A high-temperature static test design method and system for rear-bearing casing

Abstract

The present invention belongs to the field of aviation engines, relates to a static test design technology for aft-bearing casings, and provides a high-temperature static test design method and system for aft-bearing casings, the method comprising: determining the load analysis conditions and assessment locations of the aft-bearing casings within the engine envelope, the load analysis conditions comprising the ultimate load analysis conditions and the limiting load analysis conditions; determining the external loads under the load analysis conditions; constructing a static test piece for the aft-bearing casings; equivalencing the force loads in the external loads and the basic loads, respectively constructing the temperature fields for the ultimate load analysis conditions and the limiting load analysis conditions; allocating equivalent loads, first conducting a limiting load test, and then conducting an ultimate load test. The method of the present invention can meet the assessment requirements for static tests of aft-bearing casings, and more comprehensively guarantee the safety and reliability of aft-bearing casings in high-temperature environments.

Description

Technical Field

[0001] The present invention belongs to the field of aero-engines, relates to a static test design technology for a rear-bearing casing, and in particular to a high-temperature static test design method and system for a rear-bearing casing. Background Art

[0002] The rear casing is a critical load-bearing frame in aircraft engines, primarily bearing the thrust and vibration loads of the engine, directly impacting its performance, lifespan, and reliability. According to the GJB241A-2010 standard, "General Requirements for Reliability of Electronic Equipment," static testing is required to ensure the reliability of the rear casing.

[0003] At present, the traditional method is to conduct static tests at room temperature, and use the temperature correction coefficient to amplify the load that contributes more during the test. If there are multiple test parts, the maximum value of the multiple temperature correction coefficients needs to be selected to amplify the load. However, with the continuous improvement of engine performance indicators, the temperature gradient of the rear bearing casing has increased significantly, and the influence of thermal stress has exceeded 80%. It is no longer possible to simulate dangerous parts by conducting room temperature tests. Therefore, due to the influence of temperature, the most dangerous external load combination screened by the stress value of the test part is no longer accurate. In addition, the failure mechanism caused by heat is more complicated. At present, the dangerous parts caused by thermal stress in the industry are usually evaluated by separately designed tests.

[0004] In view of this, it is imperative to carry out static tests on the rear-bearing casing under high-temperature working conditions. Summary of the Invention

[0005] In order to solve the technical problem that the rear bearing casing cannot reach the dangerous parts through room temperature static test under large temperature gradient, the present invention discloses a high temperature static test design method for the rear bearing casing, which includes the following steps:

[0006] S1. Obtaining load analysis conditions and assessment locations within the rear bearing casing within the engine envelope based on the ultimate tensile strength and ultimate yield strength, wherein the load analysis conditions include ultimate load analysis conditions and limiting load analysis conditions;

[0007] S2. determining the external load under the load analysis condition by a stress component matrix algorithm;

[0008] S3. Install multiple first actuators on the auxiliary mounting section of the rear bearing casing, install multiple second actuators on the fulcrum adapter casing, set a temperature field control device near the bearing support of the rear bearing casing, and construct a static test piece for the rear bearing casing;

[0009] S4. Equilibrating the external load and the force load in the basic load according to the force load equivalence logic, respectively, to construct a temperature field for an extreme load analysis condition and a temperature field for a limit load analysis condition;

[0010] S5. Distribute the equivalent load to the first actuator and the second actuator, first perform a limited load test using the temperature field of the limited load analysis working condition and the equivalent load of the limited load analysis working condition, and then perform a limit load test using the temperature field of the limit load analysis working condition and the equivalent load of the limit load analysis working condition.

[0011] Furthermore, in the above step S1, based on the tensile strength limit and the yield strength limit, the load analysis working conditions and assessment positions of the rear bearing casing within the engine envelope are obtained, including:

[0012] S11. Obtaining a stress field at each operating state within the engine envelope using a simulation method, and obtaining an equivalent stress at each position on the rear bearing casing based on the stress field;

[0013] S12. Calculate the yield strength reserve at each position in each working state based on the equivalent stress and the yield strength limit, and use the working state with the smallest yield strength reserve among all the working states as the limiting load analysis condition;

[0014] S13. Calculate the ultimate strength reserve at each position in each working state based on the equivalent stress and the tensile strength limit, and use the working state with the smallest ultimate strength reserve among all the working states as the ultimate load analysis condition;

[0015] S14. Extract all the positions where the yield strength reserve is within the yield strength threshold range under the limit load analysis working condition, extract all the positions where the ultimate strength reserve is within the ultimate strength threshold range under the limit load analysis working condition, and use all the extracted positions as assessment positions.

[0016] Furthermore, in the above step S2, the external load under the load analysis condition is determined by a stress component matrix algorithm, including:

[0017] S21. Obtain multiple sets of maneuvering overload combination coefficients representing external loads borne during maneuvering flight;

[0018] S22. For each set of maneuvering overload combination coefficients, calculate the product of the second stress result under each unit maneuvering overload and the corresponding maneuvering overload coefficient, and sum all the products to obtain the external load stress;

[0019] S23. Calculate the material strength reserve under each set of the maneuverable overload combination coefficients based on the material strength limit and the external load equivalent stress of the external load stress, and use the maneuverable overload combination coefficient with the smallest material strength reserve as the external load, wherein the material strength limit includes the tensile strength limit and the yield strength limit, and the material strength reserve includes the yield strength reserve and the ultimate strength reserve.

[0020] Furthermore, in the above step S4, the force loads in the external load and the basic load are respectively equivalent according to the force load equivalent logic, including:

[0021] S41. Obtain the force load from the basic load that cannot be directly applied during the high-temperature static test;

[0022] S42, respectively calculating the equivalent stress of the assessment part generated by the external load and each force load at the assessment part, and obtaining the external equivalent force load according to the force load equivalent logic whose deviation from the equivalent stress of each assessment part is within a set deviation range.

[0023] Furthermore, the above step S4 further includes:

[0024] S43. Correct each of the external equivalent force loads using the temperature coefficient to obtain a final external equivalent force load.

[0025] Furthermore, the above step S4 further includes:

[0026] S40 , performing sensitivity analysis on each of the force loads to obtain an influencing factor, eliminating the force loads whose influencing factors are less than a threshold, and obtaining a final force load, wherein the final force load includes a pressure load and a torque.

[0027] Furthermore, in the above step S40, a sensitivity analysis is performed on each of the force loads to obtain an influencing factor, including:

[0028] S401, for the load analysis working condition, unidirectionally load the temperature load and each force load in the basic load to the rear bearing casing, and obtain the first stress result and the stress result of the assessment part under the temperature load and each force load by a simulation method;

[0029] S402, respectively calculating the product of the temperature load and the first stress result under each force load and its corresponding safety factor, summing all the products and performing stress equivalence to obtain a basic load equivalent stress, and calculating the sum of the basic load equivalent stress and the external load equivalent stress;

[0030] S403, calculating the ratio of the stress result of the assessment part to the sum under each force load, and obtaining the influence factor of the force load.

[0031] Furthermore, in the above step S4, respectively constructing the temperature field of the extreme load analysis working condition and the temperature field of the limit load analysis working condition includes:

[0032] S44. For the limited load analysis working condition, the temperature field control device generates a temperature field identical to the engine state as the limited load analysis working condition temperature field;

[0033] S45. For the extreme load analysis condition, the temperature gradient under the extreme load analysis condition is calculated through the static test of the casing and the tensile strength, linear expansion coefficient, elastic modulus and temperature gradient of the casing during engine service. The temperature field of the extreme load analysis condition is constructed through the temperature field control device and the temperature gradient.

[0034] An embodiment of the present invention also provides a high-temperature static test design system for a rear-bearing casing, including a load analysis condition and assessment location determination module, an external load acquisition module, a rear-bearing casing static test piece, an equivalent module and a temperature field construction module.

[0035] The load analysis condition and assessment location determination module is used to obtain the load analysis condition and assessment location of the rear bearing casing within the engine envelope based on the tensile strength limit and the yield strength limit. The load analysis condition includes an extreme load analysis condition and a limit load analysis condition.

[0036] The external load acquisition module is used to determine the external load under the load analysis working condition through a stress component matrix algorithm;

[0037] The static test piece of the rear bearing casing includes a plurality of first actuators arranged on the auxiliary mounting section of the rear bearing casing, a plurality of second actuators arranged on the fulcrum adapter casing, and a temperature field control device arranged near the bearing support position of the rear bearing casing;

[0038] The equivalent module is used to respectively make the force loads in the external load and the basic load equivalent according to the force load equivalent logic;

[0039] The temperature field construction module is used to respectively construct the temperature field of the extreme load analysis working condition and the temperature field of the limit load analysis working condition.

[0040] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0041] The method of the present invention can solve the problem that the rear bearing casing with a large temperature gradient cannot represent the actual service conditions under room temperature static testing, ensure that the failure position and failure mode of the static test piece of the rear bearing casing are the same as those of the engine rear bearing casing, and meet the engineering safety and reliability requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0043] Figure 1 Flowchart of the design method for high temperature static test of rear bearing casing;

[0044] Figure 2 This is a schematic diagram of the static test piece of the rear-bearing casing;

[0045] Figure 3 This is a schematic diagram of the actuator on the static test piece of the rear-bearing casing;

[0046] Figure 4 Schematic diagram of the temperature field control device on the static test piece of the rear-bearing casing. DETAILED DESCRIPTION

[0047] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0048] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features of the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0049] The embodiment of the present invention discloses a method for designing a high temperature static test of a rear bearing casing, see Figure 1 As shown, the method includes the following steps:

[0050] S1. Obtaining load analysis conditions and assessment locations within the rear bearing casing within the engine envelope based on the ultimate tensile strength and ultimate yield strength, wherein the load analysis conditions include ultimate load analysis conditions and limiting load analysis conditions;

[0051] S2. determining the external load under the load analysis condition by a stress component matrix algorithm;

[0052] S3. Install multiple first actuators on the auxiliary mounting section of the rear bearing casing, install multiple second actuators on the fulcrum adapter casing, set a temperature field control device near the bearing support of the rear bearing casing, and construct a static test piece for the rear bearing casing;

[0053] S4. Equilibrating the external load and the force load in the basic load according to the force load equivalence logic, respectively, to construct a temperature field for an extreme load analysis condition and a temperature field for a limit load analysis condition;

[0054] S5. Distribute the equivalent load to the first actuator and the second actuator, first perform a limited load test using the temperature field of the limited load analysis working condition and the equivalent load of the limited load analysis working condition, and then perform a limit load test using the temperature field of the limit load analysis working condition and the equivalent load of the limit load analysis working condition.

[0055] Furthermore, in the above step S1, based on the tensile strength limit and the yield strength limit, the load analysis working conditions and assessment positions of the rear bearing casing within the engine envelope are obtained, including:

[0056] S11. Obtain a stress field for each operating state within the engine envelope using a simulation method, and obtain an equivalent stress at each location on the rear bearing casing based on the stress field. Operating states within the engine envelope typically include idle, low-load, high-load, maximum power, maximum torque, engine protection, and extreme operating conditions.

[0057] S12. Calculate the yield strength reserve at each position in each working state based on the equivalent stress and the yield strength limit, and use the working state with the smallest yield strength reserve among all the working states as the limiting load analysis condition.

[0058] S13. Calculate the ultimate strength reserve at each position in each working state based on the equivalent stress and the tensile strength limit, and take the working state with the smallest ultimate strength reserve among all the working states as the ultimate load analysis condition.

[0059] The yield strength reserve and ultimate strength reserve at each position in each working state can be calculated using the following formulas (1) and (2):

[0060] ...Formula (1);

[0061] ... Formula (2);

[0062] in, is the yield strength limit of the material, is the equivalent stress, is the yield strength reserve; is the ultimate tensile strength of the material, Reserved for ultimate strength.

[0063] When determining the analysis condition, the working state with the minimum yield strength reserve / ultimate strength reserve is used as the limiting load analysis condition / ultimate load analysis condition.

[0064] S14. Extract all the positions where the yield strength reserve is within the yield strength threshold range under the limit load analysis working condition, extract all the positions where the ultimate strength reserve is within the ultimate strength threshold range under the limit load analysis working condition, and use all the extracted positions as assessment positions.

[0065] During specific implementation, the yield strength threshold range / ultimate strength threshold range can be set to 1~2 times the yield strength reserve / ultimate strength reserve according to user needs. As long as the positions within this range are assessment parts for high-temperature static stress tests, such as the connection positions between the support pillars on the rear bearing receiver and the inner and outer receivers, the edges of the mounting holes, the vent holes, etc. are all assessment areas.

[0066] Furthermore, in the above step S2, since the limiting load and the ultimate load need to take into account the external load, and different external loads can be combined to form hundreds of overload combinations (which are represented by the maneuvering overload combination coefficient), in the present invention, the high-temperature static stress test only needs to be performed under the most dangerous external load combination. Therefore, the external load under the load analysis condition is determined by the stress component matrix algorithm, including:

[0067] S21. Obtain multiple sets of maneuvering overload combination coefficients that characterize the external loads borne during maneuvering flight. The maneuvering overload combination coefficients can be obtained from the aircraft flight requirements and can be expressed by the following formula (3):

[0068] .......Formula (3), where, ~ There are 7 different types of maneuvering overload coefficients in each set of maneuvering overload combination coefficients, which can be extracted from the design requirements of maneuvering flight.

[0069] S22. For each set of maneuvering overload combination coefficients, calculate the product of the second stress result under each unit maneuvering overload and its corresponding maneuvering overload coefficient, and sum all the products to obtain the external load stress.

[0070] A certain external load stress component in the external load stress can be expressed by the following formula (4):

[0071] .......Formula (4), where, It represents the sum of the jth stress component of a certain set of maneuvering overload combination coefficients in the i-th node of the rear bearing casing, that is, the external load stress component; is the ath unit maneuvering overload coefficient in the maneuvering overload combination coefficient; It represents the jth stress component in the i-th node of the rear bearing casing at the a-th unit maneuvering overload in a set of maneuvering overload combination coefficients.

[0072] Generally speaking, each node has 6 stress components, corresponding to 6 external load stress components. When used in the following step S23, the 6 external load stress components of each node need to be equivalent to obtain the external load stress of the node.

[0073] S23. Calculate the material strength reserve under each set of the maneuverable overload combination coefficients based on the material strength limit and the external load equivalent stress of the external load stress, and use the maneuverable overload combination coefficient with the smallest material strength reserve as the external load, wherein the material strength limit includes the tensile strength limit and the yield strength limit, and the material strength reserve includes the yield strength reserve and the ultimate strength reserve.

[0074] When determining the external load, the strength reserve of the casing test part is compared under different groups of maneuvering overload combination coefficient conditions, and the group of maneuvering overload combination coefficients with the smallest reserve is selected as the external load for the casing static test.

[0075] Furthermore, in the above step S3, if Figure 2 and Figure 3 As shown, a static test specimen for the rear-loaded casing is designed, comprising the test specimen (the rear-loaded casing) and the adapter casing. The test specimen primarily comprises the rear-loaded outer casing 1, the load-bearing struts 2, and the rear-loaded inner casing 3; the adapter casing primarily comprises the outer-casing adapter casing 5 and the pivot adapter casing 6. The front end 13 of the outer-casing adapter casing is secured to the tester; actuators (the first, second, third, and fourth actuators 9, 10, 11, and 12) are installed in the auxiliary mounting section 4 to apply the load; and loads (the fifth and sixth actuators 7, 8) are applied to the center hole 14 of the pivot adapter casing 6.

[0076] See also Figure 4As shown, the temperature field control device primarily consists of a quartz lamp array 21 (one for each support column), a heat shield 22, cooling gas 24, a cooling annular housing 23, and thermocouples. To achieve a gradient temperature field, the support columns are heated by thermal radiation from the quartz lamp array 21 within the cavity formed by the heat shield 22 until the average temperature of the radial section where the support plate's highest temperature lies reaches the target temperature. A cooling annular housing 23 is added to the outer side of the outer housing, and cooling gas 24 is introduced into the cavity between the inner and outer housings until the lowest temperature of the inner and outer housings reaches the target temperature. The temperature of the test area is controlled by heat conduction, creating a large temperature gradient. Thermocouples are placed to monitor temperature at the radial section where the support plate's highest temperature lies, at the lowest temperature region of the inner and outer housings adjacent to the support plate, and at the test location. The power and size of the quartz lamps, the distance between the lamps and the test specimen's support plate, and the temperature and flow rate of the cooling gas are adjusted to control the temperature at different locations of the test specimen. This achieves a large gradient temperature field in the rear support housing, ensuring that the test specimen's temperature conforms to the designed temperature field distribution.

[0077] Furthermore, in the above step S4, the force loads in the external load and the basic load are respectively equivalent according to the force load equivalent logic, including:

[0078] S40 , performing sensitivity analysis on each of the force loads to obtain an influencing factor, eliminating the force loads whose influencing factors are less than a threshold, and obtaining a final force load, wherein the final force load includes a pressure load and a torque.

[0079] S41. Obtain the force load from the basic load that cannot be directly applied during the high-temperature static test;

[0080] S42, respectively calculating the equivalent stress of the assessment part generated by the external load and each force load at the assessment part, and obtaining the external equivalent force load according to the force load equivalent logic whose deviation from the equivalent stress of each assessment part is within a set deviation range.

[0081] Furthermore, the above step S4 further includes:

[0082] S43. Correct each of the external equivalent force loads using the temperature coefficient to obtain a final external equivalent force load.

[0083] During the implementation, because the temperature field applied during the static test of the casing is not completely consistent with the temperature field it is subjected to when in service in the engine, it is necessary to perform temperature correction on the external equivalent force loads determined in S42. The loads implemented during the actual test need to be multiplied by the corresponding temperature coefficients (including To limit the load temperature coefficient, The temperature coefficient is calculated as follows:

[0084] ........(Formula 13);

[0085] ..........(Formula 14);

[0086] Where, and are the material strength of the test part temperature under the limiting load and ultimate load in the box static test (the material strength under the limiting load is the yield strength, and the material strength under the ultimate load is the tensile strength); and They are the material strength of the casing at the temperature of the test parts under the limiting load and ultimate load during engine service.

[0087] Through correction, the strength check is completed to ensure that the reserve of the test part is basically consistent in the static test state of the casing and the service state of the engine, the reserve coefficient of the test state is not lower than that of the engine state, and at the same time ensure that the accompanying test piece will not be damaged before the test piece.

[0088] Furthermore, in the above step S40, a sensitivity analysis is performed on each of the force loads to obtain an influencing factor, including:

[0089] S401. For the load analysis condition, unidirectionally load the temperature load and each force load in the basic load onto the rear bearing casing, and obtain the first stress result and the stress result of the assessment part under the temperature load and each force load by a simulation method.

[0090] During implementation, the load types and their corresponding safety factors are shown in Table 1 below:

[0091] Table 1: Load types and their corresponding safety factors

[0092]

[0093] S402. Calculate the product of the temperature load and the first stress result under each force load and the corresponding safety factor respectively, sum all the products and perform stress equivalence to obtain a basic load equivalent stress, and calculate the sum of the basic load equivalent stress and the external load equivalent stress.

[0094] In specific implementation, the jth stress component in the i-th node in the basic load equivalent stress can be expressed by the following formula (5):

[0095] ...................Formula (5), where is the jth stress component in the i-th node in the basic load equivalent stress, is the stress result of the jth stress component in the i-th node of the rear bearing casing, is the safety factor. Usually each node has 6 stress components, so the basic load equivalent stress is obtained by equivalently calculating the 6 stress components.

[0096] The sum of the equivalent stress of basic load and the equivalent stress of external load It can be expressed by the following formula (6):

[0097] .....................................Equation (6).

[0098] S403, calculating the ratio of the stress result of the assessment part to the sum under each force load, and obtaining the influence factor of the force load.

[0099] During implementation, the equivalent stress of the i-th node in the stress results of the assessment part under a certain force load can be expressed as , the yield strength reserve / ultimate strength reserve calculated in step S23 is used to calculate the impact factor using the following formula (7): :

[0100] .....................(Formula 7);

[0101] is the influence factor of a certain force load, if If the load is less than a threshold value (such as 5%), the force load is an insensitive load; If it is greater than 5%, the force load is a sensitive load.

[0102] Furthermore, in the above step S42, the equivalent method of pressure load, torque and external load is:

[0103] Pressure load equivalence: Due to the complex structure and load of the rear bearing casing, the pressure load applied to the rear bearing casing is very complex. It cannot be applied directly and needs to be converted and applied through the actuator. Specifically, the axial force generated by the pressure load of each cavity is simplified to the axial load at the center hole position of the fulcrum adapter casing 6 through load equivalence. The load equivalence requirement is: use the axial load after equivalent replacement to carry out single load analysis, and the equivalent stress value of the assessment part , which is equivalent to the equivalent stress of the test part under the pressure load in the sensitive load analysis Compare, if the deviation If the deviation is within 1%, then the solution of using the pressure load as the equivalent axial load is reasonable. Otherwise, adjust the axial load value until it meets the requirements. It can be calculated by the following formula (8):

[0104] (Equation 8).

[0105] Torque Equivalence: Torque originates from the auxiliary mounting section or rear receiver, and is converted into a force load in the opposite direction. The load equivalence requirement is that the deviation between the equivalent force load and the equivalent stress generated by the original torque load at the receiver test site must be within 1%.

[0106] External Load Equivalence: External loads are primarily transmitted through the fulcrum adapter housing 6 and the auxiliary mounting section 4. The auxiliary mounting section has multiple loading points around it. To minimize excessive bending moments, the load is typically evenly distributed across symmetrical loading points. The specific number of loading points is determined by the number of actuators and the strength of the loading points. The load equivalence requirement is that the deviation between the equivalent effective load and the equivalent stress generated by the original external load at the test location on the housing must be within 1%.

[0107] Furthermore, in the above step S4, respectively constructing the temperature field of the extreme load analysis working condition and the temperature field of the limit load analysis working condition includes:

[0108] S44. For the limited load analysis working condition, the temperature field control device generates a temperature field identical to the engine state as the limited load analysis working condition temperature field.

[0109] During implementation, the temperature field of the limited load test should be completely consistent with the engine's state. If this consistency is not possible due to limitations in the test equipment's maximum heating temperature and temperature field control capabilities, an equivalent treatment can be achieved by constructing a temperature field with the same reserve. The equivalent temperature field should ensure consistency in the average temperature of the radial section where the support plate reaches its highest temperature, consistency in the lowest temperatures of the inner and outer casings, consistency in the test area, and consistency in the thermal load reserve induced by the temperature field.

[0110] S45. For the extreme load analysis condition, the temperature gradient under the extreme load analysis condition is calculated through the static test of the casing and the tensile strength, linear expansion coefficient, elastic modulus and temperature gradient of the casing during engine service. The temperature field of the extreme load analysis condition is constructed through the temperature field control device and the temperature gradient.

[0111] During implementation, the ultimate load needs to consider 1.5 times the thermal load, and the temperature field under the ultimate load needs to be analyzed, especially the temperature gradient that causes the thermal load. Designed to ensure 1.5 times the heat load reserve The specific conversion formula is as follows:

[0112] ............(Formula 9);

[0113] ............(Formula 10);

[0114] ............(Formula 11);

[0115] .....(Formula 12);

[0116] Where: 、 、 、 They are the material tensile strength, linear expansion coefficient, elastic modulus, and casing temperature gradient of the equivalent temperature field of the ultimate load of the casing static test; 、 、 、 are the material tensile strength, linear expansion coefficient, elastic modulus, and casing temperature gradient of the casing under the extreme load temperature field during engine service. From the above formulas (9) to (12), it can be seen that the maximum temperature under the extreme load is determined according to the maximum heating capacity of the equipment, and the calculated temperature gradient is The extreme load temperature field can be constructed.

[0117] Furthermore, in the above step S5,

[0118] First, each of the external equivalent force loads is evenly distributed to the first actuator and / or the second actuator according to the external load and the position of each force load on the rear bearing casing;

[0119] Secondly, load application: After the specimen is preheated to the test temperature, loading begins. The test load is applied in stages, with each stage increment not exceeding 20% ​​of the maximum test load. Load increments can be reduced to 10%-5% before reaching the maximum load. The specimen temperature is monitored throughout the test, with temperature fluctuations within ±15°C. Various loads must be applied simultaneously and slowly, with coordinated synchronization. The maximum steady-state load accuracy for each test group is 0-+2%.

[0120] Finally, load holding and unloading: the load holding time after reaching the maximum load during the test is generally required to be 5 minutes, and the load holding time for other loading and unloading levels shall not be less than 1 minute.

[0121] The method of the present invention can solve the problem that the rear bearing casing with a large temperature gradient cannot represent the actual service conditions under room temperature static testing, ensure that the failure position and failure mode of the static test piece of the rear bearing casing are the same as those of the engine rear bearing casing, and meet the engineering safety and reliability requirements.

[0122] Based on the same inventive concept, an embodiment of the present invention further provides a rear-bearing casing high-temperature static test design system, as described in the following embodiments. Since the principle of solving the problem of the rear-bearing casing high-temperature static test design system is similar to that of the rear-bearing casing high-temperature static test design method, the implementation of the rear-bearing casing high-temperature static test design system can refer to the implementation of the rear-bearing casing high-temperature static test design method disclosed in the above embodiments, and the repeated parts will not be repeated. As used below, the term "unit" or "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and conceived.

[0123] The high-temperature static test design system for the rear-bearing casing disclosed in an embodiment of the present invention includes a load analysis condition and assessment location determination module, an external load acquisition module, a rear-bearing casing static test piece, an equivalent module and a temperature field construction module.

[0124] The load analysis condition and assessment location determination module is used to obtain the load analysis condition and assessment location of the rear bearing casing within the engine envelope based on the tensile strength limit and the yield strength limit. The load analysis condition includes an extreme load analysis condition and a limit load analysis condition.

[0125] The external load acquisition module is used to determine the external load under the load analysis working condition through a stress component matrix algorithm;

[0126] The static test piece of the rear bearing casing includes a plurality of first actuators arranged on the auxiliary mounting section of the rear bearing casing, a plurality of second actuators arranged on the fulcrum adapter casing, and a temperature field control device arranged near the bearing support position of the rear bearing casing;

[0127] The equivalent module is used to respectively make the force loads in the external load and the basic load equivalent according to the force load equivalent logic;

[0128] The temperature field construction module is used to respectively construct the temperature field of the extreme load analysis working condition and the temperature field of the limit load analysis working condition.

[0129] Obviously, those skilled in the art will understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations are possible in the embodiments of the present invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A high temperature static test design method for a rear bearing casing, characterized in that: include: Obtaining load analysis conditions and assessment locations of the rear bearing casing within the engine envelope based on the tensile strength limit and the yield strength limit, wherein the load analysis conditions include ultimate load analysis conditions and limiting load analysis conditions; determining the external load under the load analysis condition by a stress component matrix algorithm; A plurality of first actuators are installed on the auxiliary mounting section of the rear bearing casing, a plurality of second actuators are installed on the fulcrum adapter casing, a temperature field control device is set at the bearing support position near the rear bearing casing, and a static test piece of the rear bearing casing is constructed; According to the force load equivalence logic, the force loads in the external load and the basic load are respectively equivalent, and the temperature field of the extreme load analysis condition and the temperature field of the limit load analysis condition are respectively constructed, including: obtaining the force loads in the basic load that cannot be directly loaded during the high-temperature static test; respectively calculating the equivalent stress of the test part generated by the external load and each of the force loads at the test part, and obtaining the external equivalent force load according to the force load equivalence logic whose deviation from the equivalent stress of each of the test parts is within a set deviation range; The equivalent load is distributed to the first actuator cylinder and the second actuator cylinder, and a limited load test is first performed through the limited load analysis working condition temperature field and the equivalent load of the limited load analysis working condition, and then a limit load test is performed through the limit load analysis working condition temperature field and the equivalent load of the limit load analysis working condition.

2. The high temperature static test design method for the rear bearing casing according to claim 1 is characterized in that: Based on the tensile strength limit and yield strength limit, the load analysis conditions and assessment locations of the rear bearing casing within the engine envelope are obtained, including: Acquire the stress field of each working state within the engine envelope by a simulation method, and obtain the equivalent stress at each position on the rear bearing casing according to the stress field; Calculating the yield strength reserve at each position in each working state according to the equivalent stress and the yield strength limit, and using the working state with the smallest yield strength reserve among all the working states as the limiting load analysis condition; Calculating the ultimate strength reserve at each position in each working state according to the equivalent stress and the tensile strength limit, and taking the working state with the smallest ultimate strength reserve among all the working states as the ultimate load analysis condition; Extract all the positions where the yield strength reserve is within the yield strength threshold range under the limit load analysis condition, extract all the positions where the ultimate strength reserve is within the ultimate strength threshold range under the limit load analysis condition, and use all the extracted positions as assessment positions.

3. The high temperature static test design method for the rear bearing casing according to claim 1 is characterized in that: The external loads for the load analysis condition are determined using a stress component matrix algorithm, including: Obtain multiple sets of maneuvering overload combination coefficients representing the external loads borne during maneuvering flight; For each set of maneuvering overload combination coefficients, calculating the product of the second stress result under each unit maneuvering overload and the corresponding maneuvering overload coefficient, and summing all the products to obtain the external load stress; According to the material strength limit and the external load equivalent stress of the external load stress, the material strength reserve under each group of the maneuverable overload combination coefficients is calculated, and the maneuverable overload combination coefficient with the smallest material strength reserve is used as the external load, wherein the material strength limit includes the tensile strength limit and the yield strength limit, and the material strength reserve includes the yield strength reserve and the ultimate strength reserve.

4. The high temperature static test design method for the rear bearing casing according to claim 1 is characterized in that: Also includes: Each of the external equivalent force loads is corrected respectively by using the temperature coefficient to obtain a final external equivalent force load.

5. The high temperature static test design method for the rear bearing casing according to claim 1 is characterized in that: Also includes: A sensitivity analysis is performed on each of the force loads to obtain an influencing factor, and the force loads with an influencing factor less than a threshold are eliminated to obtain a final force load, wherein the final force load includes a pressure load and a torque.

6. The high temperature static test design method for the rear bearing casing according to claim 5 is characterized in that: A sensitivity analysis is performed on each of the force loads to obtain the influencing factors, including: For the load analysis condition, the temperature load and each force load in the basic load are unidirectionally applied to the rear bearing casing, and a first stress result and a stress result of the assessment part under the temperature load and each force load are obtained by a simulation method; Calculating the product of the first stress result under the temperature load and each force load and the corresponding safety factor respectively, summing all the products and performing stress equivalence to obtain a basic load equivalent stress, and calculating the sum of the basic load equivalent stress and the external load equivalent stress; The ratio of the stress result of the test part under each force load to the sum is calculated to obtain the influence factor of the force load.

7. The high temperature static test design method for the rear bearing casing according to claim 1 is characterized in that: Construct the temperature field of the extreme load analysis condition and the temperature field of the limit load analysis condition respectively, including: For the limited load analysis working condition, the temperature field control device generates a temperature field identical to the engine state as the limited load analysis working condition temperature field; For the extreme load analysis condition, the temperature gradient under the extreme load analysis condition is calculated through the static test of the casing and the tensile strength, linear expansion coefficient, elastic modulus and temperature gradient of the casing material during engine service. The temperature field of the extreme load analysis condition is constructed through the temperature field control device and the temperature gradient.

8. A high temperature static test design system for a rear bearing casing, characterized in that: include: a load analysis condition and assessment location determination module, which is used to obtain the load analysis condition and assessment location of the rear bearing casing within the engine envelope based on the tensile strength limit and the yield strength limit, wherein the load analysis condition includes an extreme load analysis condition and a limit load analysis condition; An external load acquisition module, configured to determine the external load under the load analysis condition by using a stress component matrix algorithm; A static test piece for a rear-bearing casing, comprising a plurality of first actuators disposed on an auxiliary mounting section of the rear-bearing casing, a plurality of second actuators disposed on a fulcrum adapter casing, and a temperature field control device disposed near a bearing support of the rear-bearing casing; An equivalent module, the equivalent module is used to respectively equate the external load and the force load in the basic load according to the force load equivalent logic, including: obtaining the force load in the basic load that cannot be directly loaded during the high-temperature static test; respectively calculating the test part equivalent stress generated by the external load and each of the force loads at the test part, and obtaining the external equivalent force load according to the force load equivalent logic whose deviation from the equivalent stress of each test part is within a set deviation range; A temperature field construction module is used to construct a temperature field for an extreme load analysis condition and a temperature field for a limit load analysis condition respectively.

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