Titanium hybrid material double-layer damage safety lug reliability calculation and analysis method

Abstract

The invention belongs to the field of aircraft structure design and strength analysis, and particularly relates to a titanium hybrid material double-layer damage safety lug reliability calculation and analysis method, a lug comprises a lug 1 and a lug 2, and the method comprises the steps that the reliable work condition of a lug structure is divided into two states of no failure of two layers of lugs and failure of any one layer of lugs; calculating the reliability of the two layers of ear pieces in the non-failure state; carrying out load distribution through a stiffness distribution method, and establishing a load distribution function and a life conversion function; calculating the failure reliability of any layer of lug; and finally, the reliability of the lug structure is the sum of the occurrence probabilities of the two states.

Description

Technical Field

[0001] This application belongs to the field of aircraft structural design and strength analysis, and specifically relates to a method for calculating and analyzing the reliability of a double-layered damaged safety lug made of titanium hybrid material. Background Technology

[0002] Aircraft hinge structures are critical mechanical devices that connect movable components such as wings, flaps, and ailerons to the fuselage or fixed structures. These structures withstand complex loads and stress distributions during flight, including aerodynamic loads, inertial loads, and thermal stresses caused by temperature changes. Because the reliability of aircraft hinge structures directly affects the safety and service life of the aircraft, extremely high requirements are placed on their design and analysis.

[0003] In recent years, with the continuous improvement of aircraft performance, the requirements for hinge structures have become increasingly stringent. Traditional single-layer lug designs may not meet the failure safety requirements under certain extreme conditions, thus multi-layer lug failure safety structures have gradually become a research hotspot. This structure, through the use of multi-layer redundancy design, can maintain the integrity and safety of the overall structure even if a single lug fails, thereby significantly improving the safety of the aircraft.

[0004] Multi-path lug structures are load-sharing parallel systems involving load transfer and sharing, making their reliability analysis more complex than that of traditional parallel systems. Experiments have shown that the lifespan of a single lug follows a log-normal distribution, but the lifespan distribution of a multi-path lug structure, composed of multiple lugs connected by bolts or rivets, is difficult to determine. This is primarily because the failure of a single lug leads to a redistribution of the load on the surviving lugs and changes in the structure's lifespan distribution parameters, indicating a correlation between the failures of different lug layers in a multi-path lug structure; they are not independent during operation. Therefore, traditional parallel system reliability models are not applicable to the reliability analysis of multi-path lug structures. Developing a reliability calculation and analysis method for a three-layer damaged safety lug made of titanium hybrid material is of great significance for accurate and rapid calculation of aircraft reliability. Summary of the Invention

[0005] To address the aforementioned issues, this application provides a method for calculating and analyzing the reliability of a double-layered, damaged safety lug made of titanium hybrid material. The lug includes lug 1 and lug 2. The method includes:

[0006] The reliable operation of the ear plate structure is divided into two states: neither of the two ear plates has failed, and either one ear plate has failed.

[0007] Obtain the two earpieces in the time intervals. The distribution parameters within are , μ1 is the average value of the lifespan data obtained from the earpiece 1 test, σ1 is the standard deviation of the earpiece 1 lifespan data, μ2 is the average value of the lifespan data obtained from the earpiece 2 test, and σ2 is the standard deviation of the earpiece 2 lifespan data; all are obtained through experimental or simulation calculations.

[0008] Calculate the reliability of the condition where neither of the two ear plates has failed;

[0009] Load distribution is performed using the stiffness distribution method, and after establishing the load distribution function and life reduction function, the failure reliability of any layer of lugs is calculated.

[0010] The final reliability of the ear plate structure is the sum of the probabilities of the two states occurring.

[0011] Preferably, the reliability formula for the state where neither of the two ear pieces has failed is:

[0012] ;

[0013] t represents all possible time points where failure may occur, and e is a natural constant.

[0014] Preferably, within the time interval Any inner layer of earpiece at any time If a failure occurs, it will occur within the time interval. The distribution parameters of the inner double-layer ear pieces are as follows: , ;

[0015] Earpiece 2 in time interval The events that caused the failure are as follows: Its probability of occurrence is:

[0016] ;

[0017] Earpiece 2 in time interval The distribution parameters within are In the time interval The internal distributed parameter becomes ;

[0018] Earpiece 2 in time interval Working life within , for respectively at the distribution parameter of Working under the conditions until time V2 is the life reduction parameter of ear piece 2 after calculation using the load distribution function and life reduction function;

[0019] Let ear piece 1 be in any number of Sub-intervals Failure is an event Then the event A complete event group is formed; events The probability of occurrence is

[0020]

[0021] In the earpiece 1 failure event Given that this has already happened, the probability that earpiece 2 is reliable is:

[0022]

[0023] According to the law of total probability, we get

[0024]

[0025] Therefore, in the event of earplate 1 failure, the reliability of the redundant monoauricular structure is:

[0026]

[0027] Similarly, it can be deduced that in the case of earpiece 2 failure, the reliability of the redundancy earpiece structure is: ;

[0028] Therefore, the reliability of the redundancy ear structure is as follows: (This can be deduced from the information provided.)

[0029] .

[0030] Preferably, the load distribution function is:

[0031] ;

[0032] g i Let P be the load on the i-th lug, P be the tensile load shared by the lug, E be the elastic modulus of the lug, S be the cross-sectional area of ​​the lug, and l be the length of the lug. denoted as the thickness of the ear piece; n is the material crack propagation parameter; subscripts i and j represent the i-th and j-th ear pieces, respectively.

[0033] Preferably, the lifetime reduction function is:

[0034] ;

[0035] Preferably, ear piece 1 is made of aluminum and ear piece 2 is made of titanium.

[0036] The beneficial effects of this application are as follows: the failure of a single-layer lug leads to a redistribution of the load on the surviving lugs, and also causes changes in the life distribution parameters of the structure. This indicates that the failures of each layer of lugs in a multi-path load-transmission structure are correlated and not independent during operation. Traditional parallel system reliability models are not applicable to the reliability analysis of multi-path load-transmission lug structures. The reliability calculation method of this invention effectively solves this problem through the invented load distribution method, life equivalent calculation method, and reliability calculation method. Attached Figure Description

[0037] Figure 1 It is a two-layer aluminum-titanium hybrid safety ear plate structure. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are only some, not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings. Figure 1 To address the aforementioned issues, this application provides a method for calculating and analyzing the reliability of a double-layered, damaged safety lug made of titanium hybrid material. The lug includes lug 1 and lug 2. The method includes:

[0039] The reliable operation of the ear plate structure is divided into two states: neither of the two ear plates has failed, and either one ear plate has failed.

[0040] Obtain the two earpieces in the time intervals. The distribution parameters within are , μ1 is the average value of the lifespan data obtained from ear piece 1 test, σ1 is the standard deviation of the lifespan data of ear piece 1, μ2 is the average value of the lifespan data obtained from ear piece 2 test, and σ2 is the standard deviation of the lifespan data of ear piece 2.

[0041] Calculate the reliability of the condition where neither of the two ear plates has failed;

[0042] Load distribution is performed using the stiffness distribution method, and after establishing the load distribution function and life reduction function, the failure reliability of any layer of lugs is calculated.

[0043] The final reliability of the ear plate structure is the sum of the probabilities of the two states occurring.

[0044] (1) Neither of the two ear pieces failed.

[0045] Assuming within the time interval Inside, the two layers of ear pieces are respectively located at the distribution parameters of , Under the condition of operation, it can be seen from the formula that the reliability of the redundant double-ear structure under this condition is:

[0046]

[0047] (2) Failure of any layer of earpiece

[0048] Assuming within the time interval Any inner layer of earpiece at any time If a failure occurs, it will occur within the time interval. The distribution parameters of the inner double-layer ear pieces are as follows: , Earpiece 2 within the time interval The events that caused the failure are as follows: From the formula, we can see that its probability of occurrence is

[0049]

[0050] Earpiece 2 in time interval The distribution parameters within are In the time interval The internal distributed parameter becomes Meanwhile, the load distribution function and lifetime reduction function are:

[0051]

[0052]

[0053] Therefore, earpiece 2 in the time interval Working life within Based on the above formula, it can be seen as respectively at the distribution parameter being Working under the conditions until time Let ear piece 1 be in any position. Sub-intervals Failure is an event Then the event This constitutes a complete event group. Events The probability of occurrence is

[0054]

[0055] When earpiece 1 fails (i.e., event) Given that this has already occurred, the probability that earpiece 2 is reliable is:

[0056]

[0057] According to the law of total probability, we get

[0058]

[0059] Therefore, in the event of earplate 1 failure, the reliability of the redundant monoauricular structure is:

[0060]

[0061] Similarly, it can be deduced that in the case of ear piece 2 failure, the reliability of the redundancy ear piece structure is: Therefore, it can be concluded that, in the event of failure of one earpiece, the reliability of the redundancy earpiece structure is...

[0062] .

[0063] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for calculating and analyzing the reliability of a double-layered safety ear piece made of titanium hybrid material in case of failure, wherein the ear piece comprises ear piece 1 and ear piece 2, characterized in that, The method includes: The reliable operation of the ear plate structure is divided into two states: neither of the two ear plates has failed, and either one ear plate has failed. Obtain the two earpieces in the time intervals. The distribution parameters within are , μ1 is the average value of the lifespan data obtained from the earpiece 1 test, σ1 is the standard deviation of the earpiece 1 lifespan data, μ2 is the average value of the lifespan data obtained from the earpiece 2 test, and σ2 is the standard deviation of the earpiece 2 lifespan data; all are obtained through experimental or simulation calculations. Calculate the reliability of the condition where neither of the two ear plates has failed; Load distribution is performed using the stiffness distribution method, and after establishing the load distribution function and life reduction function, the failure reliability of any layer of lugs is calculated. The final reliability of the ear plate structure is the sum of the probabilities of the two states occurring.

2. The reliability calculation and analysis method for double-layer damaged safety lugs of titanium hybrid materials as described in claim 1, characterized in that, The reliability formula for a state where neither of the two lugs has failed is: ； t represents all possible time points where failure may occur, and e is a natural constant.

3. The reliability calculation and analysis method for double-layer damaged safety lugs of titanium hybrid materials as described in claim 1, characterized in that, In the time interval Any inner layer of earpiece at any time If a failure occurs, it will occur within the time interval. The distribution parameters of the inner double-layer ear pieces are as follows: , ; Earpiece 2 in time interval The events that caused the failure are as follows: Its probability of occurrence is: ； Earpiece 2 in time interval The distribution parameters within are In the time interval The internal distributed parameter becomes ; Earpiece 2 in time interval Working life within , for respectively at the distribution parameter of Working under the conditions until time V2 is the life reduction parameter of ear piece 2 after calculation using the load distribution function and life reduction function; Let ear piece 1 be in any number of Sub-intervals Failure is an event Then the event A complete event group is formed; events The probability of occurrence is 。 4. In the earpiece 1 failure event Given that this has already happened, the probability that earpiece 2 is reliable is: 。 5. According to the law of total probability, we get 。 6. Therefore, in the event of earpiece 1 failure, the reliability of the redundant monoauricular structure is: 。 7. Similarly, it can be deduced that in the case of ear piece 2 failure, the reliability of the redundancy ear piece structure is: ; Therefore, the reliability of the redundancy ear structure is as follows: (This can be deduced from the information provided.) 。 8. The reliability calculation and analysis method for a three-layer damaged safety lug made of titanium hybrid material as described in claim 3, characterized in that, The load distribution function is: ； g i Let P be the load on the i-th lug, P be the tensile load shared by the lug, E be the elastic modulus of the lug, S be the cross-sectional area of ​​the lug, and l be the length of the lug. denoted as the thickness of the ear piece; n is the material crack propagation parameter; subscripts i and j represent the i-th and j-th ear pieces, respectively.

9. The reliability calculation and analysis method for a three-layer damaged safety lug made of titanium hybrid material as described in claim 4, characterized in that, The lifespan reduction function is: 。 10. The reliability calculation and analysis method for a three-layer damaged safety lug made of titanium hybrid material as described in claim 1, characterized in that, Earpiece 1 is made of aluminum, and earpiece 2 is made of titanium.

Images