A dynamic response life test design method for aircraft wheel fairings

Abstract

The application belongs to the field of impact dynamics in aircraft design, and particularly relates to a dynamic response life test design method of an aircraft wheel fender. The method comprises the following steps: calculating total test cycles; dividing test stages and determining the test cycles corresponding to each test stage; determining the test cycles corresponding to the land-based use takeoff number and the test cycles corresponding to the ship-based use takeoff number in each test stage; determining the test conditions and test cycles of each test period; determining the test cycles corresponding to the normal air pressure test and the low air pressure test in each test period; and carrying out the dynamic response life test of the wheel fender according to the determined test parameters. The application can examine the stability, installation reliability and other comprehensive performances of the wheel fender structure.

Description

Technical Field

[0001] This application belongs to the field of impact dynamics in aircraft design, and specifically relates to a dynamic response life test design method for aircraft wheel guard plates. Background Technology

[0002] Aircraft wheel well guards mainly consist of side panels, sector components, profiles, supports, and tie rods. Their function is to prevent dust kicked up by the nose wheel from entering the air intake and damaging the engine, thus ensuring the normal operation of the aircraft engine. During takeoff, landing, and taxiing, the nose wheel well guard primarily bears the vibration and aerodynamic loads transmitted from the wheel axle. The overloads experienced by the wheel well guards during takeoff, landing, and taxiing are not damped by the nose landing gear struts, but only by the front tires (tire damping is poor, especially at high altitudes). The stability of the wheel well guard structure is crucial; failure of the guard structure can lead to serious accidents or even aircraft damage. Therefore, it is necessary to conduct dynamic response life tests on the guards to ensure the safety and reliability of the nose landing gear wheel well guard structure throughout the aircraft's lifespan.

[0003] Therefore, it is desirable to have a technical solution to overcome or at least mitigate one of the aforementioned defects of the prior art. Summary of the Invention

[0004] The purpose of this application is to provide a dynamic response life test design method for aircraft wheel guard plates to solve at least one problem existing in the prior art.

[0005] The technical solution of this application is:

[0006] A method for designing a dynamic response life test for aircraft wheel guard plates, comprising:

[0007] Step 1: Determine the life index of the landing gear guard plate based on the life index of the aircraft takeoffs and landings, and calculate the total number of test cycles based on the life index of the landing gear guard plate.

[0008]

[0009] Where η is the reliability coefficient;

[0010] Step 2: Divide the test into phases and determine the number of test cycles for each phase;

[0011] Step 3: Obtain the number of land-based and ship-based takeoffs and landings in the dynamic response life test of the wheel guard plate, and determine the number of test cycles corresponding to the number of land-based and ship-based takeoffs and landings in each test phase.

[0012] Step 4: Divide the number of test cycles corresponding to the number of takeoffs and landings on land-based and the number of test cycles corresponding to the number of takeoffs and landings on ship-based into multiple test cycles, and determine the test conditions and the number of test cycles for each test cycle. The test conditions include sinking speed, maximum sinking speed, weight, and maximum weight.

[0013] Step 5: Determine the ratio of normal pressure test and low pressure test in each test cycle, and calculate the corresponding number of test cycles;

[0014] k cy +k dy =1

[0015] Where, k cy k dy These are the proportionality coefficients for normal pressure tests and low pressure tests, respectively.

[0016] Step 6: Conduct a dynamic response life test on the wheel guard plate based on the test parameters determined in Steps 1 to 5.

[0017] In at least one embodiment of this application, in step four, the test cycle includes four cycles: the test conditions for the first test cycle are the design weight and the design sinking speed; the test conditions for the second test cycle are the maximum weight and the design sinking speed; the test conditions for the third test cycle are the design weight and the maximum sinking speed; and the test conditions for the fourth test cycle are the maximum weight and the maximum sinking speed.

[0018] In at least one embodiment of this application, in step six,

[0019] The wheel guard plate is installed on the landing gear, and the dynamic response life test of the wheel guard plate is achieved by conducting a drop test on the landing gear on a test bench.

[0020] In at least one embodiment of this application, in the dynamic response life test of the wheel guard plate, the test conditions of weight and maximum weight are achieved by the counterweight of the test bench, and the test conditions of sinking speed and maximum sinking speed are achieved by the height of the test bench.

[0021] In at least one embodiment of this application, in the dynamic response life test of the landing gear guard plate, test conditions with different air pressures are achieved by adjusting the pressure of the landing gear tires.

[0022] In at least one embodiment of this application, an acceleration sensor and a strain gauge are installed on the wheel guard plate during the dynamic response life test of the wheel guard plate.

[0023] The invention has at least the following beneficial technical effects:

[0024] The dynamic response life test design method for aircraft wheel guard plates in this application evaluates the comprehensive performance of the wheel guard plate structure, such as stability and installation reliability, through cyclic loading under different sinking speeds and different air pressure conditions, so as to determine the life of the structure. Attached Figure Description

[0025] Figure 1 This is a flowchart of a dynamic response life test design method for an aircraft wheel guard plate according to one embodiment of this application. Detailed Implementation

[0026] 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 some, but not all, 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.

[0027] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this application.

[0028] The following is in conjunction with the appendix Figure 1 This application will be described in further detail.

[0029] This application provides a method for designing dynamic response life tests for aircraft wheel guard plates, including the following steps:

[0030] Step 1: Determine the life index of the landing gear guard plate based on the life index of the aircraft's takeoffs and landings, and calculate the total number of test cycles based on the life index of the landing gear guard plate.

[0031]

[0032] Where η is the reliability coefficient;

[0033] Step 2: Divide the test into phases and determine the number of test cycles for each phase;

[0034] Step 3: Obtain the number of land-based and ship-based takeoffs and landings in the dynamic response life test of the wheel guard plate, and determine the number of test cycles corresponding to the number of land-based and ship-based takeoffs and landings in each test phase.

[0035] Step 4: Divide the number of test cycles corresponding to the number of takeoffs and landings on land-based and the number of test cycles corresponding to the number of takeoffs and landings on ship-based into multiple test cycles, and determine the test conditions and the number of test cycles for each test cycle. The test conditions include sinking speed, maximum sinking speed, weight, and maximum weight.

[0036] Step 5: Determine the ratio of normal pressure test and low pressure test in each test cycle, and calculate the corresponding number of test cycles;

[0037] k cy +k dy =1

[0038] Where, k cy k dy These are the proportionality coefficients for normal pressure tests and low pressure tests, respectively.

[0039] Step 6: Conduct a dynamic response life test on the wheel guard plate based on the test parameters determined in Steps 1 to 5.

[0040] The dynamic response life test design method for aircraft wheel well guards disclosed in this application first determines the life index of the wheel well guards based on the life index of aircraft takeoffs and landings, thereby calculating the total number of test cycles. Then, the test is divided into stages, and the number of test cycles corresponding to each stage is determined. Furthermore, takeoff and landing life is determined separately for conventional land-based use and ship-based use (or equivalent land-based training use), and the corresponding number of test cycles for land-based and ship-based use is determined. Further, the test cycle is determined, dividing each test stage into several test cycles according to land-based and ship-based use. Each test cycle includes tests at low and normal pressure (tire pressure), design sinking speed and maximum sinking speed, and design weight and maximum weight, arranged proportionally. The test cycle should be matched as closely as possible to the maintenance and inspection cycle of field aircraft. The proportion of normal pressure tests and low pressure tests in the life test is determined, and the corresponding number of cycles is calculated. Finally, a test schedule is prepared, and the dynamic response life test scheme for the wheel well guards is determined. The main task is to simulate the operating environment of the wheel well guards under real-world conditions and the loads they bear.

[0041] The dynamic response life test design method for aircraft wheel guard plates disclosed in this application involves installing the wheel guard plates on the landing gear and conducting a drop test on the landing gear using a test bench. The test conditions for weight and maximum weight are achieved by adjusting the counterweights on the test bench, and the test conditions for sinking speed and maximum sinking speed are achieved by adjusting the height of the test bench. Test conditions for different air pressures are achieved by adjusting the pressure of the landing gear tires. An acceleration sensor and strain gauges are installed on the wheel guard plates.

[0042] In a preferred embodiment of this application, the total number of test cycles is calculated to be 20,000. The life test of the dynamic response of the wheel guard plate of a certain type of aircraft is conducted in two stages. In this embodiment, the number of test cycles in both the first and second stages is 10,000. In the first stage, the number of land-based takeoffs and landings is 400 and the number of ship-based takeoffs and landings is 600. Based on the ratio of the land-based takeoff and landing life to the ship-based takeoff and landing life, the number of test cycles corresponding to the number of land-based takeoffs and landings in this stage is 4,000, and the number of test cycles corresponding to the number of ship-based takeoffs and landings is 6,000. In the second stage, the number of land-based takeoffs and landings is 500 and the number of ship-based takeoffs and landings is 500. Based on the ratio of the land-based takeoff and landing life to the ship-based takeoff and landing life, the number of test cycles corresponding to the number of land-based takeoffs and landings in this stage is 5,000, and the number of test cycles corresponding to the number of ship-based takeoffs and landings is 5,000. In this embodiment, 1 takeoff and landing corresponds to 10 test cycles. Furthermore, each usage scenario was divided into four test cycles. The test conditions for the first test cycle were design weight and design sinking speed; the test conditions for the second test cycle were maximum weight and design sinking speed; the test conditions for the third test cycle were design weight and maximum sinking speed; and the test conditions for the fourth test cycle were maximum weight and maximum sinking speed. The number of test cycles corresponding to each test cycle is shown in Table 1. The parameters mentioned in the comprehensive method are summarized as tire pressure, sinking speed, and usage weight.

[0043] Table 1. Number of test cycles for the dynamic response of the wheel guard plate in two stages.

[0044]

[0045] Determine the ratio between normal pressure testing and low pressure testing:

[0046] k cy =0.8, k dy =0.2

[0047] In this embodiment, the specific experimental parameters are shown in Table 2:

[0048] Table 2 Specific test parameters for the dynamic response of the wheel guard plate

[0049]

[0050] The dynamic response life test design method for aircraft wheel well guards disclosed in this application assesses the comprehensive performance of the wheel well guard structure, including stability and installation reliability, under cyclic loading conditions with different descent velocities and air pressures to determine its lifespan. The test stages and cycle divisions for the wheel well guards correspond to actual usage conditions, not only determining the wheel well guard's lifespan but also providing data support for subsequent repair planning. The dynamic response life test of the wheel well guards evaluates the dynamic response under different air pressures, descent velocities, and weights (test weight), fully verifying the stability and reliability of the wheel well guards under various air pressure, descent velocities, and weight environments.

[0051] 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 dynamic response life test design method for aircraft wheel chocks, characterized by, include: Step 1: Determine the life index of the landing gear guard plate based on the life index of the aircraft takeoffs and landings, and calculate the total number of test cycles based on the life index of the landing gear guard plate. Where η is the reliability coefficient; Step 2: Divide the test into phases and determine the number of test cycles for each phase; Step 3: Obtain the number of land-based and ship-based takeoffs and landings in the dynamic response life test of the wheel guard plate, and determine the number of test cycles corresponding to the number of land-based and ship-based takeoffs and landings in each test phase. Step 4: Divide the number of test cycles corresponding to the number of takeoffs and landings on land-based and the number of test cycles corresponding to the number of takeoffs and landings on ship-based into multiple test cycles, and determine the test conditions and the number of test cycles for each test cycle. The test conditions include sinking speed, maximum sinking speed, weight, and maximum weight. Step 5: Determine the ratio of normal pressure test and low pressure test in each test cycle, and calculate the corresponding number of test cycles; k cy +k dy =1 wherein k cy , k dy are the proportional coefficients for normal and low gas pressure tests, respectively. Step 6: Conduct a dynamic response life test on the wheel guard plate based on the test parameters determined in Steps 1 to 5.

2. The dynamic response life test design method of an aircraft wheel chock according to claim 1, characterized in that, In step four, the test cycle includes four cycles. The test conditions for the first test cycle are the design weight and the design sinking speed. The test conditions for the second test cycle are the maximum weight and the design sinking speed. The test conditions for the third test cycle are the design weight and the maximum sinking speed. The test conditions for the fourth test cycle are the maximum weight and the maximum sinking speed.

3. The method for designing dynamic response life test of aircraft wheel guard plates according to claim 1, characterized in that, In step six, The wheel guard plate is installed on the landing gear, and the dynamic response life test of the wheel guard plate is achieved by conducting a drop test on the landing gear on a test bench.

4. The method for designing dynamic response life test of aircraft wheel guard plates according to claim 3, characterized in that, In the dynamic response life test of the wheel guard plate, the test conditions of weight and maximum weight are achieved by the counterweight of the test bench, and the test conditions of sinking speed and maximum sinking speed are achieved by the height of the test bench.

5. The method for designing dynamic response life test of aircraft wheel guard plates according to claim 4, characterized in that, In the dynamic response life test of the landing gear guard plate, test conditions with different air pressures were achieved by adjusting the pressure of the landing gear tires.

6. The method for designing dynamic response life test of aircraft wheel guard plates according to claim 5, characterized in that, In the dynamic response life test of the wheel guard plate, an acceleration sensor and strain gauge were installed on the wheel guard plate.

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