Aero-engine maneuvering load spectrum modeling method based on flight mission segment analysis

Abstract

The present invention discloses a method for modeling aero-engine maneuvering load spectrum based on flight mission segment analysis. First, the aero-engine load spectrum mission profile is decomposed and divided into various flight mission segments according to the flight phase and flight action. Second, each type of maneuvering mission segment is extracted, and the load characteristics of the maneuvering mission segment are comprehensively statistically analyzed. A generalized Pareto model is used to fit a mathematical model of the extreme value characteristics of the maneuvering mission segment. An exponential distribution model and a three-parameter Weibull model are used to fit a mathematical model of the load characteristics of the maneuvering mission segment. Based on the mathematical model, each type of maneuvering mission segment is further simulated. Finally, a simulation result of the maneuvering load spectrum is established based on the simulation results of each type of maneuvering mission segment, and the result is compared with a traditional aero-engine maneuvering load spectrum modeling and simulation method. The present invention effectively expands the statistical sample size of the maneuvering load characteristics and improves the simulation accuracy of the maneuvering load spectrum.

Description

Technical Field

[0001] The present invention relates to the technical field of aero-engine load spectrum, and in particular to a method for modeling aero-engine maneuvering load spectrum based on flight mission segment analysis. Background Art

[0002] When an aircraft engine operates alongside an aircraft, the aircraft's flight state and attitude will cause the engine to experience varying degrees of inertial load overload. For the entire aircraft engine, the maneuvering load spectrum generally refers to the engine's inertial overload spectrum. The normal overload spectrum is a typical aircraft engine maneuvering load spectrum and a typical load spectrum related to its use. Simulating an aircraft engine's load spectrum involves summarizing and statistically analyzing load characteristics, establishing a mathematical model of these load characteristics, and then obtaining load spectrum simulation results based on this mathematical model. The establishment of a mathematical model for the load characteristics of the maneuvering load spectrum and the simulation of the maneuvering load spectrum are important foundations for compiling maneuvering load spectra and are of significant engineering significance for the life research, life determination, and life extension of existing engines and components. Furthermore, the mathematical model and simulation results of the load characteristics of the maneuvering load spectrum are also an important foundation for predicting maneuvering flight load spectra and serve as a crucial basis for the life design, reliability testing, and life management of future newly developed engines. The compilation and prediction results of aircraft engine load spectra can provide a load basis for aircraft engine life design and testing. At present, the simulation research of maneuvering load spectrum in China generally takes the flight mission profile as the research object. By statistically analyzing the peak value, duration, waiting time and other load characteristics of maneuvering load based on the mission profile, a mathematical model of load characteristics is established. The main methods currently used for the simulation of maneuvering load spectrum of aircraft engines are:

[0003] The document "Operation-related Engine Load Spectrum Model and Simulation Research [J]. Propulsion Technology, 2000" statistically analyzed the load characteristic laws of a certain type of engine's center of gravity normal overload spectrum, used a Poisson random process to describe load characteristic parameters such as arrival time and duration, and used a half-sine signal to simulate the maneuvering load spectrum.

[0004] The document "Simulation of Maneuvering Flight Load Spectrum Based on Mission Segment Database [J]. Propulsion Technology, 2002" uses Poisson random process to establish the mathematical model of the duration and arrival time of the maneuvering flight load spectrum, uses three-parameter Weibull distribution to establish the mathematical model of the peak of the maneuvering flight load spectrum, extracts and establishes a maneuvering load segment database, and proposes a simulation method of the maneuvering flight load spectrum based on the database.

[0005] The patent number is: CN108717474A, and the name is "A method for compiling a comprehensive mission spectrum of an aircraft engine related to use". According to the load change characteristics, the maneuvering load is divided into five major typical mission segments. Each type of mission segment represents a type of load fragment with similar change characteristics. A mathematical model is established for each type of typical mission segment and the distribution parameters are obtained. The maneuvering load spectrum is simulated using a triangular wave.

[0006] The above-mentioned aero-engine load spectrum simulation methods all use flight mission profiles as their research objects. However, the load characteristics of mission profiles are very complex. Using mission profiles as units for statistical load characteristics reduces the number of statistical samples, which can easily lead to inaccurate statistical law fitting. On the other hand, it also fails to reflect the characteristics of maneuvering loads related to actual flight maneuvers. Therefore, the accuracy of maneuvering load characteristic statistics and maneuvering load spectrum simulation based on mission profiles is difficult to guarantee, and the important characteristics related to maneuvering load spectrum and flight maneuvers cannot be reflected. Therefore, it is necessary to provide a simple and effective aero-engine maneuvering load spectrum simulation method that can reflect the relationship between maneuvering loads and flight maneuvers, takes engine flight mission segments representing actual flight maneuvers as the research object, and is based on flight mission segment analysis. Summary of the Invention

[0007] In order to solve the above problems, the present invention proposes an aviation engine maneuvering load spectrum modeling method based on flight mission segment analysis, so as to change the current situation in which maneuvering load spectrum simulation is based on mission profiles, with insufficient statistical samples, inaccurate statistical law fitting, and inability to reflect the characteristics of maneuvering loads related to actual flight actions. It lays the foundation for the compilation of maneuvering load spectra of engine complete machines and components, and the prediction of maneuvering load spectra for new machine designs, and has important engineering significance for the life research and life determination and extension of engine complete machines and components.

[0008] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0009] The present invention is a method for modeling aero-engine maneuvering load spectrum based on flight mission segment analysis, comprising the following operations:

[0010] Collect flight mission profile data of aircraft engine measured load spectrum;

[0011] Decompose each mission profile data into flight mission segments, and extract various types of maneuvering mission segments based on the flight mission segment division results. The various types of maneuvering mission segments include deterministic maneuvering mission segments, maneuvering mission segments representing typical maneuvering flight actions, and connecting maneuvering mission segments.

[0012] Establish a mathematical model representing the extreme load characteristics of a typical maneuverable flight mission and verify the accuracy of the model;

[0013] Subdividing the flight mission segments, and then subdividing the maneuvering mission segments representing typical maneuvering flight actions according to the subdivision results of the flight mission segments;

[0014] Pre-process various types of maneuver mission segments;

[0015] Statistically analyze the load characteristics of the connecting maneuver mission segment, establish a mathematical model of the load characteristics of the connecting maneuver mission segment, and verify the accuracy of the model;

[0016] Statistically analyze the load characteristics of all types of maneuvering mission segments except the connecting maneuvering mission segments, establish mathematical models of the load characteristics of the corresponding maneuvering mission segments, and verify the accuracy of the models;

[0017] Based on the modeling results of the mathematical model of the load characteristics of various maneuvering mission segments, various maneuvering mission segments are simulated;

[0018] Based on the simulation results of various maneuver mission segments, the maneuver load spectrum is simulated;

[0019] The obtained maneuver load spectrum simulation results are compared with the conventional maneuver load spectrum simulation results based on mission profile analysis and the original maneuver load spectrum to verify the effectiveness of the simulation method and the accuracy of the simulation results.

[0020] A further improvement of the present invention is that: each flight mission profile data is decomposed, the flight mission segments are divided, and the corresponding class maneuvering mission segments are extracted according to the flight mission segment division results, including: each flight mission profile data is divided into deterministic load class flight mission segments and intermediate maneuvering action class flight mission segments, wherein the deterministic load class flight mission segments include takeoff, climb after takeoff, descent, landing small route, and landing class flight mission segments, and the intermediate maneuvering action class flight mission segments are the flight mission segments between the climb after takeoff segment and the descent segment in each flight mission profile, and the intermediate maneuvering action class flight mission segments are further divided into flight mission segments representing various actions according to the flight actions, including flight mission segments representing typical maneuvering flight actions and connection class flight mission segments representing the pilot's random operations for connecting the previous and next maneuvering flight actions, and the corresponding various types of maneuvering mission segments are extracted according to the flight mission segment division results.

[0021] A further improvement of the present invention is to establish a mathematical model representing the extreme load characteristics of a maneuvering mission segment of a typical maneuvering flight action, including: statistically analyzing the extreme load distribution characteristics reflecting the extreme load characteristics of various maneuvering mission segments representing typical maneuvering flight actions, and fitting the distribution of extreme load exceeding thresholds using a generalized Pareto model, wherein the expression of the generalized Pareto model is:

[0022]

[0023] Among them, y is the extreme load exceeding the threshold, y = xu, u is the extreme load extraction threshold, x is the extreme load extracted according to the extreme load extraction threshold u, ξ is the shape parameter of the generalized Pareto model, and σ is the scale parameter of the generalized Pareto model.

[0024] A further improvement of the present invention is that the flight mission segments are subdivided, including: subdividing the deterministic load-type flight mission segments according to the altitude and altitude change, and subdividing the intermediate maneuvering action-type flight mission segments representing typical maneuvering flight actions according to the action altitude, altitude change, speed, and angle change.

[0025] A further improvement of the present invention is that various types of maneuvering task segments are preprocessed, including: removing random disturbances and rain flow filtering, wherein random disturbances are removed from the divided task segments using 1 as a threshold, and then rain flow filtering is performed on the maneuvering task segments after random disturbance removal using 0.3 as a filtering threshold.

[0026] A further improvement of the present invention is that: the load characteristics of the connection-type maneuvering mission segment are statistically analyzed, and a mathematical model of the load characteristics of the connection-type maneuvering mission segment is established, including: statistics on the load characteristics of the connection-type flight mission segment, the load characteristics include duration distribution characteristics, waiting time distribution characteristics and fatigue load characteristics reflecting fatigue damage, wherein the fatigue load characteristics are the distribution characteristics of the load peak, the exponential distribution is used to fit the distribution of duration and waiting time to obtain the corresponding exponential distribution model, and the three-parameter Weibull distribution is used to fit the distribution of the peak to obtain the corresponding three-parameter Weibull distribution model.

[0027] A further improvement of the present invention is that: the load characteristics of the remaining types of maneuvering task segments except the connecting type maneuvering task segments are counted, and a mathematical model of the load characteristics of the corresponding types of maneuvering task segments is established, including: the load characteristics of the take-off and landing type maneuvering task segments are duration distribution characteristics, and the load characteristics of the remaining types of maneuvering task segments except the take-off and landing type maneuvering task segments and the connecting type maneuvering task segments are duration distribution characteristics, waiting time distribution characteristics, peak number, and peak distribution characteristics. The exponential distribution is used to fit the distribution of duration and waiting time to obtain the corresponding exponential distribution model, and the three-parameter Weibull distribution is used to fit the distribution of peak size to obtain the corresponding three-parameter Weibull distribution model.

[0028] A further improvement of the present invention is that: according to the modeling results of the mathematical model of the load characteristics of various maneuvering mission segments, various maneuvering mission segments are simulated, including: using the fitted exponential distribution model, taking random numbers to obtain the duration and waiting time, using the fitted three-parameter Weibull distribution model, taking random numbers to obtain the peak value, using a single sine wave to simulate the maneuvering mission segments of various single-load segments, and using the superposition of multiple sine waves to simulate the maneuvering mission segments of various multi-load segments.

[0029] A further improvement of the present invention is that: based on the simulation results of various maneuvering mission segments, the maneuvering load spectrum is simulated; specifically, based on the simulation results of various maneuvering mission segments, the simulation results of various maneuvering mission segments are spliced ​​according to the order and type of actions in the flight mission profile to obtain the simulation results of the maneuvering load spectrum based on the flight mission segment analysis.

[0030] The beneficial effects of the present invention are as follows: the present invention proposes a method for simulating aero-engine maneuvering load spectrum, breaking away from the traditional research method of taking mission profiles as research objects, and adopting flight mission segments divided based on flight actions as analysis and simulation objects, with each type of flight mission segment having independent load characteristics;

[0031] The present invention provides a more accurate method for statistical analysis of load characteristics of maneuvering mission segments. It adopts a more comprehensive load characteristic statistical method and a more accurate load characteristic mathematical model to effectively count the extreme load characteristics and fatigue load characteristics of aircraft engine maneuvering loads. The modeling results of various maneuvering mission segments obtained based on this method are used as the basis for the prediction and compilation of maneuvering load spectra, which can effectively improve the calculation accuracy of maneuvering load spectra.

[0032] The aero-engine maneuvering load spectrum simulation method based on flight mission segment analysis proposed in the present invention is concise, efficient and highly versatile. It can be applied to the simulation of maneuvering load spectra of various types and generations of aero-engines and has broad engineering application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a flow chart of the present invention;

[0034] Figure 2 is a division result of a certain mission profile in an embodiment of the present invention into a deterministic load-type flight mission segment and an intermediate maneuvering action-type flight mission segment;

[0035] Figure 3 is the load characteristic of the connecting maneuver mission segment in the embodiment of the present invention;

[0036] Figure 4 is the load characteristic of the other various types of maneuvering mission segments in the embodiment of the present invention;

[0037] Figure 5 is the simulation result of the connecting maneuver mission segment in the embodiment of the present invention;

[0038] Figure 6 This is the simulation result of the "mid-altitude subsonic circling one circle" type maneuver mission segment in the embodiment of the present invention;

[0039] Figure 7 This is the simulation result of the "mid-air subsonic turn followed by a 2000m dive" maneuver mission segment in an embodiment of the present invention;

[0040] Figure 8 is a simulation result of a maneuvering load spectrum based on flight mission segment analysis in an embodiment of the present invention;

[0041] Figure 9 is a comparison diagram of the simulation results of the maneuvering load spectrum in an embodiment of the present invention;

[0042] Figure 10 2. It is a schematic diagram of the accuracy test results of the mathematical model fitting of the extreme load characteristics of the "circling one circle" type maneuvering mission segment in an embodiment of the present invention;

[0043] Figure 11 2. It is a schematic diagram of the accuracy test results of the mathematical model fitting of the extreme load characteristics of the "2000m dive after turning" type maneuvering mission segment in an embodiment of the present invention;

[0044] Figure 12 2 is a schematic diagram of the model fitting accuracy test results of the waiting time distribution in an embodiment of the present invention;

[0045] Figure 13 2 is a schematic diagram of the model fitting accuracy test results of the total duration distribution in an embodiment of the present invention;

[0046] Figure 14 3 is a schematic diagram of the model fitting accuracy test results of the duration distribution of the load segments in the embodiment of the present invention;

[0047] Figure 15 4 is a schematic diagram of the model fitting accuracy test results of the peak distribution in the embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0049] The aircraft engine maneuvering load spectrum modeling method based on flight mission segment analysis of this embodiment includes the following operations:

[0050] Step 1: Collect flight mission profile data of the measured load spectrum of a certain type of aircraft engine; in this embodiment, 30 measured load spectrum flight mission profile data covering multiple mission types are collected, of which 29 measured load spectrum flight mission profile data are used for load characteristic statistics and maneuvering mission segment simulation, and 1 measured load spectrum flight mission profile data is used as the maneuvering load spectrum simulation object.

[0051] Step 2: Decompose each mission profile data, divide it into mission segments, and extract various types of maneuvering mission segments based on the flight mission segment division results. In this embodiment, the 29 measured load spectrum mission profile data collected in step 1 are decomposed and first divided into deterministic load-type mission segments and intermediate maneuvering action-type mission segments. The deterministic load-type mission segments include takeoff, climb after takeoff, descent, landing short route, and landing-type mission segments. The intermediate maneuvering action-type mission segments are the flight mission segments between the climb after takeoff and the descent in each profile. The division results are as follows: Figure 2 As shown. The intermediate maneuvering mission segments are further divided into flight mission segments representing various maneuvers based on the flight maneuvers. These include flight mission segments such as "circling," "combat turns," and "dogfights" representing typical maneuvering flight movements, and connecting flight mission segments representing random operations performed by the pilot to connect the preceding and following maneuvering flight movements. Based on the flight mission segment division results, corresponding maneuvering mission segments are extracted, including deterministic maneuvering mission segments, maneuvering mission segments representing typical maneuvering flight movements, and connecting maneuvering mission segments. In this embodiment, the normal overload parameter is used as a representative of the aircraft engine maneuvering load.

[0052] Step 3: Establish a mathematical model of the extreme load characteristics of the maneuvering mission segment representing a typical maneuvering flight action and verify the modeling accuracy. Specifically, the extreme load distribution characteristics of the maneuvering mission segment representing a typical maneuvering flight action are statistically analyzed, and the distribution of extreme load exceeding the threshold is fitted using a generalized Pareto model. The expression of the generalized Pareto model is:

[0053]

[0054] Among them, y is the extreme load exceeding the threshold, y = xu, u is the extreme load extraction threshold, x is the extreme load extracted according to the extreme load extraction threshold u, ξ is the shape parameter of the generalized Pareto model, and σ is the scale parameter of the generalized Pareto model.

[0055] In this embodiment, based on the generalized Pareto model, the mathematical model of the extreme load characteristics of the "circling" type maneuver mission segment has u = 2.1, ξ = 0.2169, σ = 0.4382, and the model fitting accuracy test results are as follows: Figure 10 As shown in the mathematical model of the extreme load characteristics of the "turn and dive 2000m" type maneuver mission segment, u = 2.2, ξ = -0.2757, ξ = -0.2757, and the model fitting accuracy test results are shown in Figure 11 shown.

[0056] Step 4: Subdivide the mission segments, and then further subdivide the mission segments representing typical maneuvers based on the mission segment segmentation results. In this embodiment, the deterministic payload mission segments are further subdivided based on altitude and altitude change, and the intermediate maneuver mission segments representing typical maneuvers are subdivided based on altitude, altitude change, speed, and angle change. The final mission segment segmentation results are shown in Table 1.

[0057] Table 1. The results of the maneuvering mission segment division of a certain mission profile

[0058]

[0059]

[0060] Step 5: Preprocess each type of maneuvering task segment. This includes removing random disturbances and performing rainflow filtering. Random disturbances are removed from the divided task segments using a threshold of 1, and rainflow filtering is performed on the maneuvering task segments after random disturbance removal using a filtering threshold of 0.3.

[0061] Step 6: The load characteristics of the pre-processed connecting maneuver mission segments representing the pilot's random operations for connecting the preceding and following maneuvering flight actions are statistically analyzed. The load characteristics are as follows: Figure 3 As shown in the figure, it mainly includes the duration distribution characteristics, the waiting time distribution characteristics and the fatigue load characteristics reflecting fatigue damage. The fatigue load characteristics are the distribution characteristics of the load peak. The exponential distribution is used to fit the distribution of duration and waiting time, and the three-parameter Weibull distribution is used to fit the distribution of peak value. The expression of the exponential distribution is:

[0062]

[0063] Where a, b, c are the parameters of the quadratic exponential distribution, and T is the duration or waiting time;

[0064] The expression of the three-parameter Weibull distribution is:

[0065]

[0066] Among them, η is the location parameter, α is the scale parameter, β is the shape parameter, and f is the peak value.

[0067] The parameters of the quadratic exponential distribution of the waiting time distribution in this embodiment are: a=-2.3679e-6, b=0.0268, c=0.0331, and the model fitting accuracy test results are as follows: Figure 12 The parameters of the quadratic exponential distribution of the total duration distribution are: a = -2.9281e-5, b = 0.0265, c = 0.0880, and the model fitting accuracy test results are shown in Figure 13 The parameters of the quadratic exponential distribution of the duration of the load segment are: a = -0.0023, b = 0.1955, c = -0.1094, and the model fitting accuracy test results are shown in Figure 14 The peak distribution parameters are: η = 1.3000, α = 0.3338, β = 0.8321, and the model fitting accuracy test results are shown in Figure 15 shown.

[0068] Step 7: Statistically analyze the load characteristics of all types of maneuvering mission segments after preprocessing, including those of the connecting maneuvering mission segments, establish a mathematical model of the load characteristics of the corresponding maneuvering mission segments, and perform a model fitting accuracy test. Figure 4 As shown, it mainly includes duration distribution characteristics, waiting time distribution characteristics, and fatigue load characteristics reflecting fatigue damage. Among them, the load characteristics of take-off and landing maneuvering mission segments are duration distribution characteristics, and the load characteristics of other types of maneuvering mission segments are duration distribution characteristics, waiting time distribution characteristics, peak number, and peak distribution characteristics. The exponential distribution is used to fit the distribution of duration and waiting time to obtain the corresponding exponential distribution model. The three-parameter Weibull distribution is used to fit the distribution of peak size to obtain the corresponding three-parameter Weibull distribution model. In this embodiment, the maneuvering mission segments of "subsonic circling in mid-air for one circle" and "subsonic turning in mid-air and diving 2000m" are taken as examples to conduct statistics and modeling. The results are shown in Table 2;

[0069] Table 2 Modeling results of mathematical models for load characteristics of two types of maneuvering mission segments

[0070]

[0071] Based on the above modeling results, the mathematical models of the load characteristics of the "medium-altitude subsonic circling for one circle" and "medium-altitude subsonic turning and then diving 2000m" maneuvering mission segments were tested for model fitting accuracy.

[0072] Step 8: Based on the mathematical modeling results of the load characteristics of each maneuvering mission segment, simulate each maneuvering mission segment. Specifically, the following steps are used: using the fitted exponential distribution model to take random numbers to obtain the duration and waiting time, using the fitted three-parameter Weibull distribution model to take random numbers to obtain the peak value, and the simulation results of the connecting maneuvering mission segment are as follows: Figure 5 As shown in the figure, since the “mid-altitude subsonic circling for one circle” type maneuvering mission segment is a single-load segment mission segment, a single sine wave is used to simulate it, and the “mid-altitude subsonic turn and then dive 2000m” type maneuvering mission segment is a dual-load segment mission segment, which is simulated by superposition of two sine waves. The simulation results of the two types of maneuvering mission segments are shown in Figure 1. Figure 6 and Figure 7 shown.

[0073] Step 9, based on the simulation results of various maneuvering mission segments, simulate the maneuvering load spectrum. Specifically, it includes: based on the simulation results of various maneuvering mission segments obtained in the above steps, the simulation results of various maneuvering mission segments are spliced ​​according to the order and type of actions in the profile, and finally the simulation results of the maneuvering load spectrum based on the flight mission segment analysis are obtained. In this embodiment, the maneuvering load spectrum mission profile shown in Table 1 is simulated, and the results are as follows: Figure 8 shown.

[0074] Step 10 compares the obtained maneuver load spectrum simulation results with conventional maneuver load spectrum simulation results based on mission profile analysis, and the original maneuver load spectrum to verify the effectiveness of the simulation method and the accuracy of the simulation results. Specifically, this includes comparing the maneuver load spectrum simulation results based on flight mission segment analysis of this embodiment with conventional maneuver load spectrum simulation results based on mission profile analysis, and the original maneuver load spectrum. The maneuver load spectrum simulation based on mission profile analysis uses 29 mission profiles as statistical units, divides the maneuver load segments in the mission profiles into five categories: single small peak, single large peak, double peak, triple peak, and multiple peaks, and performs load feature statistics and fitting on each of these load segments. The mission profiles of the "circling a circle" type maneuver mission segment and the "turning and diving 2000m" type maneuver mission segment were statistically analyzed, and it was found that the mission profile is composed of 12 single small peak load segments, 14 single large peak load segments, and 1 double peak load segment. Therefore, random values ​​are taken according to the fitting results and randomly spliced ​​according to the number ratio of these types of maneuver load segments to obtain the simulation results of the maneuver load spectrum based on mission profile analysis; the simulation results based on flight mission segment analysis and mission profile analysis are compared with the measured maneuver profiles. The simulation comparison results are shown in Figure 2. Figure 9 The comparison results of the cycle characteristics are shown in Table 3;

[0075] Table 3 Comparison of cyclic characteristics of maneuver load spectrum simulation results

[0076]

[0077]

[0078] As can be seen from Table 3, the results of maneuver load spectrum modeling and simulation based on flight mission segment analysis are more accurate, while the simulation results based on mission profile analysis have a large cyclic error compared with the original maneuver load spectrum profile. This verifies the effectiveness of the simulation method proposed in this paper and the accuracy of the simulation results.

[0079] This invention provides an accurate, comprehensive, and effective method for calculating the statistical characteristics of aircraft engine maneuvering loads. By using flight mission segments with independent load characteristics as modeling and simulation targets, this method effectively expands the statistical sample size of maneuvering load characteristics and improves the simulation accuracy of maneuvering load spectra. This method is of great significance for compiling aircraft engine load spectra, performing strength analysis, and studying aircraft engine lifespan. The method is concise, efficient, and highly versatile, and therefore has broad engineering application value.

[0080] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with their meanings in the context of the prior art and, unless defined similarly as herein, will not be interpreted in an idealized or overly formal sense.

[0081] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An aero-engine maneuvering load spectrum modeling method based on flight mission segment analysis is characterized by: The following operations are included: Collect flight mission profile data of aircraft engine measured load spectrum; Decompose each mission profile data into flight mission segments, and extract various types of maneuvering mission segments based on the flight mission segment division results. The various types of maneuvering mission segments include deterministic maneuvering mission segments, maneuvering mission segments representing typical maneuvering flight actions, and connecting maneuvering mission segments. Establish a mathematical model representing the extreme load characteristics of a typical maneuverable flight mission and verify the accuracy of the model; Subdividing the flight mission segments, and then subdividing the maneuvering mission segments representing typical maneuvering flight actions according to the subdivision results of the flight mission segments; Pre-process various types of maneuver mission segments; Statistically analyze the load characteristics of the connecting maneuver mission segment, establish a mathematical model of the load characteristics of the connecting maneuver mission segment, and verify the accuracy of the model; Statistically analyze the load characteristics of all types of maneuvering mission segments except the connecting maneuvering mission segments, establish mathematical models of the load characteristics of the corresponding maneuvering mission segments, and verify the accuracy of the models; Based on the modeling results of the mathematical model of the load characteristics of various maneuvering mission segments, various maneuvering mission segments are simulated; Based on the simulation results of various maneuver mission segments, the maneuver load spectrum is simulated; The obtained maneuver load spectrum simulation results are compared with those of conventional maneuver load spectrum simulation results based on mission profile analysis and the original maneuver load spectrum to verify the effectiveness of the simulation method and the accuracy of the simulation results. The method of establishing a mathematical model for the extreme load characteristics of a maneuvering mission segment representing a typical maneuvering flight action includes: statistically analyzing the extreme load distribution characteristics of various maneuvering mission segments representing typical maneuvering flight actions that reflect the extreme load characteristics, and fitting the distribution of the extreme load exceeding the threshold using a generalized Pareto model, wherein the generalized Pareto model is expressed as: Among them, y is the extreme load exceeding the threshold, y = xu, u is the extreme load extraction threshold, x is the extreme load extracted according to the extreme load extraction threshold u, ξ is the shape parameter of the generalized Pareto model, and σ is the scale parameter of the generalized Pareto model.

2. The method for modeling aero-engine maneuvering load spectrum based on flight mission segment analysis according to claim 1, characterized in that: The decomposition of each flight mission profile data, the division of flight mission segments, and the extraction of corresponding various types of maneuvering mission segments based on the division results of the flight mission segments include: dividing each flight mission profile data into deterministic load-type flight mission segments and intermediate maneuvering action flight mission segments, wherein the deterministic load-type flight mission segments include takeoff, climb after takeoff, descent, landing small route, and landing flight mission segments; the intermediate maneuvering action flight mission segments are the flight mission segments between the climb after takeoff and the descent segment in each flight mission profile; the intermediate maneuvering action flight mission segments are further divided into flight mission segments representing various actions based on the flight actions, including flight mission segments representing typical maneuvering flight actions and connection-type flight mission segments representing random operations performed by the pilot for connecting previous and subsequent maneuvering flight actions; and the corresponding various types of maneuvering mission segments are extracted based on the division results of the flight mission segments.

3. The method for modeling aero-engine maneuvering load spectrum based on flight mission segment analysis according to claim 1, characterized in that: The subdividing of the flight mission segments includes: subdividing the deterministic load-type flight mission segments according to the altitude and altitude change, and subdividing the intermediate maneuvering action-type flight mission segments representing typical maneuvering flight actions according to the action altitude, altitude change, speed, and angle change.

4. The method for modeling aero-engine maneuvering load spectrum based on flight mission segment analysis according to claim 1, characterized in that: The preprocessing of various types of maneuvering task segments includes: removing random disturbances and rain flow filtering, wherein random disturbances are removed from the divided task segments using 1 as a threshold, and then rain flow filtering is performed on the maneuvering task segments after random disturbance removal using 0.3 as a filtering threshold.

5. The method for modeling aero-engine maneuvering load spectrum based on flight mission segment analysis according to claim 1, characterized in that: The method of statistically analyzing the load characteristics of the connection-type maneuvering mission segment and establishing a mathematical model of the load characteristics of the connection-type maneuvering mission segment includes: statistically analyzing the load characteristics of the connection-type flight mission segment, the load characteristics include duration distribution characteristics, waiting time distribution characteristics and fatigue load characteristics reflecting fatigue damage, wherein the fatigue load characteristics are the distribution characteristics of the load peak, using exponential distribution to fit the distribution of duration and waiting time to obtain a corresponding exponential distribution model, and using three-parameter Weibull distribution to fit the distribution of peak value to obtain a corresponding three-parameter Weibull distribution model.

6. The method for modeling aero-engine maneuvering load spectrum based on flight mission segment analysis according to claim 5, characterized in that: The statistical load characteristics of all types of maneuvering mission segments except the connecting maneuvering mission segments are used to establish a mathematical model of the load characteristics of the corresponding maneuvering mission segments, including: the load characteristics of the take-off and landing maneuvering mission segments are duration distribution characteristics, the load characteristics of all types of maneuvering mission segments except the take-off and landing maneuvering mission segments and the connecting maneuvering mission segments are duration distribution characteristics, waiting time distribution characteristics, peak number, and peak distribution characteristics. The exponential distribution is used to fit the distribution of duration and waiting time to obtain the corresponding exponential distribution model, and the three-parameter Weibull distribution is used to fit the distribution of peak size to obtain the corresponding three-parameter Weibull distribution model.

7. The method for modeling aero-engine maneuvering load spectrum based on flight mission segment analysis according to claim 6, characterized in that: The various maneuvering mission segments are simulated based on the mathematical model modeling results of the load characteristics of the various maneuvering mission segments, including: using the fitted exponential distribution model to obtain the duration and waiting time by taking random numbers, using the fitted three-parameter Weibull distribution model to obtain the peak value by taking random numbers, using a single sine wave to simulate the maneuvering mission segments of various single-load segments, and using the superposition of multiple sine waves to simulate the maneuvering mission segments of various multi-load segments.

8. The method for modeling aero-engine maneuvering load spectrum based on flight mission segment analysis according to claim 1, characterized in that: Based on the simulation results of various maneuvering mission segments, the maneuvering load spectrum is simulated; specifically, based on the simulation results of various maneuvering mission segments, the simulation results of various maneuvering mission segments are spliced ​​according to the order and type of actions in the flight mission profile to obtain the simulation results of the maneuvering load spectrum based on the flight mission segment analysis.

Images