Aviation electromechanical liquid product service life determination method based on performance model simulation

Abstract

The invention belongs to the technical field of reliability analysis of aviation products, and particularly relates to a method for determining the service life of an aviation mechanical-electrical-hydraulic product based on performance model simulation, which comprises the following steps: S1, collecting information of the aviation mechanical-electrical-hydraulic product, and completing failure mechanism analysis of the aviation mechanical-electrical-hydraulic product according to product failure mode, influence and criticality analysis; s2, determining a load profile of each lowest agreed level according to the one-dimensional performance control model of the aviation electromechanical hydraulic product, and carrying out stress analysis on the aviation electromechanical hydraulic product; s3, the durability index of the aviation electromechanical liquid product is analyzed through a linear cumulative damage method, and the wear-type failure time is obtained; and S4, determining a weak link of the aviation electromechanical hydraulic product according to the lowest agreed level with the shortest service life in the aviation electromechanical hydraulic product, and obtaining the service life of the aviation electromechanical hydraulic product. According to the method, through full-life periodic performance simulation, load information and boundary conditions of the lowest agreed level of the electromechanical hydraulic product are obtained, and stress analysis and loss type failure time calculation are achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of aviation product reliability analysis, and in particular relates to a method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation. Background Art

[0002] Aircraft mechanical products mainly include hydraulic and pneumatic equipment such as actuators, valves, pumps, valves, locks, etc., electromechanical equipment such as electromechanical actuators, generators, electric seats, and motion mechanisms such as locking mechanisms, control mechanisms, and retracting mechanisms. They are widely used in flight control, fuel, hydraulic, environmental control, landing gear and other key airborne systems that directly affect aircraft safety and missions. Among them, solenoid valves, servo actuators and other complex products involving multiple fields of electromechanical and hydraulic are the key to affecting the functions and reliability of each system.

[0003] At present, durability simulation tests are often carried out in the development stage of aviation products. Based on the generalized stress-strength and cumulative damage principles and computer technology, the load history experienced by the product, including working load and environmental load, is simulated on the digital prototype of the product, and then decomposed into the lowest agreed level unit of the product for stress analysis. The failure model is then used to calculate the wear-out failure time of each component. According to the principle of shortest time, the service life of the product, i.e. the first occurrence time of wear-out failure, is determined, so as to find out the weak links in the durability of the product and evaluate the durability level of the product.

[0004] Due to the diversity of loads and the complexity of working principles of aviation electromechanical and hydraulic products, the following problems exist in the current durability simulation, which are mainly reflected in the following aspects: electromechanical and hydraulic products involve complex loads, and it is difficult to accurately obtain the loads on components. In the durability simulation test of general aviation products, the lowest agreed level load needs to be decomposed from the product load, among which the loads of some components can be directly determined by the product design information, and the loads involving mechanism dynamics such as connecting rod movement speed, cam torque, etc. can be obtained through multi-body dynamics and rotor dynamics simulation analysis, while the loads of electromechanical and hydraulic multi-field complex products such as the electromagnetic force on the jet valve armature, the medium pressure load spectrum in the slide valve cavity, and the motor coil current are difficult to obtain, and rely on the experience of product designers to obtain values, resulting in reduced accuracy of stress analysis results and inaccurate wear-type failure time. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation. On the basis of fully analyzing the functional principles and load conditions of the products, a multi-domain performance model of electromechanical and hydraulic products is established. Through performance simulation throughout the life cycle, the load information and boundary conditions of each lowest agreed level are obtained, and then the lowest agreed level stress analysis and failure time calculation are carried out based on this. For more complex load conditions, the performance model is combined with the finite element analysis model, CFD simulation model or directly with the failure model at the lowest agreed level through an interface to carry out joint simulation, so as to realize stress analysis and wear-type failure time calculation under accurate load conditions, and finally improve the analysis accuracy of the service life and the confidence of the durability simulation results.

[0006] To achieve the above-mentioned purpose, the present invention discloses the following technical solution: a method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation, which comprises:

[0007] S1: Collect information on aviation electromechanical and hydraulic products and analyze the failure mechanisms of aviation electromechanical and hydraulic products;

[0008] S11: Obtain the material and performance parameters of aviation electromechanical and hydraulic products, the power and control parameters of aviation electromechanical and hydraulic products, as well as the product functional principles and the one-dimensional performance control model of electromechanical and hydraulic products in the aviation electromechanical and hydraulic product database;

[0009] S12: Input component of the failure mechanism analysis process of aviation electromechanical and hydraulic products. It performs structural decomposition, load analysis, mechanism determination and mechanism merging on aviation electromechanical and hydraulic products, completes the failure mechanism analysis, and obtains the sensitive load types and failure mechanisms of each lowest agreed level of aviation electromechanical and hydraulic products;

[0010] S2: Determine the load profiles of each lowest agreed level based on the one-dimensional performance control model of aviation electromechanical and hydraulic products, and conduct stress analysis of aviation electromechanical and hydraulic products;

[0011] S21: Perform load simulation according to the one-dimensional performance control model of the electromechanical and hydraulic product in step S11 to obtain the load profiles of the lowest agreed levels under the product working profile;

[0012] S22: Obtain the load type and failure mechanism of each lowest agreed level of the aviation electromechanical and hydraulic products through the failure mechanism analysis in step S12, determine the type of digital prototype and perform stress simulation analysis to obtain the stress spectrum of each lowest agreed level of the aviation electromechanical and hydraulic products;

[0013] S3: The linear cumulative damage method is used to analyze the durability index of aviation electromechanical and hydraulic products and obtain the wear-out failure time;

[0014] S31: The damage calculation method for aviation electromechanical fluid products belongs to linear cumulative damage. The aviation electromechanical fluid product tree is constructed according to the mechanism analysis results in step S12. The structure of the product tree should be consistent with the mechanism analysis results. The lowest agreed level of aviation electromechanical fluid products is under the set stress level. The damage of the lowest agreed level of aviation electromechanical fluid products in one cycle is:

[0015]

[0016] Where D1 is the damage of the lowest agreed level of the aviation electromechanical fluid product in one cycle; N is the number of cycles when the lowest agreed level of the aviation electromechanical fluid product fails;

[0017] The damage of the lowest agreed level of aviation electromechanical and hydraulic products in n cycles under load level S is:

[0018]

[0019] Among them, D n The damage of the lowest agreed level of aviation electromechanical fluid products in n cycles; n is the number of cycles when failure occurs;

[0020] For any load level S i (i=1,2,…,k), the number of cycles is n i (i=1,2,…,k), when the critical damage of the lowest agreed level of aviation electromechanical and hydraulic products is D CR =1, the linear cumulative damage equation is:

[0021]

[0022] Among them, D CR The lowest agreed level of critical damage for aviation electromechanical and hydraulic products; n i N is the number of cycles of the i-th level load; i is the number of cycles when the i-th level load of the aviation electromechanical and hydraulic product fails; i is the load number; k is the Boltzmann parameter;

[0023] S32: for the aviation electromechanical fluid product tree constructed in step S31, determine the corresponding wear-out failure mechanism model for each node unit of the aviation electromechanical fluid product tree, including: fatigue failure model S, wear failure model V and aging failure model lnL;

[0024] S33: Based on the wear-out failure mechanism model selected in step S32, combined with the material and performance parameters, power and control parameters of the aviation electromechanical and hydraulic products in step S11 and the stress spectrum of the aviation electromechanical and hydraulic products obtained in step S22, at a load level of S i When (i=1,2,…,k), the minimum agreed hierarchical unit failure time T of aviation electromechanical and hydraulic products is calculated as:

[0025]

[0026] Among them, T is the minimum agreed level unit failure time of aviation electromechanical and hydraulic products; t is the single load history time; D is the damage of the unit after a single load history;

[0027] S4: Compare the minimum agreed hierarchical unit failure times of the aviation electromechanical fluid products corresponding to the different wear-out failure mechanism models in step S33, determine the weak links of the aviation electromechanical fluid products, and select the shortest unit failure time as the life of the aviation electromechanical fluid products;

[0028] Preferably, the material and performance parameters of the aviation electromechanical and hydraulic products and the power and control parameters of the aviation electromechanical and hydraulic products in step S11 are specifically:

[0029] The materials and performance parameters of the aviation electromechanical and hydraulic products, including the density, Young's modulus, strength and thermodynamic properties of the materials;

[0030] The power and control parameters of the aviation electromechanical and hydraulic products include overshoot, response time, output torque and position accuracy.

[0031] Preferably, the one-dimensional performance control model of the electromechanical and hydraulic product in step S11 is obtained during the product design stage based on power bond graph theory, Modelica language and VHDL language modeling, which can describe the product functional performance and control principles, and determine the loads on each lowest agreed level of aviation electromechanical and hydraulic products through performance simulation.

[0032] Preferably, the input components of the failure mechanism analysis process of the aviation electromechanical and hydraulic products in step S12 include: product structure information, product working principle and full life cycle mission profile and load spectrum;

[0033] The product structure information includes all the lowest agreed hierarchical units and structural hierarchical relationships of the product, and is provided in the form of a structure decomposition table and a structure decomposition diagram;

[0034] The product working principle reflects the functional logic relationship of the product, including: relative motion relationship, power transfer relationship and constraint relationship, providing a basis for determining the load type of the lowest agreed level unit, and is provided in the form of a schematic diagram or text description;

[0035] The full life cycle mission profile and load spectrum include the working loads and environmental loads experienced by the product during its full life cycle, which need to be distributed by the host from the upper system or determined by the research and development unit based on the functional performance requirements given by the host.

[0036] Preferably, in step S12, the aviation electromechanical and hydraulic products are subjected to structural decomposition, load analysis, mechanism determination and mechanism merging, specifically:

[0037] S121: Structural decomposition requires that the structural decomposition of the product be carried out on the basis of clarifying the product composition, working principle and characteristics, and divided into the initial agreed level, agreed level and minimum agreed level, and a product agreed level diagram or table be drawn to determine the minimum agreed level unit for mechanism analysis;

[0038] S122: Load analysis is to analyze and determine all load types and modes of action of each lowest agreed level in the whole life cycle according to the mission profile and life cycle load spectrum of the product, combined with the motion relationship and constraint relationship between the lowest agreed levels and components of the product, including: working load and environmental load; the working load includes load force, speed, stroke, medium pressure and medium temperature; the environmental load includes vibration and ambient temperature;

[0039] S123: Determination of failure mechanism Based on the structural decomposition and load analysis, for each lowest agreed level unit, analyze and determine all the wear-type failure mechanisms of each lowest agreed level unit; the wear-type failure mechanisms include: fatigue mechanism, aging mechanism, wear mechanism and demagnetization mechanism; the fatigue mechanism is determined based on the principle that when the lowest agreed level unit is subjected to alternating load; the aging mechanism is determined based on the principle that when the material is subjected to temperature load, there will be aging mechanism and performance degradation; the wear mechanism is determined based on the principle that two lowest agreed level units in contact with each other have normal load and relative motion; the demagnetization mechanism is determined based on the principle that the magnetic steel element in the electric drive assembly is subjected to medium or ambient temperature load;

[0040] S124: Mechanism merging: When the load causes the same mechanism and the unit interaction causes the same mechanism, the mechanism is merged. The specific merging principles are:

[0041] The first merging principle is to merge different load types that cause the same mechanism; for the same lowest agreed level unit, the corresponding different load types will produce the same loss mechanism;

[0042] The second merging principle is to merge the mechanisms of different units at the lowest agreed level units that constitute the kinematic pair and unify them into the same mechanism type.

[0043] Preferably, in step S21, load simulation is performed according to the one-dimensional performance control model of the electromechanical and hydraulic product in step S11, specifically:

[0044] Based on the one-dimensional performance control model of electromechanical fluid of aviation electromechanical fluid products, the mission profile and working load spectrum of the product are used as input, and the working load and environmental load spectrum of each lowest agreed level that needs to be simulated in the whole life cycle is obtained through performance simulation in the electromechanical fluid field;

[0045] The input load of electromechanical hydraulic products is the current control signal from the control system, the hydraulic pressure of the upper system, and the load. These are used as initial conditions to input the one-dimensional control performance model to carry out load simulation analysis, obtain the load profile of each lowest agreed level under the product working profile, and provide accurate boundary condition input for subsequent stress analysis;

[0046] For the lowest agreed level with complex loading conditions, a joint simulation is carried out by developing an interface between the one-dimensional performance control model and the stress analysis model to obtain the structural stress or thermal stress at the lowest agreed level.

[0047] Preferably, in step S22, the load type and failure mechanism of each lowest agreed level of aviation electromechanical and hydraulic products are obtained through the failure mechanism analysis in step S12, the digital prototype type is determined and the stress simulation analysis is performed, specifically:

[0048] S221: Build digital prototypes and conduct stress analysis on fatigue mechanisms of aviation electromechanical and hydraulic products, specifically:

[0049] The first type of stress analysis: For aviation electromechanical and hydraulic product parts that only have mechanical stress but are not affected by the vibration environment, a finite element analysis model needs to be established for static analysis;

[0050] The second type of stress analysis: For aviation electromechanical and hydraulic product parts related to the impact of vibration environment, a finite element analysis model needs to be established for vibration stress analysis;

[0051] The third type of stress analysis: For aviation electromechanical and hydraulic product parts that need to consider fluid loads or temperature loads, it is necessary to establish a simulation model for computational fluid dynamics analysis and a finite element analysis model for aviation electromechanical and hydraulic product parts. The pressure field and temperature field results obtained from the simulation analysis are imported into the finite element analysis model through the fluid-solid coupling method for stress analysis.

[0052] S222: For aging mechanisms, establish simulation digital prototypes for sealing components and motor coils in electromechanical fluid products, perform corresponding fluid thermal analysis, obtain temperature fields, and then calculate aging life;

[0053] S223: For wear mechanisms, it is necessary to establish a dynamic model of aviation electromechanical and hydraulic products for simulation analysis, obtain the tangential and normal force loads on the surface of the parts of aviation electromechanical and hydraulic products, and then calculate the wear life;

[0054] S224: For the above-mentioned aviation electromechanical and hydraulic product parts related to load influence, the lowest agreed level load spectrum obtained by the product lowest agreed level load simulation is used as input to establish a lowest agreed level stress simulation digital prototype, and carry out corresponding stress simulation, including structural stress simulation, thermal stress simulation and fluid simulation, to obtain the stress spectrum of each lowest agreed level of aviation electromechanical and hydraulic products.

[0055] Preferably, the fatigue failure model S, the wear failure model V and the aging failure model lnL in step S32 are specifically:

[0056] The fatigue failure model S is obtained based on the stress method of the material SN curve according to the characteristics of electromechanical fluid products and engineering applications:

[0057] S=A(N f ) b

[0058] Where S is the output result of fatigue failure model; N f is the number of cycles; b is the first parameter of the material; A is the second parameter of the material;

[0059] The wear failure model V is specifically an adhesive wear model:

[0060]

[0061] Where V is the output of the wear failure model; K is the wear coefficient; L m is the wear stroke; H is the surface hardness of the material;

[0062] The insulation aging model in the aging failure model is:

[0063]

[0064] Among them, L is the average insulation aging life; G is the material parameter related to insulation; E is the insulation aging model parameter;

[0065] The sealing aging model in the aging failure model is:

[0066]

[0067] Among them, F is the aging reaction rate, and its reciprocal is the aging life; B is the sealing parameter; Ea is the material activation energy parameter; k is the Boltzmann parameter; T1 is the sealing temperature parameter.

[0068] Compared with the prior art, the present invention has the following beneficial effects:

[0069] (1) The present invention establishes a technical process for durability simulation and analysis, provides implementation methods for key technologies such as performance modeling, component load simulation, and stress analysis, and demonstrates the specific implementation process of durability simulation and life prediction of complex electromechanical and hydraulic products based on performance models, proving the feasibility and effectiveness of this method.

[0070] (2) The application of the present invention in durability simulation and life prediction of complex electromechanical fluid products mainly solves the problem of complex loads involved in electromechanical fluid products. By establishing a multi-domain performance model of electromechanical fluids and carrying out performance simulation, the environment and working loads to which each key component is subjected during its entire life cycle are determined;

[0071] (3) The present invention conducts stress simulation analysis under precise loads by directly applying loads or by means of joint simulation, which strongly supports the failure time calculation and life prediction of electromechanical and hydraulic products and improves the accuracy of life calculation results. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 A flow chart of a method for determining the service life of an aviation electromechanical and hydraulic product based on performance model simulation according to the present invention;

[0073] Figure 2 It is a flow chart of the durability simulation analysis method of the electromechanical fluid product of the present invention;

[0074] Figure 3 The flowchart of the performance and reliability integrated modeling technology of the present invention. DETAILED DESCRIPTION

[0075] The exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0076] The embodiment of the present invention uses a certain type of servo valve as the object to carry out durability simulation analysis, establishes a multi-domain performance model and stress simulation model of the product's electromechanical and hydraulic functions, analyzes the wear-out failure time and service life of the product during its service life, evaluates the durability level of the product, and finds durability weaknesses. The present invention provides a method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation, such as Figure 1As shown, collect information on aviation electromechanical fluid products, complete the failure mechanism analysis of aviation electromechanical fluid products based on product failure mode, impact and hazard analysis; determine the load profile of each lowest agreed level based on the one-dimensional performance control model of aviation electromechanical fluid products, and conduct stress analysis of aviation electromechanical fluid products; analyze the durability index of aviation electromechanical fluid products using the linear cumulative damage method to obtain the wear-out failure time; determine the weak links of aviation electromechanical fluid products based on the lowest agreed level with the shortest life in aviation electromechanical fluid products, and obtain the life of aviation electromechanical fluid products; it includes:

[0077] Step S1: Collect information on aviation electromechanical and hydraulic products, and complete failure mechanism analysis of aviation electromechanical and hydraulic products based on product failure modes, impacts, and criticality analysis.

[0078] Step S11: Obtaining the material and performance parameters of the aviation electromechanical and hydraulic products and the power and control parameters of the aviation electromechanical and hydraulic products, as well as the product functional principle and the one-dimensional performance control model of the electromechanical and hydraulic products in the aviation electromechanical and hydraulic product database, specifically:

[0079] The materials and performance parameters of aviation electromechanical and hydraulic products, including density, Young's modulus, strength and thermodynamic properties of the materials; the power and control parameters of aviation electromechanical and hydraulic products, including overshoot, response time, output torque and position accuracy.

[0080] The servo valve of the embodiment of the present invention is mainly composed of a torque motor, a double nozzle baffle and a slide valve. The valve is used to output a brake pressure proportional to the control current for the aircraft, and is a typical electromechanical hydraulic product. Through information collection, the overall structure, working principle, detailed parameters of each component and CAD model are obtained, which is ready for performance model construction, stress analysis and life calculation.

[0081] The one-dimensional performance control model of electromechanical and hydraulic products is obtained during the product design stage based on power bond graph theory, Modelica language and VHDL language modeling. It can describe the product functional performance and control principles, and determine the loads on each lowest agreed level of aviation electromechanical and hydraulic products through performance simulation.

[0082] Step S12: Input components of the failure mechanism analysis process of aviation electromechanical and hydraulic products, structural decomposition, load analysis, mechanism determination and mechanism merging of aviation electromechanical and hydraulic products, complete failure mechanism analysis, and obtain sensitive load types and failure mechanisms of each lowest agreed level of aviation electromechanical and hydraulic products.

[0083] The input components of the failure mechanism analysis process of aviation electromechanical and hydraulic products include: product structure information, product working principle, full life cycle mission profile and load spectrum; product structure information includes all the lowest agreed level units and structure level relationships of the product, and is provided in the form of structure decomposition table and structure decomposition diagram; the product working principle reflects the functional logical relationship of the product, including: relative motion relationship, power transfer relationship and constraint relationship, which provides a basis for determining the load type of the lowest agreed level unit, and is provided in the form of schematic diagram or text description; the full life cycle mission profile and load spectrum include the working load and environmental load experienced by the product throughout its life cycle, which needs to be distributed by the host from the upper system or determined by the research and development unit according to the functional performance requirements given by the host.

[0084] like Figure 2 The general flow chart of the durability simulation test is shown. The main faults and potential wear-out failure mechanisms of all the lowest agreed level units of the servo valve product of the embodiment of the present invention are analyzed within the whole life cycle, and the durability simulation test analysis objectives and modeling requirements are determined, as shown in Appendix 1.

[0085] Appendix 1 Servo valve durability modeling requirements determination table

[0086]

[0087] The specific steps for structural decomposition, load analysis, mechanism determination and mechanism merging of aviation electromechanical and hydraulic products are as follows:

[0088] Step S121: Structural decomposition requires that the product's structure be decomposed based on the clarification of the product's composition, working principle and characteristics, and divided into the initial agreed level, agreed level and minimum agreed level, and a product agreed level diagram or table be drawn to determine the minimum agreed level unit for mechanism analysis.

[0089] Step S122: Load analysis is based on the mission profile and life cycle load spectrum of the product, combined with the motion relationship and constraint relationship between the lowest agreed levels of the product and the components, to analyze and determine all load types and modes of action to which each lowest agreed level is subjected during the entire life cycle, including: working load and environmental load; working load includes load force, rotation speed, stroke, medium pressure and medium temperature; environmental load includes vibration and ambient temperature.

[0090] Step S123: Failure mechanism determination: Based on the structural decomposition and load analysis, for each lowest agreed level unit, analyze and determine all the wear-type failure mechanisms of each lowest agreed level unit; the wear-type failure mechanisms include: fatigue mechanism, aging mechanism, wear mechanism and demagnetization mechanism; the fatigue mechanism is determined based on the principle that when the lowest agreed level unit is subjected to alternating loads; the aging mechanism is determined based on the principle that when the material is subjected to temperature loads, an aging mechanism will exist and lead to performance degradation; the wear mechanism is determined based on the principle that the two lowest agreed level units in contact with each other have normal loads and relative motion; the demagnetization mechanism is determined based on the principle that the magnetic steel elements in the electric drive assembly are subjected to medium or ambient temperature loads.

[0091] Step S124: Mechanism merging: When multiple loads cause the same mechanism, or multiple units interact to cause the same mechanism, the mechanism is merged. The specific merging principles are:

[0092] The first merging principle is to merge different load types that cause the same mechanism; for the same lowest agreed level unit, the corresponding different load types will produce the same loss mechanism.

[0093] The second merging principle is to merge the mechanisms of different units at the lowest agreed level units that constitute the kinematic pair and unify them into the same mechanism type.

[0094] Step S2: Determine the load profiles of each lowest agreed level according to the one-dimensional performance control model of the aviation electromechanical and hydraulic products, and perform stress analysis on the aviation electromechanical and hydraulic products.

[0095] Step S21: Perform load simulation according to the one-dimensional performance control model of the electromechanical and hydraulic product in step S11 to obtain the load profiles of the lowest agreed levels under the product working profile, specifically:

[0096] Based on the one-dimensional performance control model of electromechanical fluid for aviation electromechanical fluid products, with the mission profile and workload spectrum of the product as input, through multi-domain performance simulation of electromechanical fluid, the workload and environmental load spectrum of each lowest agreed level that needs to be simulated during the whole life cycle are obtained.

[0097] The input load of electromechanical hydraulic products is the current control signal from the control system, the hydraulic pressure of the upper system, and the load. These are used as initial conditions to input the one-dimensional control performance model to carry out load simulation analysis, and obtain the load profile of each lowest agreed level under the product working profile, providing accurate boundary condition input for subsequent stress analysis.

[0098] For the lowest agreed level with more complex loading conditions, a joint simulation is carried out by developing an interface between the one-dimensional performance control model and the stress analysis model to obtain the structural stress or thermal stress of the lowest agreed level.

[0099] The embodiment of the present invention follows the electromechanical and hydraulic multi-domain performance modeling method, and establishes a refined performance model of the servo valve based on AMEsim, covering all key parameters of the motor air gap and the valve core housing gap. The performance model mainly consists of three parts: a torque motor, a nozzle baffle assembly, and a slide valve. After the performance model is established, the three key performance parameters of overshoot, response time, and output pressure are simulated and compared with the measured values ​​to verify the accuracy of the model; the electromagnetic force exerted on the armature assembly during operation is simulated and determined using the performance model, and the current step signal under the working state is input into the performance model respectively, and the electromagnetic force exerted on each part of the armature assembly, the relative stroke of the valve core-floating sleeve-valve housing, etc. are simulated to obtain accurate load input for the next step of stress analysis.

[0100] Step S22: Obtain the load type and failure mechanism of each lowest agreed level of aviation electromechanical and hydraulic products through the failure mechanism analysis in step S12, determine the type of digital prototype and perform stress simulation analysis to obtain the stress spectrum of each lowest agreed level of aviation electromechanical and hydraulic products, specifically:

[0101] Step S221: Build a digital prototype and perform stress analysis on the fatigue mechanism of aviation electromechanical and hydraulic products, specifically:

[0102] The first type of stress analysis: For aviation electromechanical and hydraulic product parts that only have mechanical stress but are not affected by the vibration environment, a finite element analysis model needs to be established for static analysis; the second type of stress analysis: For aviation electromechanical and hydraulic product parts that are related to the vibration environment, a finite element analysis model needs to be established for vibration stress analysis; the third type of stress analysis: For aviation electromechanical and hydraulic product parts that need to consider fluid loads or temperature loads, a simulation model needs to be established for computational fluid dynamics analysis, and a finite element analysis model for aviation electromechanical and hydraulic product parts is established. The pressure field and temperature field results obtained from the simulation analysis are imported into the finite element analysis model through the fluid-solid coupling method for stress analysis.

[0103] like Figure 3 The figure shows the flow chart of the performance and reliability integrated modeling technology of the present invention; the armature-baffle-spring tube assembly FEA model and the valve core-valve housing contact FEA simulation model are established through the stress analysis process, and the load obtained by the performance model simulation is used as input to carry out stress simulation to obtain the structural stress response spectrum of the armature assembly under the working task profile and the contact stress response of the valve core assembly.

[0104] Step S222: For the aging mechanism, a simulation digital prototype is established for the sealing components and motor coils in the electromechanical fluid products, and the corresponding fluid thermal analysis is performed to obtain the temperature field, and then the aging life calculation is performed.

[0105] Step S223: For the wear mechanism, a dynamic model of the aviation electromechanical and hydraulic product needs to be established for simulation analysis to obtain the tangential and normal force loads on the surface of the parts of the aviation electromechanical and hydraulic product, and then the wear life calculation is performed.

[0106] Step S224: For the above-mentioned aviation electromechanical and hydraulic product parts related to load influence, the lowest agreed level load spectrum obtained by the product lowest agreed level load simulation is used as input to establish a lowest agreed level stress simulation digital prototype, and carry out corresponding stress simulation, including structural stress simulation, thermal stress simulation and fluid simulation, to obtain the stress spectrum of each lowest agreed level of aviation electromechanical and hydraulic products.

[0107] Step S3: Analyze the durability index of aviation electromechanical and hydraulic products by linear cumulative damage method to obtain the wear-out failure time.

[0108] Step S31: The damage calculation method of the aviation electromechanical fluid product belongs to linear cumulative damage. The aviation electromechanical fluid product tree is constructed according to the mechanism analysis results in step S12. The structure of the product tree should be consistent with the mechanism analysis results. The lowest agreed level of the aviation electromechanical fluid product is under the set stress level. Then, the damage of the lowest agreed level of the aviation electromechanical fluid product in one cycle is:

[0109]

[0110] Among them, D1 is the damage of the lowest agreed level of aviation electromechanical fluid products in one cycle; N is the number of cycles when the lowest agreed level of aviation electromechanical fluid products fails.

[0111] The damage of the lowest agreed level of aviation electromechanical and hydraulic products in n cycles under load level S is:

[0112]

[0113] Among them, D n It is the damage of the lowest agreed level of aviation electromechanical and hydraulic products in n cycles; n is the number of cycles when failure occurs.

[0114] For any load level S i (i=1,2,…,k), the number of cycles is n i (i=1,2,…,k), when the critical damage of the lowest agreed level of aviation electromechanical and hydraulic products is D CR =1, the linear cumulative damage equation is:

[0115]

[0116] Among them, D CR The lowest agreed level of critical damage for aviation electromechanical and hydraulic products; n i N is the number of cycles of the i-th level load;i is the number of cycles when the i-th level load of the aviation electromechanical and hydraulic product fails; i is the load number; k is the Boltzmann parameter.

[0117] Step S32: for the aviation electromechanical fluid product tree constructed in step S31, the corresponding wear-out failure mechanism model is determined for each node unit of the aviation electromechanical fluid product tree, including: fatigue failure model S, wear failure model V and aging failure model L, specifically:

[0118] The fatigue failure model S is obtained based on the characteristics of electromechanical and hydraulic products and engineering applications. The stress method based on the material SN curve is:

[0119] S=A(N f ) b ;

[0120] Where S is the output result of fatigue failure model; N f is the number of cycles; b is the first parameter of the material; A is the second parameter of the material.

[0121] The wear failure model V is specifically an adhesive wear model:

[0122]

[0123] Where V is the output of the wear failure model; k is the wear coefficient; L m is the wear stroke; H is the surface hardness of the material.

[0124] The insulation aging model in the aging failure model is:

[0125]

[0126] Among them, L is the average insulation aging life; G is the material parameter related to insulation; E is the insulation aging model parameter.

[0127] The seal aging model in the aging failure model is:

[0128]

[0129] Among them, F is the aging reaction rate, and its reciprocal is the aging life; B is the sealing parameter; Ea is the material activation energy parameter; k is the Boltzmann parameter; T1 is the sealing temperature parameter.

[0130] Step S33: Based on the wear-out failure mechanism model selected in step S32, combined with the material and performance parameters, power and control parameters of the aviation electromechanical and hydraulic products in step S11 and the stress spectrum of the aviation electromechanical and hydraulic products obtained in step S22, at a load level of S i When (i=1,2,…,k), the minimum agreed hierarchical unit failure time T of aviation electromechanical and hydraulic products is calculated as:

[0131]

[0132] Among them, T is the minimum agreed level unit failure time of aviation electromechanical and hydraulic products; t is the single load history time; D is the damage of the unit after a single load history.

[0133] The embodiment of the present invention takes the structural stress response spectrum of the armature assembly under the working task profile and the contact stress response of the valve core assembly as input, and respectively uses the nominal stress method fatigue life calculation model and the Archard wear life calculation model to analyze and obtain the fatigue life of the armature, baffle, and spring tube and the wear life of the valve core and housing.

[0134] Step S4: Compare the minimum agreed hierarchical unit failure times of the aviation electromechanical and hydraulic products corresponding to the different wear-out failure mechanism models in step S33, determine the weak links of the aviation electromechanical and hydraulic products, and select the shortest unit failure time as the life of the aviation electromechanical and hydraulic products.

[0135] The life assessment and weak link determination of the present invention, based on the simulation calculation results and comparing the durability index requirements, determine that among the five key minimum agreed levels of the servo valve product, the wear-type failure time of the spring tube is 3568 times, which does not meet the total life requirements and is a weak link of the product. Therefore, the first occurrence time of the wear-type failure of the servo valve product is 3568 times. For specific results, see Appendix 2. The reason for the analysis is that the spring tube, as a key component, has a large deformation amount, large structural stress, and is frequently used under actual use conditions. In view of the relatively low service life of the spring tube as a weak link, it is recommended to optimize the structural size and stiffness design of the spring tube in combination with the product functional performance requirements.

[0136] Table 2 Servo valve service life calculation example

[0137]

[0138]

[0139] The beneficial effects of the present invention are as follows: the present invention provides a method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation. The embodiment of the present invention establishes a technical process for durability simulation analysis, studies and provides implementation methods for key technologies such as failure mechanism analysis, component load simulation, and stress analysis. Taking a certain type of servo valve as an example, the specific implementation process of durability simulation and life prediction of complex electromechanical and hydraulic products based on performance models is demonstrated, and the feasibility and effectiveness of the technical method are preliminarily proved; the application in durability simulation and life prediction of complex electromechanical and hydraulic products mainly solves the problem that electromechanical and hydraulic products involve complex loads and the loads on components are difficult to obtain accurately. The embodiment of the present invention uses a multi-domain performance model of electromechanical and hydraulic to carry out performance simulation and determine the environment and working loads to which each key component is subjected during the entire life cycle; by directly applying loads or joint simulation, stress simulation analysis under precise loads is carried out, which strongly supports the calculation of product failure time and life prediction, and improves the accuracy of life calculation results.

[0140] The embodiments described above are only descriptions of the preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation, characterized in that: It includes: S1: Collect information on aviation electromechanical and hydraulic products and analyze the failure mechanisms of aviation electromechanical and hydraulic products; S11: Obtain the material and performance parameters of aviation electromechanical and hydraulic products, the power and control parameters of aviation electromechanical and hydraulic products, as well as the product functional principles and the one-dimensional performance control model of electromechanical and hydraulic products in the aviation electromechanical and hydraulic product database; S12: Input component of the failure mechanism analysis process of aviation electromechanical and hydraulic products. It performs structural decomposition, load analysis, mechanism determination and mechanism merging on aviation electromechanical and hydraulic products, completes the failure mechanism analysis, and obtains the sensitive load types and failure mechanisms of each lowest agreed level of aviation electromechanical and hydraulic products; S2: Determine the load profiles of each lowest agreed level based on the one-dimensional performance control model of aviation electromechanical and hydraulic products, and conduct stress analysis of aviation electromechanical and hydraulic products; S21: Perform load simulation according to the one-dimensional performance control model of the electromechanical and hydraulic product in step S11 to obtain the load profiles of the lowest agreed levels under the product working profile; S22: Obtain the load type and failure mechanism of each lowest agreed level of the aviation electromechanical and hydraulic products through the failure mechanism analysis in step S12, determine the type of digital prototype and perform stress simulation analysis to obtain the stress spectrum of each lowest agreed level of the aviation electromechanical and hydraulic products; S3: The linear cumulative damage method is used to analyze the durability index of aviation electromechanical and hydraulic products and obtain the wear-out failure time; S31: The damage calculation method for aviation electromechanical fluid products belongs to linear cumulative damage. The aviation electromechanical fluid product tree is constructed according to the mechanism analysis results in step S12. The structure of the product tree should be consistent with the mechanism analysis results. The lowest agreed level of aviation electromechanical fluid products is under the set stress level. The damage of the lowest agreed level of aviation electromechanical fluid products in one cycle is: Where D1 is the damage of the lowest agreed level of the aviation electromechanical fluid product in one cycle; N is the number of cycles when the lowest agreed level of the aviation electromechanical fluid product fails; The damage of the lowest agreed level of aviation electromechanical and hydraulic products in n cycles under load level S is: Among them, D n The damage of the lowest agreed level of aviation electromechanical fluid products in n cycles; n is the number of cycles when failure occurs; For any load level S i (i=1,2,…,k), the number of cycles is n i (i=1,2,…,k), when the critical damage of the lowest agreed level of aviation electromechanical and hydraulic products is D CR =1, the linear cumulative damage equation is: Among them, D CR The lowest agreed level of critical damage for aviation electromechanical and hydraulic products; n i N is the number of cycles of the i-th level load; i is the number of cycles when the i-th level load of the aviation electromechanical and hydraulic product fails; i is the load number; k is the Boltzmann parameter; S32: for the aviation electromechanical fluid product tree constructed in step S31, determine the corresponding wear-out failure mechanism model for each node unit of the aviation electromechanical fluid product tree, including: fatigue failure model S, wear failure model V and aging failure model lnL; S33: Based on the wear-out failure mechanism model selected in step S32, combined with the material and performance parameters, power and control parameters of the aviation electromechanical and hydraulic products in step S11 and the stress spectrum of the aviation electromechanical and hydraulic products obtained in step S22, at a load level of S i When (i=1,2,…,k), the minimum agreed hierarchical unit failure time T of aviation electromechanical and hydraulic products is calculated as: Among them, T is the minimum agreed level unit failure time of aviation electromechanical and hydraulic products; t is the single load history time; D is the damage of the unit after a single load history; S4: Compare the minimum agreed hierarchical unit failure times of the aviation electromechanical and hydraulic products corresponding to the different wear-out failure mechanism models in step S33, determine the weak links of the aviation electromechanical and hydraulic products, and select the shortest unit failure time as the service life of the aviation electromechanical and hydraulic products.

2. The method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation according to claim 1, characterized in that: The material and performance parameters of the aviation electromechanical and hydraulic products and the power and control parameters of the aviation electromechanical and hydraulic products in step S11 are specifically: The materials and performance parameters of the aviation electromechanical and hydraulic products, including the density, Young's modulus, strength and thermodynamic properties of the materials; The power and control parameters of the aviation electromechanical and hydraulic products include overshoot, response time, output torque and position accuracy.

3. The method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation according to claim 1 is characterized in that: The one-dimensional performance control model of the electromechanical and hydraulic products in step S11 is obtained during the product design phase based on power bond graph theory, Modelica language and VHDL language modeling, and the loads on each lowest agreed level of the aviation electromechanical and hydraulic products are determined through performance simulation.

4. The method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation according to claim 1, characterized in that: The input components of the failure mechanism analysis process of the aviation electromechanical and hydraulic products in step S12 include: product structure information, product working principle and full life cycle mission profile and load spectrum; The product structure information includes all the lowest agreed hierarchical units and structural hierarchical relationships of the product, and is provided in the form of a structure decomposition table and a structure decomposition diagram; The product working principle reflects the functional logic relationship of the product, including: relative motion relationship, power transfer relationship and constraint relationship, providing a basis for determining the load type of the lowest agreed level unit, and is provided in the form of a schematic diagram or text description; The full life cycle mission profile and load spectrum include the working loads and environmental loads experienced by the product during its full life cycle, which need to be distributed by the host from the upper system or determined by the research and development unit based on the functional performance requirements given by the host.

5. The method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation according to claim 1 is characterized by: In step S12, the aviation electromechanical and hydraulic products are subjected to structural decomposition, load analysis, mechanism determination and mechanism merging, specifically: S121: Structural decomposition requires that the structural decomposition of the product be carried out on the basis of clarifying the product composition, working principle and characteristics, and divided into the initial agreed level, agreed level and minimum agreed level, and a product agreed level diagram or table be drawn to determine the minimum agreed level unit for mechanism analysis; S122: Load analysis is to analyze and determine all load types and modes of action of each lowest agreed level in the whole life cycle according to the mission profile and life cycle load spectrum of the product, combined with the motion relationship and constraint relationship between the lowest agreed levels and components of the product, including: working load and environmental load; the working load includes load force, speed, stroke, medium pressure and medium temperature; the environmental load includes vibration and ambient temperature; S123: Determination of failure mechanism Based on the structural decomposition and load analysis, for each lowest agreed level unit, analyze and determine all the wear-type failure mechanisms of each lowest agreed level unit; the wear-type failure mechanisms include: fatigue mechanism, aging mechanism, wear mechanism and demagnetization mechanism; the fatigue mechanism is determined based on the principle that when the lowest agreed level unit is subjected to alternating load; the aging mechanism is determined based on the principle that when the material is subjected to temperature load, there will be aging mechanism and performance degradation; the wear mechanism is determined based on the principle that two lowest agreed level units in contact with each other have normal load and relative motion; the demagnetization mechanism is determined based on the principle that the magnetic steel element in the electric drive assembly is subjected to medium or ambient temperature load; S124: Mechanism merging: When the load causes the same mechanism and the unit interaction causes the same mechanism, the mechanism is merged. The specific merging principles are: The first merging principle is to merge different load types that cause the same mechanism; for the same lowest agreed level unit, the corresponding different load types will produce the same loss mechanism; The second merging principle is to merge the mechanisms of different units at the lowest agreed level units that constitute the kinematic pair and unify them into the same mechanism type.

6. The method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation according to claim 1, characterized in that: In step S21, load simulation is performed according to the one-dimensional performance control model of the electromechanical and hydraulic product in step S11, specifically: Based on the one-dimensional performance control model of electromechanical fluid of aviation electromechanical fluid products, the mission profile and working load spectrum of the product are used as input, and the working load and environmental load spectrum of each lowest agreed level that needs to be simulated in the whole life cycle is obtained through performance simulation in the electromechanical fluid field; The input load of electromechanical hydraulic products is the current control signal from the control system, the hydraulic pressure of the upper system, and the load. These are used as initial conditions to input the one-dimensional control performance model to carry out load simulation analysis, obtain the load profile of each lowest agreed level under the product working profile, and provide accurate boundary condition input for subsequent stress analysis; For the lowest agreed level with complex loading conditions, a joint simulation is carried out by developing an interface between the one-dimensional performance control model and the stress analysis model to obtain the structural stress or thermal stress at the lowest agreed level.

7. The method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation according to claim 1, characterized in that: In step S22, the load type and failure mechanism of each lowest agreed level of aviation electromechanical and hydraulic products are obtained through the failure mechanism analysis in step S12, the digital prototype type is determined and stress simulation analysis is performed, specifically: S221: Build digital prototypes and conduct stress analysis on fatigue mechanisms of aviation electromechanical and hydraulic products, specifically: The first type of stress analysis: For aviation electromechanical and hydraulic product parts that only have mechanical stress but are not affected by the vibration environment, a finite element analysis model needs to be established for static analysis; The second type of stress analysis: For aviation electromechanical and hydraulic product parts related to the impact of vibration environment, a finite element analysis model needs to be established for vibration stress analysis; The third type of stress analysis: For aviation electromechanical and hydraulic product parts that need to consider fluid loads or temperature loads, it is necessary to establish a simulation model for computational fluid dynamics analysis and a finite element analysis model for aviation electromechanical and hydraulic product parts. The pressure field and temperature field results obtained from the simulation analysis are imported into the finite element analysis model through the fluid-solid coupling method for stress analysis. S222: For aging mechanisms, establish simulation digital prototypes for sealing components and motor coils in electromechanical fluid products, perform corresponding fluid thermal analysis, obtain temperature fields, and then calculate aging life; S223: For wear mechanisms, it is necessary to establish a dynamic model of aviation electromechanical and hydraulic products for simulation analysis, obtain the tangential and normal force loads on the surface of the parts of aviation electromechanical and hydraulic products, and then calculate the wear life; S224: For the above-mentioned aviation electromechanical and hydraulic product parts related to load influence, the lowest agreed level load spectrum obtained by the product lowest agreed level load simulation is used as input to establish a lowest agreed level stress simulation digital prototype, and carry out corresponding stress simulation, including structural stress simulation, thermal stress simulation and fluid simulation, to obtain the stress spectrum of each lowest agreed level of aviation electromechanical and hydraulic products.

8. The method for determining the service life of aviation electromechanical and hydraulic products based on performance model simulation according to claim 1, characterized in that: The fatigue failure model S, the wear failure model V and the aging failure model lnL in step S32 are specifically: The fatigue failure model S is obtained based on the stress method of the material SN curve according to the characteristics of electromechanical fluid products and engineering applications: S=A(N f ) b Where S is the output result of fatigue failure model; N f is the number of cycles; b is the first parameter of the material; A is the second parameter of the material; The wear failure model V is specifically an adhesive wear model: Where V is the output of the wear failure model; K is the wear coefficient; L m is the wear stroke; H is the surface hardness of the material; The insulation aging model in the aging failure model is: Among them, L is the average insulation aging life; G is the material parameter related to insulation; E is the insulation aging model parameter; The sealing aging model in the aging failure model is: Among them, F is the aging reaction rate, and its reciprocal is the aging life; B is the sealing parameter; Ea is the material activation energy parameter; k is the Boltzmann parameter; T1 is the sealing temperature parameter.

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