Aircraft engine exhaust passage thermal vibration load spectrum compilation method and system

Abstract

The invention belongs to the technical field of aircraft engine exhaust passage design, and particularly relates to an aircraft engine exhaust passage thermal vibration load spectrum compilation method and system, and the method comprises the steps: 1, determining a typical mission profile of an aircraft and the proportion of the typical mission profile; step 2, determining durations of different engine typical states under each aircraft typical mission profile; 3, counting the total duration of different engine typical states under each aircraft typical mission profile, and constructing an engine typical state-time spectrum; 4, determining temperature loads and vibration loads of the exhaust passage in different typical states of the engine, and constructing a typical state-thermal / vibration load spectrum of the engine; and step 5, integrating the engine typical state-time spectrum and the engine typical state-thermal / vibration load spectrum to obtain a thermal / vibration load-time spectrum about the exhaust passage, and completing compilation of the thermal / vibration load spectrum of the aircraft engine exhaust passage.

Description

Technical Field

[0001] The present application belongs to the technical field of aircraft engine exhaust duct design, and specifically relates to a method and system for compiling a thermal vibration load spectrum of an aircraft engine exhaust duct. Background Art

[0002] The exhaust duct of an aircraft engine is in a vibration environment caused by the pressure pulsation of the engine tail jet for a long time. At the same time, the thermal environment is superimposed, which easily causes thermal vibration fatigue damage.

[0003] Thermal vibration load spectrum is an important condition for thermal vibration fatigue resistance design of aircraft engine exhaust duct structure. However, currently, there is a lack of reasonable and feasible method for compiling thermal vibration load spectrum of aircraft engine exhaust duct. In view of this, this application is proposed. Summary of the invention

[0004] The purpose of the present application is to provide a method and system for compiling a thermal vibration load spectrum of an aircraft engine exhaust duct, so as to overcome or alleviate at least one aspect of the known technical defects.

[0005] The technical solution of this application is:

[0006] On the one hand, a method for compiling a thermal vibration load spectrum of an aircraft engine exhaust duct is provided, comprising:

[0007] Step 1: Determine the aircraft's typical mission profile and its proportion;

[0008] Step 2: Determine the duration of typical engine states under typical mission profiles of each aircraft;

[0009] Step 3: Count the total duration of different engine typical states under each aircraft's typical mission profile, and construct the engine typical state-time spectrum;

[0010] Step 4: determine the temperature load and vibration load of the exhaust duct under different typical engine states, and construct a typical engine state-heat / vibration load spectrum;

[0011] Step 5: Integrate the typical engine state-time spectrum and the typical engine state-heat / vibration load spectrum to obtain the heat / vibration load-time spectrum of the exhaust duct, and complete the compilation of the thermal vibration load spectrum of the aircraft engine exhaust duct.

[0012] According to at least one embodiment of the present application, in the above-mentioned method for compiling the thermal vibration load spectrum of the aircraft engine exhaust duct, in step one, by collecting and sorting out the training and usage of similar / similar aircraft models, the aircraft usage tasks are determined from the perspective of covering all training and tasks, the aircraft usage tasks are analyzed, the load characteristics of the aircraft usage tasks are analyzed, similar aircraft usage tasks are merged, and the typical mission profile of the aircraft is determined.

[0013] According to at least one embodiment of the present application, in the above-mentioned method for compiling a thermal vibration load spectrum for an aircraft engine exhaust duct, in step two, the engine states are classified and combined according to the impact of the engine on the thermal and vibration environment of the exhaust duct, and a typical engine state is selected.

[0014] According to at least one embodiment of the present application, in the above-mentioned method for compiling a thermal vibration load spectrum of an aircraft engine exhaust duct, in step 2, typical engine states include an idling state, a rated power state, and a take-off state.

[0015] According to at least one embodiment of the present application, in the above-mentioned method for compiling a thermal vibration load spectrum of an aircraft engine exhaust duct, in step three, the temperature load and vibration load of the exhaust duct under different typical engine conditions are determined during the design phase by referring to the vibration environment test results and temperature spectra of similar aircraft.

[0016] According to at least one embodiment of the present application, in the above-mentioned method for compiling the thermal vibration load spectrum of the exhaust duct of an aircraft engine, in step three, the vibration load is given in the form of pulsating pressure or sound pressure in the exhaust duct, and the temperature load is given in the form of temperature distribution or temperature peak of the inner wall of the exhaust duct.

[0017] On the other hand, a system for compiling thermal vibration load spectrum of an aircraft engine exhaust duct is provided, comprising:

[0018] A module for determining the typical mission profile of an aircraft and its proportion, used to determine the typical mission profile of an aircraft and its proportion;

[0019] The engine typical state duration determination module is used to determine the duration of different engine typical states under each aircraft's typical mission profile;

[0020] The engine typical state-time spectrum construction module is used to count the total duration of different engine typical states under each aircraft's typical mission profile and construct the engine typical state-time spectrum;

[0021] Engine typical state - thermal / vibration load spectrum construction module, used to determine the temperature load and vibration load of the exhaust duct under different engine typical states, and construct the engine typical state - thermal / vibration load spectrum;

[0022] The thermal / vibration load-time spectrum compilation module is used to integrate the engine typical state-time spectrum and the engine typical state-thermal / vibration load spectrum to obtain the thermal / vibration load-time spectrum of the exhaust duct, and complete the compilation of the thermal vibration load spectrum of the aircraft engine exhaust duct.

[0023] According to at least one embodiment of the present application, in the above-mentioned aircraft engine exhaust duct thermal vibration load spectrum compilation system, in the aircraft typical mission profile and its proportion determination module, by collecting and sorting out the training and use of similar / similar aircraft models, the aircraft usage tasks are determined from the perspective of covering all training and tasks, the aircraft usage mission load characteristics are analyzed, and similar aircraft usage tasks are merged to determine the aircraft typical mission profile.

[0024] According to at least one embodiment of the present application, in the above-mentioned aircraft engine exhaust duct thermal vibration load spectrum compilation system, in the engine typical state duration determination module, the engine states are classified and merged according to the engine's impact on the exhaust duct thermal and vibration environment, and a typical engine state is selected.

[0025] According to at least one embodiment of the present application, in the above-mentioned aircraft engine exhaust duct thermal vibration load spectrum compilation system, in the engine typical state duration determination module, the engine typical state includes an idling state, a rated power state, and a take-off state.

[0026] According to at least one embodiment of the present application, in the above-mentioned aircraft engine exhaust duct thermal vibration load spectrum compilation system, in the engine typical state-time spectrum construction module, the temperature load and vibration load of the exhaust duct under different engine typical states are determined during the design stage with reference to the vibration environment test results and temperature spectra of similar aircraft.

[0027] According to at least one embodiment of the present application, in the above-mentioned aircraft engine exhaust duct thermal vibration load spectrum compilation system, in the engine typical state-time spectrum construction module, the vibration load is given in the form of pulsating pressure or sound pressure in the exhaust duct, and the temperature load is given in the form of temperature distribution or temperature peak of the inner wall of the exhaust duct.

[0028] This application has at least the following beneficial technical effects:

[0029] Provided are a method and system for compiling a thermal vibration load spectrum for an aircraft engine exhaust duct. The exhaust duct thermal / vibration load spectrum is compiled based on the typical state of the engine, forming a thermal / vibration load spectrum of the aircraft exhaust duct structure based on the typical state of the engine, which can provide a basis for the vibration fatigue design of the aircraft engine exhaust duct structure in a heat-resistant environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of a method for compiling a thermal vibration load spectrum of an aircraft engine exhaust duct provided in an embodiment of the present application;

[0031] Figure 2 is a schematic diagram of the vibration dynamic load of the engine at an idling state provided by an embodiment of the present application;

[0032] Figure 3is a schematic diagram of the vibration dynamic load of the engine under rated power state provided by an embodiment of the present application;

[0033] Figure 4 is a schematic diagram of the vibration dynamic load of the engine in the take-off state provided by an embodiment of the present application;

[0034] Figure 5 It is a schematic diagram of a system for compiling a thermal vibration load spectrum for an aircraft engine exhaust duct provided in an embodiment of the present application.

[0035] In order to better illustrate the present embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. In addition, the drawings are only used for illustrative purposes and should not be construed as limitations on the present application. DETAILED DESCRIPTION

[0036] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be described in further detail in detail and in detail with reference to the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design.

[0037] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application shall have the usual meanings understood by those of ordinary skill in the art to which this application belongs. The words used in the description of this application to indicate orientation are only used to indicate relative directions or positional relationships. When the absolute position of the described object changes, its relative positional relationship may also change accordingly. The word "include" used in the description of this application indicates that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, but does not exclude other elements or objects.

[0038] In addition, it should be noted that, unless otherwise clearly specified and limited, the words "installation", "connection" and similar terms used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Technical personnel in the field can understand its specific meaning in this application according to the specific circumstances.

[0039] A method for compiling thermal vibration load spectrum of aircraft engine exhaust duct, such as Figure 1 shown.

[0040] Step 1: Determine the aircraft's typical mission profile and its proportion.

[0041] Typical aircraft missions are determined by how the aircraft is designed and used.

[0042] The design usage of the aircraft is determined according to the technical requirements, represents the expected usage of the aircraft, and consists of the following:

[0043] Task type;

[0044] Task mixing;

[0045] Mission profiles for each mission type, which are divided into mission segments according to flight phases, such as taxi, climb, cruise, low altitude, descent, etc., with duration, altitude, speed and payload layout requirements specified for each mission segment;

[0046] The number of flights for each mission.

[0047] When determining the typical mission of an aircraft, the overall mission requirements, future deployment plans and usage of the aircraft are taken into consideration.

[0048] The typical tasks of an aircraft can be determined by referring to the training syllabus and field usage of similar aircraft.

[0049] By collecting and sorting out the training and use of similar / close aircraft models, we can determine the aircraft's usage tasks from the perspective of covering all training and tasks, analyze the aircraft's usage mission load characteristics, merge similar aircraft usage tasks, and determine the aircraft's typical mission profile.

[0050] Step 2: Determine the duration of typical engine states under typical mission profiles of each aircraft.

[0051] According to the impact of the engine on the thermal and vibration environment of the exhaust duct, the engine states are classified and combined, and a typical engine state is selected.

[0052] Typical engine states include idling state, rated power state, and take-off state.

[0053] According to the aircraft's usage characteristics and profile flight parameters, determine the duration of different engine typical states under each aircraft's typical mission profile.

[0054] In particular, when determining the duration of the typical state of the engine, the effect time of the engine running on the ground is taken into account. The cumulative effect time is taken as 15 minutes for every 50 flight hours when the aircraft is taxiing at maximum power on the ground. The cumulative effect time is taken as 15 minutes for every 50 flight hours when the engine is running at maximum power on the ground. It is added to the duration of the take-off state. The increase method can be referred to as follows:

[0055] According to the take-off and landing and time proportion of the aircraft's typical mission, add it to the take-off status of each aircraft's typical mission, or directly add it to the take-off status of the selected single aircraft's typical mission, but ensure that the total proportion meets the requirements.

[0056] Step 3: Count the total duration of different engine typical states under each aircraft's typical mission profile and construct the engine typical state-time spectrum.

[0057] Step 4: Determine the temperature load and vibration load of the exhaust duct under different typical engine conditions, and construct the engine typical condition-heat / vibration load spectrum.

[0058] The temperature load and vibration load of the exhaust duct under typical conditions of different engines can be determined during the design phase by referring to the vibration environment test results and temperature spectrum of similar aircraft.

[0059] According to the characteristics of the exhaust duct, the vibration load is generally given in the form of pulsating pressure or sound pressure in the exhaust duct, and the temperature load is generally given in the form of temperature distribution or temperature peak on the inner wall of the exhaust duct.

[0060] The engineering prediction method is used to compile the engine's typical state - thermal / vibration load spectrum. The processing of vibration loads can refer to GJB / Z 126-1999.

[0061] Step 5: Integrate the typical engine state-time spectrum and the typical engine state-heat / vibration load spectrum to obtain the heat / vibration load-time spectrum of the exhaust duct, and complete the compilation of the thermal vibration load spectrum of the aircraft engine exhaust duct.

[0062] In a specific example, the method for compiling a thermal vibration load spectrum of an aircraft engine exhaust duct disclosed in the above embodiment is implemented as follows:

[0063] S1. Collect and sort out the training and use of similar / similar aircraft models, determine the use tasks from the perspective of covering all training and tasks, analyze the load characteristics, merge similar uses, and determine the typical tasks of the aircraft and their proportions, as shown in the following table:

[0064] For the convenience of calculation, the takeoff and landing can be given as a spectrum block, such as 100 takeoffs and landings. The typical tasks and time of each aircraft in a spectrum block are shown in the following table:

[0065] S2. According to the impact of the engine on the exhaust duct heat and vibration environment, the engine status is classified and merged, and typical engine status is selected, including the idling status, the rated power status, and the take-off status. The duration of different engine typical statuses under the typical mission profile of each aircraft is determined, as shown in the following table:

[0066] S3. Count the total duration of different typical engine states under each aircraft's typical mission profile, and construct the engine's typical state-time spectrum, as shown in the following table:

[0067] S4. According to the vibration environment and temperature environment data of the typical state of the engine, the vibration load spectrum and temperature load spectrum of the exhaust duct are determined, and the vibration load and temperature spectrum are compiled using the engineering prediction method to construct the typical state-time spectrum of the engine.

[0068] The vibration load is given in the form of pulsating pressure in the exhaust duct, and the temperature load is generally given in the form of peak temperature of the exhaust duct wall.

[0069] S5. Combine the typical engine state-time spectrum and the typical engine state-heat / vibration load spectrum to obtain the heat / vibration load-time spectrum of the exhaust duct, and complete the compilation of the heat / vibration load spectrum of the aircraft engine exhaust duct, as shown in the following table:

[0070] A system for compiling a thermal vibration load spectrum for an exhaust duct of an aircraft engine, used to implement the method for compiling a thermal vibration load spectrum for an exhaust duct of an aircraft engine disclosed in the above embodiment, comprising:

[0071] A module for determining the typical mission profile of an aircraft and its proportion, used to determine the typical mission profile of an aircraft and its proportion;

[0072] The engine typical state duration determination module is used to determine the duration of different engine typical states under each aircraft's typical mission profile;

[0073] The engine typical state-time spectrum construction module is used to count the total duration of different engine typical states under each aircraft's typical mission profile and construct the engine typical state-time spectrum;

[0074] Engine typical state - thermal / vibration load spectrum construction module, used to determine the temperature load and vibration load of the exhaust duct under different engine typical states, and construct the engine typical state - thermal / vibration load spectrum;

[0075] The thermal / vibration load-time spectrum compilation module is used to integrate the engine typical state-time spectrum and the engine typical state-thermal / vibration load spectrum to obtain the thermal / vibration load-time spectrum of the exhaust duct, and complete the compilation of the thermal vibration load spectrum of the aircraft engine exhaust duct.

[0076] Optionally, in the above-mentioned aircraft engine exhaust duct thermal vibration load spectrum compilation system, in the aircraft typical mission profile and its proportion determination module, by collecting and sorting out the training and usage of similar / similar aircraft models, the aircraft usage tasks are determined from the perspective of covering all training and tasks, the aircraft usage mission load characteristics are analyzed, and similar aircraft usage tasks are merged to determine the aircraft typical mission profile.

[0077] Optionally, in the above-mentioned aircraft engine exhaust duct thermal vibration load spectrum compilation system, in the engine typical state duration determination module, the engine states are classified and combined according to the engine's impact on the exhaust duct thermal and vibration environment, and a typical engine state is selected.

[0078] Optionally, in the above-mentioned aircraft engine exhaust duct thermal vibration load spectrum compilation system, in the engine typical state duration determination module, the engine typical state includes an idling state, a rated power state, and a take-off state.

[0079] Optionally, in the above-mentioned aircraft engine exhaust duct thermal vibration load spectrum compilation system, in the engine typical state-time spectrum construction module, the temperature load and vibration load of the exhaust duct under different engine typical states are determined during the design phase with reference to the vibration environment test results and temperature spectra of similar aircraft.

[0080] Optionally, in the above-mentioned aircraft engine exhaust duct thermal vibration load spectrum compilation system, in the engine typical state-time spectrum construction module, the vibration load is given in the form of pulsating pressure or sound pressure in the exhaust duct, and the temperature load is given in the form of temperature distribution or temperature peak of the inner wall of the exhaust duct.

[0081] The method and system for compiling a thermal vibration load spectrum for an aircraft engine exhaust duct disclosed in the above-mentioned embodiment compiles the exhaust duct thermal / vibration load spectrum based on the typical state of the engine, thereby forming a thermal / vibration load spectrum for the aircraft exhaust duct structure based on the typical state of the engine, which can provide a basis for the vibration fatigue design of the aircraft engine exhaust duct structure in a heat-resistant environment.

[0082] In addition, technicians in the field should also be able to realize that the various modules of the aircraft engine exhaust duct thermal vibration load spectrum compilation system disclosed in the embodiments of the present application can be implemented by electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, this application generally describes them according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Technicians in the field can choose to adopt different methods to implement the described functions for each specific application and its actual constraints, but such implementation should not be considered to be beyond the scope of this application.

[0083] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other. In the absence of conflict, the embodiments in this application and the technical features in the embodiments can be combined with each other to obtain new embodiments.

[0084] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the scope of protection of the present application.

Claims

1. A method for compiling a thermal vibration load spectrum of an aircraft engine exhaust duct, characterized in that: include: Step 1: Determine the aircraft's typical mission profile and its proportion; Step 2: Determine the duration of typical engine states under typical mission profiles of each aircraft; Step 3: Count the total duration of different engine typical states under each aircraft's typical mission profile, and construct the engine typical state-time spectrum; Step 4: determine the temperature load and vibration load of the exhaust duct under different typical engine states, and construct a typical engine state-heat / vibration load spectrum; Step 5: Integrate the typical engine state-time spectrum and the typical engine state-heat / vibration load spectrum to obtain the heat / vibration load-time spectrum of the exhaust duct, and complete the compilation of the thermal vibration load spectrum of the aircraft engine exhaust duct.

2. The method for compiling thermal vibration load spectrum of an aircraft engine exhaust duct according to claim 1, characterized in that: In step one, by collecting and sorting out the training and use of similar / close aircraft models, the aircraft usage tasks are determined from the perspective of covering all training and tasks, the aircraft usage missions are analyzed, the load characteristics of the aircraft usage missions are analyzed, similar aircraft usage missions are merged, and the typical mission profile of the aircraft is determined.

3. The method for compiling thermal vibration load spectrum of an aircraft engine exhaust duct according to claim 2 is characterized in that: In step 2, the engine states are classified and combined according to the impact of the engine on the thermal and vibration environment of the exhaust duct, and a typical engine state is selected.

4. The method for compiling thermal vibration load spectrum of an aircraft engine exhaust duct according to claim 3 is characterized in that: In step 2, typical engine states include idling state, rated power state, and take-off state.

5. The method for compiling thermal vibration load spectrum of an aircraft engine exhaust duct according to claim 4 is characterized in that: In step three, the temperature load and vibration load of the exhaust duct under different typical engine conditions are determined during the design phase by referring to the vibration environment test results and temperature spectrum of similar aircraft.

6. The method for compiling thermal vibration load spectrum of an aircraft engine exhaust duct according to claim 5, characterized in that: In step three, the vibration load is given in the form of pulsating pressure or sound pressure in the exhaust duct, and the temperature load is given in the form of temperature distribution or temperature peak of the inner wall of the exhaust duct.

7. A system for compiling thermal vibration load spectrum of aircraft engine exhaust duct, characterized in that: include: A module for determining the typical mission profile of an aircraft and its proportion, used to determine the typical mission profile of an aircraft and its proportion; The engine typical state duration determination module is used to determine the duration of different engine typical states under each aircraft's typical mission profile; The engine typical state-time spectrum construction module is used to count the total duration of different engine typical states under each aircraft's typical mission profile and construct the engine typical state-time spectrum; Engine typical state - thermal / vibration load spectrum construction module, used to determine the temperature load and vibration load of the exhaust duct under different engine typical states, and construct the engine typical state - thermal / vibration load spectrum; The thermal / vibration load-time spectrum compilation module is used to integrate the engine typical state-time spectrum and the engine typical state-thermal / vibration load spectrum to obtain the thermal / vibration load-time spectrum of the exhaust duct, and complete the compilation of the thermal vibration load spectrum of the aircraft engine exhaust duct.

8. The aircraft engine exhaust duct thermal vibration load spectrum compilation system according to claim 7, characterized in that: In the module for determining the aircraft's typical mission profile and its proportion, the aircraft's usage tasks are determined from the perspective of covering all training and tasks by collecting and sorting out the training and usage of similar / close aircraft models, analyzing the aircraft's usage mission load characteristics, merging similar aircraft usage tasks, and determining the aircraft's typical mission profile.

9. The aircraft engine exhaust duct thermal vibration load spectrum compilation system according to claim 8, characterized in that: In the engine typical state duration determination module, the engine states are classified and combined according to the impact of the engine on the exhaust duct heat and vibration environment, and a typical engine state is selected.

10. The aircraft engine exhaust duct thermal vibration load spectrum compilation system according to claim 9, characterized in that: In the engine typical state duration determination module, the engine typical states include idling state, rated power state, and take-off state.

11. The aircraft engine exhaust duct thermal vibration load spectrum compilation system according to claim 10, characterized in that: In the engine typical state-time spectrum construction module, the temperature load and vibration load of the exhaust duct under different typical engine states are determined during the design phase by referring to the vibration environment test results and temperature spectra of similar aircraft.

12. The aircraft engine exhaust duct thermal vibration load spectrum compilation system according to claim 11, characterized in that: In the engine typical state-time spectrum construction module, the vibration load is given in the form of pulsating pressure or sound pressure in the exhaust duct, and the temperature load is given in the form of temperature distribution or temperature peak of the inner wall of the exhaust duct.

Images