An aircraft ground test and flight test consistency evaluation method and device

Abstract

This application belongs to the technical field of aircraft test data processing, and relates to a method and device for evaluating the consistency between aircraft ground tests and flight tests. The method includes: obtaining the strain data of each first measurement point in the ground test, and obtaining the strain data of each second measurement point in the flight test; fusing the finite element simulation data with the strain data of each first measurement point in the ground test, calculating the strain data of each second measurement point, reconstructing the ground test strain field including the strain data of each first measurement point and each second measurement point, fusing the finite element simulation data with the strain data of each second measurement point in the flight test, calculating the strain data of each first measurement point, and reconstructing the flight test strain field including the strain data of each first measurement point and each second measurement point; for the reconstructed ground test strain field and flight test strain field, counting the proportion of measurement points with the difference in strain data of the same measurement point less than the set value as the consistency index between the ground test and the flight test. This application improves the utilization rate of test data.

Description

Technical Field

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

[0002] Full-scale aircraft ground tests are a crucial link before aircraft flight tests and an important guarantee for flight test safety. Ground tests are an equivalent simulation of the loading conditions during the actual flight of the aircraft. The accuracy and reliability of load simulation have important guiding significance for the implementation of flight tests. Usually, different aircraft of the same model are used in ground tests and flight tests, and the differences in the number and distribution of strain measurement points in the two tests are very large, making it difficult to evaluate the consistency of ground-air tests for these two types of discrete, heterogeneous, and isomeric measurement data.

[0003] Currently, after a flight test is successful, a comprehensive inspection of the test flight aircraft is first required, and the safety of the structural design is judged based on the inspection results. Then, the consistency of ground-air tests is roughly evaluated by comparing whether the strain distribution trends at the same key assessment parts in ground tests and flight tests are consistent. Currently, there is a lack of means and tools for evaluating the consistency of two types of homogeneous and isomeric data. Later, it is also very cumbersome to query test strain values and strain distribution states, and these test data are less helpful for the update of aircraft structural design. Summary of the Invention

[0004] To solve the above problems, this application provides a method and device for evaluating the consistency between 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 fields of each test are reconstructed, so as to intuitively express the load-bearing states of the structure in the two tests. Then, the consistency and correlation of the strains at the same positions are analyzed, and whether the ground-air tests are consistent is accurately verified based on the analysis results.

[0005] The first aspect of this application provides a method for evaluating the consistency between aircraft ground tests and flight tests, mainly including:

[0006] Step S1: Obtain the strain data of each first measurement point in the ground test and the strain data of each second measurement point in the flight test;

[0007] Step S2: Fuse the finite element simulation data with the strain data of each first measurement point in the ground test, calculate the strain data of each second measurement point, and reconstruct the ground test strain field including the strain data of each first measurement point and each second measurement point. Similarly, fuse the finite element simulation data with the strain data of each second measurement point in the flight test, calculate the strain data of each first measurement point, and reconstruct the flight test strain field including the strain data of each first measurement point and each second measurement point;

[0008] Step S3: For the reconstructed ground test strain field and the flight test strain field, count the proportion of measurement points where the strain data difference at the same measurement points is less than the set value, and use it as the consistency index between the ground test and the flight test.

[0009] Preferably, step S1 further includes:

[0010] Eliminate the outliers in the strain data of each first measurement point in the ground test, and eliminate the outliers in the strain data of each second measurement point in the flight test.

[0011] Preferably, step S2 further includes:

[0012] Step S21: Extract the strain data of the node elements in a specified range near the positions of each second measurement point from the finite element simulation data, and jointly form a sample space centered on the second measurement point with the strain data of multiple first measurement points in the ground test. In this sample space, use the adaptively corrected Kriging interpolation method to calculate the strain data of the second measurement point;

[0013] Step S22: Extract the strain data of the node elements in a specified range near the positions of each first measurement point from the finite element simulation data, and jointly form a sample space centered on the first measurement point with the strain data of multiple second measurement points in the flight test. In this sample space, use the adaptively corrected Kriging interpolation method to calculate the strain data of the first measurement point.

[0014] Preferably, gradually search for the strain data of the node elements in the specified range through a preset search radius and search increment, and both the search radius and the search increment are set to the average element scale during finite element simulation modeling.

[0015] Preferably, in step S3, the set value is 5%.

[0016] The second aspect of this application provides a device for evaluating the consistency between aircraft ground tests and flight tests, mainly including:

[0017] A test data acquisition module, used to acquire the strain data of each first measurement point in the ground test and acquire the strain data of each second measurement point in the flight test;

[0018] A test strain field reconstruction module, used to fuse the finite element simulation data with the strain data of each first measurement point in the ground test, calculate the strain data of each second measurement point, and reconstruct the ground test strain field including the strain data of each first measurement point and each second measurement point. Similarly, fuse the finite element simulation data with the strain data of each second measurement point in the flight test, calculate the strain data of each first measurement point, and reconstruct the flight test strain field including the strain data of each first measurement point and each second measurement point;

[0019] The consistency evaluation module is used to count the proportion of measurement points with the difference in strain data at the same measurement points between the reconstructed ground test strain field and the flight test strain field being less than the set value, and use it as the consistency index between the ground test and the flight test.

[0020] Preferably, the test data acquisition module includes:

[0021] The outlier rejection unit is used to reject outliers in the strain data of each first measurement point in the ground test and outliers in the strain data of each second measurement point in the flight test.

[0022] Preferably, the test strain field reconstruction module includes:

[0023] The second measurement point strain data calculation unit is used to extract the strain data of the node elements within a specified range near the position of each second measurement point from the finite element simulation data, and jointly form a sample space centered on the second measurement point with the strain data of multiple first measurement points in the ground test. In the sample space, the adaptive modified Kriging interpolation method is used to calculate the strain data of the second measurement point;

[0024] The first measurement point strain data calculation unit is used to extract the strain data of the node elements within a specified range near the position of each first measurement point from the finite element simulation data, and jointly form a sample space centered on the first measurement point with the strain data of multiple second measurement points in the flight test. In the sample space, the adaptive modified Kriging interpolation method is used to calculate the strain data of the first measurement point.

[0025] Preferably, the strain data of the node elements within the specified range are gradually searched through a preset search radius and search increment, and both the search radius and the search increment are set to the average element scale during finite element simulation modeling.

[0026] Preferably, the set value is 5%.

[0027] This application improves the accuracy and reliability of the ground-air test consistency evaluation, improves the utilization rate of test data, and can more effectively support aircraft structure design and modification. Description of the Drawings

[0028] Figure 1 It is a flowchart of a preferred embodiment of the method for evaluating the consistency between the aircraft ground test and the flight test of this application. Detailed Embodiments

[0029] To make the purpose, technical solution and advantages of the present application clearer, the technical solution in the embodiments of the present application will be described in more detail below in conjunction with the accompanying drawings in the embodiments of the present application. In the drawings, the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The described embodiments are part of the embodiments of the present application, rather than all of the embodiments. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present application, and should not be construed as a limitation to the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application. The embodiments of the present application will be described in detail below in conjunction with the accompanying drawings.

[0030] In the first aspect of the present application, a method for evaluating the consistency between aircraft ground tests and flight tests is provided. As Figure 1 shown, it mainly includes:

[0031] Step S1: Obtain the strain data of each first measurement point in the ground test, and obtain the strain data of each second measurement point in the flight test;

[0032] Step S2: Integrate the finite element simulation data with the strain data of each first measurement point in the ground test, calculate the strain data of each second measurement point, and reconstruct the ground test strain field including the strain data of each first measurement point and each second measurement point. Similarly, integrate the finite element simulation data with the strain data of each second measurement point in the flight test, calculate the strain data of each first measurement point, and reconstruct the flight test strain field including the strain data of each first measurement point and each second measurement point;

[0033] Step S3: For the reconstructed ground test strain field and flight test strain field, count the proportion of measurement points where the difference in strain data of the same measurement point is less than the set value, and use it as the consistency index between the ground test and the flight test.

[0034] In step S1 of the present application, for the key evaluation area of the aircraft structure, the strain data of the two tests are extracted. As mentioned above, the paste positions of the strain gauges in the two tests are different. Here, the first measurement point and the second measurement point are used for distinction. Each measurement point in the ground test is collectively referred to as the first measurement point, and each measurement point in the flight test is collectively referred to as the second measurement point.

[0035] In some alternative embodiments, step S1 further includes:

[0036] Eliminate the outliers in the strain data of each first measurement point in the ground test, and eliminate the outliers in the strain data of each second measurement point in the flight test.

[0037] In this embodiment, the effectiveness of the strain data from flight tests and ground tests is determined. The determination of the effectiveness of test data is mainly used to eliminate the strain gauges that cannot truly reflect the stress state of the structure in ground tests and flight tests, that is, abnormal gauges. Abnormal gauges are identified through abnormal values, and the abnormal values mainly include the following four categories: the strain value is too large, for example, greater than 20,000 με; the strain value is too small, for example, less than -20,000 με; the data of consecutive acquisition steps show oscillations, which is determined by linearity; in a single load increment step, the strain change exceeds the threshold, for example, exceeds 5,000 με.

[0038] After that, in step S2, the test strain field is reconstructed. The principle is to use the strain data of virtual simulation to fill the strain data of flight tests and ground tests, so that the flight tests and ground tests have the same measuring points.

[0039] In some alternative embodiments, step S2 further includes:

[0040] Step S21: Extract the strain data of the node elements within a specified range near the positions of each second measuring point from the finite element simulation data, and jointly form a sample space centered on the second measuring point with the strain data of multiple first measuring points in the ground test. In the sample space, the strain data of the second measuring point is calculated using the adaptive modified Kriging interpolation method;

[0041] Step S22: Extract the strain data of the node elements within a specified range near the positions of each first measuring point from the finite element simulation data, and jointly form a sample space centered on the first measuring point with the strain data of multiple second measuring points in the flight test. In the sample space, the strain data of the first measuring point is calculated using the adaptive modified Kriging interpolation method.

[0042] In this embodiment, the principles of step S21 and step S22 are the same. Taking step S21 as an example for illustration, the ground test itself has the strain data of the first measuring point, and the strain data of the second measuring point needs to be filled. For this purpose, first, data is 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 unit nodes. The strain data of unit nodes cannot be directly equivalent to the strain data of a specific point. Therefore, here, taking the specific point of the second measuring point as a reference, the strain data of one or more finite element simulation nodes (the strain data of finite element simulation nodes is called virtual data) is obtained within the specified range, and then it is fused with the strain data of multiple first measuring points around the second measuring point (here is the measured data of the ground test itself). The specific fusion process is to construct a sample space, and then the strain data of the second measuring point is calculated using the adaptive modified Kriging interpolation method. During the interpolation process, the weight α of the virtual data 仿真 and the weight α of the measured data 试验:

[0043] α 仿真 =N 仿真 / (N 试验 *(N 试验 +N 仿真 ));

[0044] α 试验 =1 - α 仿真 .

[0045] Among them, N 仿真 is the number of measurement points of virtual data in the sample space, and N 试验 is the number of measurement points of measured data in the sample space.

[0046] In some alternative embodiments, the strain data of the node elements within the specified range are gradually searched for by a preset search radius and search increment, and both the search radius and the search increment are set to the average element scale during finite element simulation modeling.

[0047] In this embodiment, the screening of the simulation data needs to be based on the strain measurement point coordinates of the flight test and the ground static test. Through a preset search radius R (by default, the average element scale, specified during modeling), the node elements near the measurement points of the ground test and the flight test are circularly searched in the plane, and the simulation analysis strain data in the same measurement direction as the corresponding test is extracted. During the process of circularly expanding the search radius R, the single - search increment is 1 average element scale value, and the circular search will stop when the range covers all the node elements within the specified range.

[0048] By the above method, two ground - test strain fields and flight - test strain fields that can correspond one - by - one to the measurement points are reconstructed, and thus the consistency of the flight - test and ground - test data can be calculated in step S4.

[0049] In some alternative embodiments, in step S3, the set value is 5%.

[0050] In this embodiment, a consistency coefficient calculation method based on probability statistics is adopted. The proportion φ of the measurement points where the strain data (the strain data of the real measurement points + the virtual measurement points) of the ground test and the flight test within the evaluation area is less than 5% is used as the basis for evaluating the consistency of the ground - air tests.

[0051] In addition, the correlation determination of the strain - field distribution state can also be performed: The strain - field distribution correlation is mainly determined by the covariance of the strain data in the expanded ground - test and flight - test sample spaces, and the calculation expression is: , is the mean square deviation of the strain data in the ground - test and flight - test sample spaces, , is the strain of the i - th measurement point of the ground test, is the strain at the i-th measurement point of the flight test, is the correlation coefficient, m is the number of measurement points in the sample space, and pi takes the value of 2.

[0052] The consistency evaluation method provided by 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 evaluation results of the two test data, replacing the traditional rough judgment method based on the general distribution and trend of the data, and greatly improving the accuracy and reliability of the ground-air test consistency evaluation.

[0053] The second aspect of this application provides an aircraft ground test and flight test consistency evaluation device corresponding to the above method, which mainly includes:

[0054] A test data acquisition module, configured to acquire the strain data of each first measurement point of the ground test and acquire the strain data of each second measurement point of the flight test;

[0055] A test strain field reconstruction module, configured to fuse the finite element simulation data with the strain data of each first measurement point of the ground test, calculate the strain data of each second measurement point, and reconstruct the ground test strain field including the strain data of each first measurement point and each second measurement point. Similarly, fuse the finite element simulation data with the strain data of each second measurement point of the flight test, calculate the strain data of each first measurement point, and reconstruct the flight test strain field including the strain data of each first measurement point and each second measurement point;

[0056] A consistency evaluation module, configured to count the proportion of measurement points where the difference in strain data of the same measurement point is less than a set value in the reconstructed ground test strain field and flight test strain field, as the ground test and flight test consistency index.

[0057] In some alternative embodiments, the test data acquisition module includes:

[0058] An outlier rejection unit, configured to reject outliers in the strain data of each first measurement point of the ground test and reject outliers in the strain data of each second measurement point of the flight test.

[0059] In some alternative embodiments, the test strain field reconstruction module includes:

[0060] A second measurement point strain data calculation unit, configured to extract the strain data of the node elements within a specified range near the position of each second measurement point from the finite element simulation data, and jointly form a sample space centered on the second measurement point with the strain data of multiple first measurement points of the ground test. In the sample space, the adaptive modified Kriging interpolation method is used to calculate the strain data of the second measurement point;

[0061] The first measuring point strain data calculation unit is used to extract the strain data of the node elements within a specified range near each first measuring point position from the finite element simulation data, and jointly form a sample space centered on the first measuring point with the strain data of multiple second measuring points in the flight test. In the sample space, the strain data of the first measuring point is calculated by using the Kriging interpolation method with adaptive correction.

[0062] In some alternative embodiments, the strain data of the node elements within the specified range is gradually searched for by means of a preset search radius and a search increment, and both the search radius and the search increment are set to the average element scale during finite element simulation modeling.

[0063] In some alternative embodiments, the set value is 5%.

[0064] As mentioned above, the above are only specific embodiments 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 those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to 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 percentage of measuring points whose strain data difference of the same measuring point is less than the set value is counted as a consistency index between the ground test and the flight test; Wherein, 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.

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: 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.

4. 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%.

5. 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 percentage 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 the consistency index between the ground test and the flight test; Wherein, the experimental 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.

6. The aircraft ground test and flight test consistency assessment device according to claim 5, 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.

7. The aircraft ground test and flight test consistency assessment device according to claim 5, 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.

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

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