed base (9). The two ears (6) are connected to the test piece connection end (5) of the fuselage section (3). The other end of the two ears (6) is connected to the force sensor (7). The other end of the force sensor (7) is connected to the fixed base (9) through the connecting joint (8). The fixed base (9) is fixed on the test bench.

4. The slat fatigue test support and boundary simulation method as described in claim 1, characterized in that, In step S1, the fuselage section (3) is oriented under a directional constraint device. The directional constraint device is connected to the directional constraint point X1 on the crossbeam of the fuselage front cover (1) of the fuselage section (3), and is fixed on the column after extending horizontally.

5. The slat fatigue test support and boundary simulation method as described in claim 4, characterized in that, The heading constraint device for heading constraint point X1 of fuselage section (3) in step S1, the lateral constraint device for lateral constraint points Z1-Z2 of fuselage section (3), and the heading constraint device for heading constraint points X2-X3 of right wing box (4) in step S5, as well as the lateral constraint device for lateral constraint point Z3 of right wing box (4), all include a force sensor (21) and an adjusting screw (22). One end of the force sensor (21) is connected to the test piece connection end (19) of fuselage section (3) or right wing box (4) through a single ear (20), and the other end of the force sensor (21) is connected to the adjusting screw (22). The other end of the adjusting screw (22) is connected to a double-ear base (24) set on the column (25) through a single ear (23). The column (25) is fixed on the test bench.

6. The slat fatigue test support and boundary simulation method as described in claim 1, characterized in that, In step S3, the second vertical constraint device for vertically constraining vertical constraint points Y5-Y16 includes a first pull plate (12), a force sensor (14), a second pull plate (16), and a tightening screw sleeve (17). One end of the first pull plate (12) is connected to the test piece connection end (10) of the right wing box (4) through a single-double ear connector (11). The other end of the first pull plate (12) is connected to the force sensor (14) through a single ear (13). The other end of the force sensor (14) is connected to the second pull plate (16) through a single ear (15). The other end of the second pull plate (16) is connected to the tightening screw sleeve (17). The other end of the tightening screw sleeve (17) is fixed on the fixed base (18). The fixed base (18) is fixed on the test bench. The magnitude of the downward applied load is adjusted by rotating the tightening screw sleeve (17).

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