Method and device for evaluating consistency of ground test and flight test of airplane

Abstract

The invention belongs to the technical field of aircraft test data processing, and relates to an aircraft ground test and flight test consistency evaluation method and device. The method comprises the following steps: acquiring strain data of each first measuring point of a ground test, and acquiring strain data of each second measuring point of a flight test; fusing the finite element simulation data with the strain data of each first measuring point of the ground test, calculating the strain data of each second measuring point, reconstructing a ground test strain field containing the strain data of each first measuring point and each second measuring point, and fusing the finite element simulation data with the strain data of each second measuring point of the flight test to obtain a ground test strain field containing the strain data of each first measuring point and each second measuring point. Calculating strain data of each first measuring point, and reconstructing a flight test strain field containing the strain data of each first measuring point and each second measuring point; and for the reconstructed ground test strain field and the flight test strain field, counting the proportion of the test points of which the strain data difference value of the same test point is smaller than a set value, and taking the proportion as a consistency index of the ground test and the flight test. The utilization rate of test data is improved.

Description

Technical Field

[0001] The present application belongs to the technical field of aircraft test data processing, and in particular relates to a method and device for evaluating the consistency between aircraft ground tests and flight tests. Background Art

[0002] Full-scale aircraft ground testing is a key step before an aircraft flight test and an important guarantee for flight test safety. Ground testing is an equivalent simulation of the load conditions of an aircraft during actual flight. The accuracy and reliability of load simulation are of great guiding significance for the implementation of flight tests. Usually, ground tests and flight tests use aircraft of the same model but different sorties. The number and distribution of strain measurement points in the two tests are very different, making it difficult to conduct air-ground test consistency evaluation on these two discrete, heterogeneous measurement data.

[0003] At present, after a successful flight test, the first thing to do is to conduct a comprehensive inspection of the test aircraft, and judge the safety of the structural design based on the inspection results. Then, the consistency of the air-ground test is roughly assessed by comparing the strain distribution trends of the same key parts in the ground test and the flight test. The current problem is that there is a lack of consistency assessment methods and tools for two types of heterogeneous data. It is also very cumbersome to query the test strain values ​​and strain distribution states in the later stage. These test data are of little help to the update of aircraft structure design. Summary of the invention

[0004] In order to solve the above problems, the present application provides a method and device for evaluating the consistency of aircraft ground tests and flight tests. By fusing the strain data of virtual simulation with the strain data of ground tests and flight tests, the strain field of each test is reconstructed, thereby intuitively expressing the loading state of the structure in the two tests, and then performing consistency and correlation analysis on the strains at the same position, and accurately verifying whether the air-ground tests are consistent based on the analysis results.

[0005] The first aspect of the present application provides a method for evaluating the consistency between aircraft ground tests and flight tests, mainly comprising: Step S1, obtaining strain data of each first measuring point of the ground test, and obtaining strain data of each second measuring point of the flight test; Step S2, fusing the finite element simulation data with the strain data of each first measuring point of the ground test, calculating the strain data of each second measuring point, and reconstructing the ground test strain field including the strain data of each first measuring point and each second measuring point. Similarly, fusing the finite element simulation data with the strain data of each second measuring point of the flight test, calculating the strain data of each first measuring point, and reconstructing the flight test strain field including the strain data of each first measuring point and each second measuring point. Step S3: for the reconstructed ground test strain field and flight test strain field, the proportion of measuring points whose strain data difference of the same measuring point is less than the set value is counted as the consistency index between the ground test and the flight test.

[0006] Preferably, step S1 further comprises: The abnormal values ​​in the strain data of each first measuring point of the ground test are eliminated, and the abnormal values ​​in the strain data of each second measuring point of the flight test are eliminated.

[0007] Preferably, step S2 further comprises: Step S21, extracting strain data of node units in a specified range near each second measuring point in the finite element simulation data, and jointly forming a sample space centered on the second measuring point with the strain data of multiple first measuring points in the ground test, and calculating the strain data of the second measuring point in the sample space using an adaptively modified Kriging interpolation method; Step S22: extracting strain data of node units in a specified range near each first measuring point in the finite element simulation data, and jointly forming a sample space centered on the first measuring point with the strain data of multiple second measuring points of the flight test, and calculating the strain data of the first measuring point in the sample space using an adaptively modified Kriging interpolation method.

[0008] Preferably, the strain data of the node units within the specified range are gradually searched through a preset search radius and a search increment, and the search radius and the search increment are both set to the average scale of the units during finite element simulation modeling.

[0009] Preferably, in step S3, the set value is 5%.

[0010] The second aspect of the present application provides an aircraft ground test and flight test consistency assessment device, which mainly includes: A test data acquisition module, used to acquire strain data of each first measuring point of a ground test and to acquire strain data of each second measuring point of a flight test; The test strain field reconstruction module is used to fuse the finite element simulation data with the strain data of each first measuring point of the ground test, calculate the strain data of each second measuring point, and reconstruct the ground test strain field including the strain data of each first measuring point and each second measuring point. Similarly, the finite element simulation data is fused with the strain data of each second measuring point of the flight test, calculate the strain data of each first measuring point, and reconstruct the flight test strain field including the strain data of each first measuring point and each second measuring point. The consistency evaluation module is used to count the proportion of measuring points whose strain data difference of the same measuring point is less than the set value for the reconstructed ground test strain field and flight test strain field, as a consistency indicator between the ground test and the flight test.

[0011] Preferably, the test data acquisition module includes: The outlier elimination unit is used to eliminate outliers in the strain data of each first measuring point in the ground test and to eliminate outliers in the strain data of each second measuring point in the flight test.

[0012] Preferably, the test strain field reconstruction module comprises: A second measuring point strain data calculation unit is used to extract the strain data of the node units in a specified range near the position of each second measuring point in the finite element simulation data, and together with the strain data of multiple first measuring points of the ground test, form a sample space centered on the second measuring point, and in the sample space, use an adaptive modified Kriging interpolation method to calculate the strain data of the second measuring point; The first measuring point strain data calculation unit is used to extract the strain data of the node units in a specified range near the position of each first measuring point in the finite element simulation data, and together with the strain data of multiple second measuring points of the flight test, form a sample space centered on the first measuring point. In the sample space, the strain data of the first measuring point is calculated using the adaptively modified Kriging interpolation method.

[0013] Preferably, the strain data of the node units within the specified range are gradually searched through a preset search radius and a search increment, and the search radius and the search increment are both set to the average scale of the units during finite element simulation modeling.

[0014] Preferably, the set value is 5%.

[0015] This application improves the accuracy and reliability of air-to-ground test consistency assessment, increases the utilization rate of test data, and can more effectively support aircraft structural design and modification. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a flow chart of a preferred embodiment of the method for evaluating the consistency between aircraft ground tests and flight tests of the present application. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical scheme and advantages of the implementation of this application clearer, the technical scheme in the implementation of this application will be described in more detail in combination with the drawings in the implementation of this application. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The described implementation is a part of the implementation of this application, not all of the implementations. The implementation described below with reference to the drawings is exemplary and is intended to be used to explain this application, and cannot be understood as a limitation on this application. Based on the implementation in this application, all other implementations obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The implementation of this application is described in detail below in combination with the drawings.

[0018] The first aspect of the present application provides a method for evaluating the consistency between aircraft ground tests and flight tests, such as Figure 1 As shown, it mainly includes: Step S1, obtaining strain data of each first measuring point of the ground test, and obtaining strain data of each second measuring point of the flight test; Step S2, fusing the finite element simulation data with the strain data of each first measuring point of the ground test, calculating the strain data of each second measuring point, and reconstructing the ground test strain field including the strain data of each first measuring point and each second measuring point. Similarly, fusing the finite element simulation data with the strain data of each second measuring point of the flight test, calculating the strain data of each first measuring point, and reconstructing the flight test strain field including the strain data of each first measuring point and each second measuring point. Step S3: for the reconstructed ground test strain field and flight test strain field, the proportion of measuring points whose strain data difference of the same measuring point is less than the set value is counted as the consistency index between the ground test and the flight test.

[0019] In step S1, the present application extracts strain data of two tests for the key evaluation area of ​​the aircraft structure. As mentioned above, the strain gauges of the two tests are pasted at different positions. The first measuring point and the second measuring point are used here to distinguish them. The measuring points of the ground test are collectively referred to as the first measuring point, and the measuring points of the flight test are collectively referred to as the second measuring point.

[0020] In some optional implementations, step S1 further includes: The abnormal values ​​in the strain data of each first measuring point of the ground test are eliminated, and the abnormal values ​​in the strain data of each second measuring point of the flight test are eliminated.

[0021] In this embodiment, the validity of the strain data of the flight test and the ground test is judged. The validity judgment of the test data is mainly used to eliminate the strain gauges that cannot truly reflect the stress state of the structure in the ground test and the flight test, that is, abnormal gauges. The abnormal gauges are identified by abnormal values. The abnormal values ​​mainly include the following four categories: the strain value is too large, for example, greater than 20000με; the strain value is too small, for example, less than -20000με; the continuous acquisition step data oscillates, which is judged by linearity; in a single load increment step, the strain change exceeds the threshold, for example, exceeds 5000με.

[0022] Then, in step S2, the test strain field is reconstructed. The principle is to use the strain data of the virtual simulation to fill the strain data of the flight test and the strain data of the ground test, so that the flight test and the ground test have the same measuring points.

[0023] In some optional implementations, step S2 further includes: Step S21, extracting strain data of node units in a specified range near each second measuring point in the finite element simulation data, and jointly forming a sample space centered on the second measuring point with the strain data of multiple first measuring points in the ground test, and calculating the strain data of the second measuring point in the sample space using an adaptively modified Kriging interpolation method; Step S22: extracting strain data of node units in a specified range near each first measuring point in the finite element simulation data, and jointly forming a sample space centered on the first measuring point with the strain data of multiple second measuring points of the flight test, and calculating the strain data of the first measuring point in the sample space using an adaptively modified Kriging interpolation method.

[0024] In this embodiment, the principles of step S21 and step S22 are the same. Taking step S21 as an example for explanation, the ground test itself has strain data of the first measuring point, and the strain data of the second measuring point needs to be filled. For this purpose, the data is first screened in the simulation data. It can be understood that the second measuring point is a specific point, and the simulation data obtains the strain data of the unit node. The strain data of the unit node cannot be directly equivalent to the strain data of a specific point. Therefore, here, the second measuring point is used as a reference as the specific point, and the strain data of one or more finite element simulation nodes are obtained within a specified range (the strain data of the finite element simulation node is called virtual data), and then the strain data of multiple first measuring points around the second measuring point are fused (here is the measured data of the ground test itself). The specific fusion process is to construct a sample space, and then use the adaptive modified Kriging interpolation method to calculate the strain data of the second measuring point. During the interpolation process, the weight α of the virtual data is increased. 仿真 And the weight α of the measured data 试验 : α 仿真=N 仿真 / (N 试验 *(N 试验 +N 仿真 )); α 试验 =1-α 仿真 .

[0025] Among them, N 仿真 is the number of measurement points of virtual data in the sample space, N 试验 is the number of measurement points of the measured data in the sample space.

[0026] In some optional implementations, the strain data of the node units within the specified range are gradually searched through a preset search radius and a search increment, and the search radius and the search increment are both set to the average scale of the units during finite element simulation modeling.

[0027] In this embodiment, the screening of simulation data needs to be based on the coordinates of the strain measurement points of the flight test and the ground static test. By presetting the search radius R (the default is the average unit scale, specified during modeling), a circular search is performed in the plane to find the node units near the ground test and flight test measurement points, and the simulation analysis strain data with the same measurement direction as the corresponding test is extracted. In the process of cyclically expanding the search radius R, the single search increment is 1 average unit scale value, and the cyclic search will stop when the range covers all the node units in the specified range.

[0028] By reconstructing two ground test strain fields and flight test strain fields that can be measured in one-to-one correspondence in the above manner, the consistency of the flight test data and the ground test data can be calculated in step S4.

[0029] In some optional implementations, in step S3, the set value is 5%.

[0030] In this embodiment, a consistency coefficient calculation method based on probability statistics is adopted, and the proportion of measurement points φ whose strain data (real measurement points + strain data of virtual measurement points) of ground tests and flight tests in the evaluation area is less than 5% is calculated as the basis for consistency evaluation of air-to-ground tests.

[0031] In addition, the correlation of strain field distribution state can also be determined: the correlation of strain field distribution is mainly determined by the covariance of spatial strain data of ground test and flight test samples after expansion, and the calculation expression is: , is the mean square error of spatial strain data of ground test and flight test samples, , is the strain of the i-th measurement point in the ground test, is the strain of the ith measurement point in the flight test, is the correlation coefficient, m is the number of measurement points in the sample space, and pi is 2.

[0032] The consistency assessment method provided in this application can not only intuitively display the distribution state of the structural strain field in the aircraft ground test and flight test, but also quantitatively give the correlation and consistency assessment results of the two test data, replacing the traditional rough judgment method based on the approximate distribution and trend of the data, and greatly improving the accuracy and reliability of consistency assessment of air-to-ground tests.

[0033] The second aspect of the present application provides an aircraft ground test and flight test consistency assessment device corresponding to the above method, mainly comprising: A test data acquisition module, used to acquire strain data of each first measuring point of a ground test and to acquire strain data of each second measuring point of a flight test; The test strain field reconstruction module is used to fuse the finite element simulation data with the strain data of each first measuring point of the ground test, calculate the strain data of each second measuring point, and reconstruct the ground test strain field including the strain data of each first measuring point and each second measuring point. Similarly, the finite element simulation data is fused with the strain data of each second measuring point of the flight test, calculate the strain data of each first measuring point, and reconstruct the flight test strain field including the strain data of each first measuring point and each second measuring point. The consistency evaluation module is used to count the proportion of measuring points whose strain data difference of the same measuring point is less than the set value for the reconstructed ground test strain field and flight test strain field, as a consistency indicator between the ground test and the flight test.

[0034] In some optional implementations, the test data acquisition module includes: The outlier elimination unit is used to eliminate outliers in the strain data of each first measuring point in the ground test and to eliminate outliers in the strain data of each second measuring point in the flight test.

[0035] In some optional embodiments, the test strain field reconstruction module includes: A second measuring point strain data calculation unit is used to extract the strain data of the node units in a specified range near the position of each second measuring point in the finite element simulation data, and together with the strain data of multiple first measuring points of the ground test, form a sample space centered on the second measuring point, and in the sample space, use an adaptive modified Kriging interpolation method to calculate the strain data of the second measuring point; The first measuring point strain data calculation unit is used to extract the strain data of the node units in a specified range near the position of each first measuring point in the finite element simulation data, and together with the strain data of multiple second measuring points of the flight test, form a sample space centered on the first measuring point. In the sample space, the strain data of the first measuring point is calculated using the adaptively modified Kriging interpolation method.

[0036] In some optional implementations, the strain data of the node units within the specified range are gradually searched through a preset search radius and a search increment, and the search radius and the search increment are both set to the average scale of the units during finite element simulation modeling.

[0037] In some optional implementations, the set value is 5%.

[0038] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for evaluating the consistency between aircraft ground test and flight test, characterized in that: include: Step S1, obtaining strain data of each first measuring point of the ground test, and obtaining strain data of each second measuring point of the flight test; Step S2, fusing the finite element simulation data with the strain data of each first measuring point of the ground test, calculating the strain data of each second measuring point, and reconstructing the ground test strain field including the strain data of each first measuring point and each second measuring point. Similarly, fusing the finite element simulation data with the strain data of each second measuring point of the flight test, calculating the strain data of each first measuring point, and reconstructing the flight test strain field including the strain data of each first measuring point and each second measuring point. Step S3: for the reconstructed ground test strain field and flight test strain field, the proportion of measuring points whose strain data difference of the same measuring point is less than the set value is counted as the consistency index between the ground test and the flight test.

2. The method for evaluating the consistency between aircraft ground test and flight test according to claim 1, characterized in that: Step S1 further comprises: The abnormal values ​​in the strain data of each first measuring point of the ground test are eliminated, and the abnormal values ​​in the strain data of each second measuring point of the flight test are eliminated.

3. The method for evaluating the consistency between aircraft ground test and flight test according to claim 1, characterized in that: Step S2 further comprises: Step S21, extracting strain data of node units in a specified range near each second measuring point in the finite element simulation data, and jointly forming a sample space centered on the second measuring point with the strain data of multiple first measuring points in the ground test, and calculating the strain data of the second measuring point in the sample space using an adaptively modified Kriging interpolation method; Step S22: extracting strain data of node units in a specified range near each first measuring point in the finite element simulation data, and jointly forming a sample space centered on the first measuring point with the strain data of multiple second measuring points of the flight test, and calculating the strain data of the first measuring point in the sample space using an adaptively modified Kriging interpolation method.

4. The method for evaluating the consistency between aircraft ground test and flight test according to claim 3, characterized in that: The strain data of the node units within the specified range are gradually searched through a preset search radius and a search increment, wherein the search radius and the search increment are both set to the average unit scale during finite element simulation modeling.

5. The method for evaluating the consistency between aircraft ground test and flight test according to claim 1, characterized in that: In step S3, the setting value is 5%.

6. An aircraft ground test and flight test consistency assessment device, characterized in that: include: A test data acquisition module, used to acquire strain data of each first measuring point of a ground test and to acquire strain data of each second measuring point of a flight test; The test strain field reconstruction module is used to fuse the finite element simulation data with the strain data of each first measuring point of the ground test, calculate the strain data of each second measuring point, and reconstruct the ground test strain field including the strain data of each first measuring point and each second measuring point. Similarly, the finite element simulation data is fused with the strain data of each second measuring point of the flight test, calculate the strain data of each first measuring point, and reconstruct the flight test strain field including the strain data of each first measuring point and each second measuring point. The consistency evaluation module is used to count the proportion of measuring points whose strain data difference of the same measuring point is less than the set value for the reconstructed ground test strain field and flight test strain field, as a consistency indicator between the ground test and the flight test.

7. The aircraft ground test and flight test consistency assessment device according to claim 6, characterized in that: The test data acquisition module comprises: The outlier elimination unit is used to eliminate outliers in the strain data of each first measuring point in the ground test and to eliminate outliers in the strain data of each second measuring point in the flight test.

8. The aircraft ground test and flight test consistency assessment device according to claim 6, characterized in that: The test strain field reconstruction module includes: A second measuring point strain data calculation unit is used to extract the strain data of the node units in a specified range near the position of each second measuring point in the finite element simulation data, and together with the strain data of multiple first measuring points of the ground test, form a sample space centered on the second measuring point, and in the sample space, use an adaptive modified Kriging interpolation method to calculate the strain data of the second measuring point; The first measuring point strain data calculation unit is used to extract the strain data of the node units in a specified range near the position of each first measuring point in the finite element simulation data, and together with the strain data of multiple second measuring points of the flight test, form a sample space centered on the first measuring point. In the sample space, the strain data of the first measuring point is calculated using the adaptively modified Kriging interpolation method.

9. The aircraft ground test and flight test consistency assessment device according to claim 8, characterized in that: The strain data of the node units within the specified range are gradually searched through a preset search radius and a search increment, wherein the search radius and the search increment are both set to the average unit scale during finite element simulation modeling.

10. The aircraft ground test and flight test consistency assessment device according to claim 6, characterized in that: The set value is 5%.

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