Method for determining service life of aviation electro-hydraulic product based on performance model simulation

Abstract

The application 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 electro-hydraulic product based on performance model simulation, which comprises the following steps: S1, collecting information of the aviation electro-hydraulic product, and completing failure mechanism analysis of the aviation electro-hydraulic product according to product failure mode, influence and hazard degree analysis; S2, determining the load profile of each minimum agreed level according to a one-dimensional performance control model of the aviation electro-hydraulic product, and performing stress analysis of the aviation electro-hydraulic product; S3, analyzing the durability index of the aviation electro-hydraulic product by using a linear cumulative damage method, and obtaining a wear-out failure time; and S4, determining the weak link of the aviation electro-hydraulic product according to the minimum agreed level with the shortest service life in the aviation electro-hydraulic product, and obtaining the service life of the aviation electro-hydraulic product. Through full-life-cycle performance simulation, the load information and boundary conditions of the minimum agreed level of the electro-hydraulic product are obtained, and stress analysis and wear-out failure time calculation are realized.

Description

TECHNICAL FIELD

[0001] The application 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 electro-hydraulic product based on performance model simulation. BACKGROUND

[0002] Aviation airborne mechanical products mainly include hydraulic and pneumatic devices such as actuators, valves, pumps, valves, locks, etc., electromechanical devices such as electromechanical actuators, generators, electric seats, etc., and motion mechanisms such as locking mechanisms, control mechanisms, and retracting mechanisms, which are widely used in flight control, fuel, hydraulic, environmental control, landing devices and other key airborne systems that directly affect the safety and mission of the aircraft. Among them, complex products such as electromagnetic valves and servo actuators involving multiple fields of electro-hydraulic are the key to affecting the function and reliability of each system.

[0003] At present, during the development of aviation products, durability simulation tests are usually carried out based on the generalized stress-strength and cumulative damage principles and computer technology. By simulating the load history experienced by the product, including working load and environmental load, on the digital prototype of the product, the load is decomposed to the lowest agreed level unit, stress analysis is carried out, and the failure model is used to calculate the wear-type failure time of each component. According to the principle of the shortest time, the service life of the product, i.e. the wear-type failure first occurrence time, is determined, so as to find out the weak link of the product's durability and evaluate the durability level of the product.

[0004] Due to the diversity of the load and the complexity of the working principle of the aviation electro-hydraulic product, the current durability simulation has the following problems, mainly in the following aspects: the electro-hydraulic product involves complex load, and the load on the components is difficult to accurately obtain. In the durability simulation test of general aviation products, the lowest agreed level load needs to be obtained by product load decomposition, among which the load of some components can be directly determined by product design information, and the load involving mechanism dynamics, such as connecting rod speed and cam torque, can be obtained by multi-body dynamics and rotor dynamics simulation analysis. However, the load of complex products in multiple fields of electro-hydraulic, such as the electromagnetic force on the armature of the jet valve, the medium pressure load spectrum in the spool cavity, and the motor coil current, is difficult to obtain, and depends on the experience of product designers for value selection, which leads to a decrease in the accuracy of stress analysis results and inaccuracy of wear-type failure time. SUMMARY

[0005] In response to the shortcomings of the existing technology, 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 the electromechanical and hydraulic products of the products is established. Through performance simulation throughout the entire 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 through an interface to carry out joint simulation, so as to realize stress analysis and wear-type failure time calculation under accurate load conditions, thereby ultimately improving the analysis accuracy of the service life and the confidence level of the durability simulation results.

[0006] To achieve the above objectives, 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, comprising:

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

[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 from the aviation electromechanical and hydraulic product database;

[0009] S12: The input component of the failure mechanism analysis process of aviation electro-hydraulic products. It performs structural decomposition, load analysis, mechanism determination and mechanism merging on aviation electro-hydraulic products to complete the failure mechanism analysis and obtain the sensitive load types and failure mechanisms of each lowest agreed level of aviation electro-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 based on the one-dimensional performance control model of the electromechanical and hydraulic product in step S11 to obtain the load profiles of each lowest agreed level 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 product 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 product;

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

[0014] S31: The damage calculation method for aviation electromechanical fluid products is linear cumulative damage. Based on the mechanism analysis results in step S12, an aviation electromechanical fluid product tree is constructed. The structure of the product tree should be consistent with the mechanism analysis results. 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 aviation electromechanical fluid products in one cycle; N is the number of cycles when the lowest agreed level of aviation electromechanical fluid products 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 to the lowest agreed level of aviation electromechanical and hydraulic products after 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 is the number of cycles of the i-th level load; N i is the number of cycles when the aircraft electromechanical and hydraulic product fails under the i-th load; i is the load number; k is the Boltzmann parameter;

[0023] S32: for the aviation electromechanical and hydraulic product tree constructed in step S31, determine the corresponding wear-out failure mechanism model for each node unit of the aviation electromechanical and hydraulic 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 product in step S11 and the stress spectrum of the aviation electromechanical and hydraulic product obtained in step S22, the load level is 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] Wherein, 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 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;

[0028] Preferably, the material and performance parameters of the aviation electromechanical and hydraulic product and the power and control parameters of the aviation electromechanical and hydraulic product 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 electro-hydraulic product 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 product 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 of the product, including relative motion relationship, power transfer relationship and constraint relationship, and provides a basis for determining the load type of the lowest agreed level unit. It 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 aircraft electromechanical and hydraulic products are subjected to structural decomposition, load analysis, mechanism determination, and mechanism merging, specifically:

[0037] S121: Structural decomposition requires clarifying the product's composition, working principle, and characteristics. The product's structural decomposition should be divided into the initial agreed level, agreed level, and lowest agreed level. A product agreed level diagram or table should be drawn to determine the lowest agreed level unit for mechanism analysis.

[0038] S122: Load analysis is based on the product's mission profile and life cycle load spectrum, combined with the product's lowest agreed levels and the motion and constraint relationships between components. It analyzes and determines all load types and modes of action to which each lowest agreed level is subjected throughout its life cycle. Specifically, it includes: operational loads and environmental loads. The operational loads include load force, speed, stroke, medium pressure, and medium temperature. The environmental loads include vibration and ambient temperature.

[0039] S123: Failure mechanism determination: Based on the structural decomposition and load analysis, for each lowest agreed level unit, analyze and determine all 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 occur and lead to performance degradation; the wear mechanism is determined based on the principle that 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;

[0040] S124: Mechanism merging is performed when the load causes the same mechanism or the unit interaction causes the same mechanism. 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 the electromechanical fluid of aviation electromechanical fluid products, the mission profile and workload spectrum of the product are used as input. Through electromechanical fluid field performance simulation, the workload and environmental load spectrum of each lowest agreed level that needs to be simulated throughout the entire life cycle are obtained;

[0045] The input loads of electromechanical and hydraulic products are 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 into a one-dimensional control performance model for load simulation analysis. This obtains the load profiles of each lowest agreed level under the product's operating profile, providing 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 electro-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:

[0048] S221: Build digital prototypes and perform 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 are only subject to mechanical stress but 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 parts that are affected by vibration environments, a finite element analysis model needs to be established for vibration stress analysis.

[0051] The third type of stress analysis: For aircraft electromechanical and hydraulic parts that need to consider fluid loads or temperature loads, simulation models need to be established for computational fluid dynamics analysis. A finite element analysis model is established for the aircraft electromechanical and hydraulic parts. The pressure and temperature field results obtained from the simulation analysis are imported into the finite element analysis model through the fluid-structure coupling method for stress analysis.

[0052] S222: Targeting aging mechanisms, we build simulation digital prototypes for sealing components and motor coils in electromechanical fluid products, conduct corresponding fluid thermal analysis, obtain the temperature field, and then perform aging life calculations.

[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 parts of aviation electromechanical and hydraulic products related to load influence, the lowest agreed level load spectrum obtained by the lowest agreed level load simulation of the product 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] Among them, 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] Wherein, 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 application establishes a durability simulation analysis technical process, gives the implementation method of key technologies such as performance modeling, component load simulation and stress analysis, shows the specific implementation process of the durability simulation and life prediction of the mechatronic and hydrodynamic complex product based on the performance model, and proves the feasibility and effectiveness of the method.

[0070] (2) The application of the durability simulation and life prediction of the mechatronic and hydrodynamic complex product mainly solves the problem of complex load involved in the mechatronic and hydrodynamic product, determines the environmental and working load of each key component in the whole life cycle by establishing the performance model of the mechatronic and hydrodynamic multi-field and carrying out performance simulation.

[0071] (3) The application carries out stress simulation analysis under precise load through direct load application or combined simulation, effectively supports the failure time calculation and life prediction of the mechatronic and hydrodynamic product, and improves the accuracy of the life calculation result. BRIEF DESCRIPTION OF DRAWINGS

[0072] Figure 1 The flow chart of the service life determination method of the aviation mechatronic and hydrodynamic product based on the performance model simulation of the application;

[0073] Figure 2 The flow chart of the durability simulation analysis method of the mechatronic and hydrodynamic product of the application;

[0074] Figure 3 The flow chart of the performance and reliability integrated modeling technology of the application. DETAILED DESCRIPTION

[0075] The exemplary embodiments, features and aspects of the application will be described in detail below with reference to the accompanying drawings. The same reference signs in the drawings represent functionally identical or similar elements. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0076] The embodiment of the application takes a certain type of servo valve as the object to carry out durability simulation analysis, establishes the mechatronic and hydrodynamic multi-field performance model and stress simulation model of the product, analyzes the wear-type failure time and service life of the product in the life cycle, evaluates the durability level of the product, and finds out the weak links of durability. The application provides a service life determination method of an aviation mechatronic and hydrodynamic product based on performance model simulation, as shown in Figure 1As shown, information on aviation electromechanical and hydraulic products is collected, and the failure mechanism analysis of aviation electromechanical and hydraulic products is completed based on the product failure mode, impact and criticality analysis; the load profile of each lowest agreed level is determined based on the one-dimensional performance control model of aviation electromechanical and hydraulic products, and stress analysis of aviation electromechanical and hydraulic products is performed; the durability index of aviation electromechanical and hydraulic products is analyzed using the linear cumulative damage method to obtain the wear-out type failure time; based on the lowest agreed level with the shortest life among aviation electromechanical and hydraulic products, the weak links of aviation electromechanical and hydraulic products are determined to obtain the life of aviation electromechanical and hydraulic 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: Obtain the material and performance parameters of the aircraft electromechanical and hydraulic products, the power and control parameters of the aircraft electromechanical and hydraulic products, as well as the product functional principles and the one-dimensional performance control model of the electromechanical and hydraulic products from the aircraft electromechanical and hydraulic product database, specifically:

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

[0080] The servo valve in this embodiment of the present invention primarily consists of a torque motor, a dual-nozzle baffle, and a slide valve. This valve is used to output aircraft brake pressure proportional to the control current and is a typical electro-hydraulic product. Information collection revealed the overall structure, operating principle, detailed parameters of each component, and a CAD model, paving the way for performance modeling, stress analysis, and lifespan calculations.

[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's functional performance and control principles, and determine the loads at 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 the aircraft electromechanical and hydraulic products, perform structural decomposition, load analysis, mechanism determination and mechanism merging on the aircraft electromechanical and hydraulic products, complete the failure mechanism analysis, and obtain the sensitive load type and failure mechanism of each lowest agreed level of the aircraft electromechanical and hydraulic products.

[0083] The input components of the failure mechanism analysis process of aviation electro-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 structural hierarchy 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, providing 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 following is a general flow chart for the durability simulation test. The main faults and potential wear-out failure mechanisms of all lowest-level units of the servo valve product in the embodiment of the present invention were analyzed throughout their life cycle, and the durability simulation test analysis objectives and modeling requirements were 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. The structure is divided into the initial agreed level, agreed level, and lowest agreed level. A product agreed level diagram or table is drawn to determine the lowest agreed level unit for mechanism analysis.

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

[0090] Step S123: Failure mechanism determination Based on the structure decomposition and load analysis, for each minimum agreed level unit, all the damage type failure mechanisms of each minimum agreed level unit are analyzed and determined. The damage type failure mechanisms include fatigue mechanism, aging mechanism, wear mechanism and demagnetization mechanism. The fatigue mechanism determination principle is that the minimum agreed level unit is subjected to alternating load. The aging mechanism determination principle is that the material is subjected to temperature load, the aging mechanism exists and leads to performance degradation. The wear mechanism determination principle is that the two minimum agreed level units in contact exist normal load and relative motion. The demagnetization mechanism determination principle is that the magnetic steel element in the electric drive assembly is subjected to medium or environmental temperature load.

[0091] Step S124: Mechanism merging When the same mechanism is caused by multiple loads and the same mechanism is caused by the interaction of multiple units, mechanism merging is performed. The specific merging principles are as follows:

[0092] The first merging principle is to merge different load types that cause the same mechanism. For the same minimum agreed level unit, different load types corresponding to the same minimum agreed level unit will produce the same damage mechanism.

[0093] The second merging principle is to merge the mechanisms of different units for the minimum agreed level units constituting the motion pair, and unify them into the same mechanism type.

[0094] Step S2: Determine the load profile of each minimum agreed level according to the one-dimensional performance control model of the aero electromechanical hydraulic product, and perform stress analysis of the aero electromechanical hydraulic product.

[0095] Step S21: Perform load simulation according to the one-dimensional performance control model of the electromechanical hydraulic product in step S11 to obtain the load profile of each minimum agreed level under the product working profile. Specifically:

[0096] Based on the electromechanical hydraulic one-dimensional performance control model of the aero electromechanical hydraulic product, the task profile and working load spectrum of the product are input, and through electromechanical hydraulic multi-field performance simulation, the working load and environmental load spectrum of each minimum agreed level in the whole life cycle are obtained.

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

[0098] For the minimum agreed level with complex load conditions, 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 minimum agreed level.

[0099] This embodiment of the present invention follows a multi-domain electromechanical and hydraulic performance modeling approach and establishes a refined performance model of the servo valve based on AMEsim, covering all key parameters including motor air gap and valve core housing clearance. The performance model primarily consists of three components: the torque motor, the nozzle baffle assembly, and the spool valve. After the performance model is established, three key performance parameters, overshoot, response time, and output pressure, are simulated and compared with measured values ​​to verify the model's accuracy. The performance model is then used to simulate and determine the electromagnetic force acting on the armature assembly during operation. Current step signals under operating conditions are then input into the performance model to simulate the electromagnetic force acting on each component of the armature assembly, as well as the relative travel of the valve core, floating sleeve, and valve housing, providing accurate load input for subsequent stress analysis.

[0100] Step S22: Obtain the load type and failure mechanism of each lowest agreed level of the aviation electromechanical and hydraulic product 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 product, 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 are only subject to 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. A finite element analysis model of the aviation electromechanical and hydraulic product parts is established, and 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 FEA model of the armature-baffle-spring tube assembly and the FEA simulation model of the valve core-valve housing contact 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 aging mechanisms, a simulation digital prototype is established for the sealing components and motor coils in electromechanical fluid products, and corresponding fluid thermal analysis is performed to obtain the temperature field, and then the aging life calculation is performed.

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

[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 corresponding stress simulation is carried out, including structural stress simulation, thermal stress simulation and fluid simulation, to obtain the stress spectrum of each lowest agreed level of the aviation electromechanical and hydraulic product.

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

[0108] Step S31: The damage calculation method for aviation electromechanical fluid products is linear cumulative damage. Based on the mechanism analysis results in step S12, an aviation electromechanical fluid product tree is constructed. The structure of the product tree should be consistent with the mechanism analysis results. Under the set stress level, 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 and hydraulic products in one cycle; N is the number of cycles when the lowest agreed level of aviation electromechanical and hydraulic 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 electro-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 is the number of cycles of the i-th level load; Ni is the cycle number of the i-th load level; k is the Boltzmann parameter.

[0117] Step S32: For the aviation electro-hydraulic product tree constructed in step S31, a corresponding wear-type failure mechanism model is determined for each node unit of the aviation electro-hydraulic product tree, including a fatigue failure model S, a wear failure model V, and an aging failure model L, which are specifically:

[0118] The fatigue failure model S is a stress method based on the S-N curve of the material according to the characteristics and engineering applications of the electro-hydraulic product:

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

[0120] Wherein, S is the output result of the fatigue failure model; N f is the cycle number; 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] Wherein, V is the output of the wear failure model; k is the wear coefficient; L m is the wear travel; H is the surface hardness of the material.

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

[0125]

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

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

[0128]

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

[0130] Step S33: According to the wear-type failure mechanism model selected in step S32, combined with the material and performance parameters of the aviation electro-hydraulic product in step S11, the power and control parameters, and the stress spectrum of the aviation electro-hydraulic product obtained in step S22, the failure time T of the lowest agreed level unit of the aviation electro-hydraulic product is calculated when the load level is S i (i = 1, 2, …, k).

[0131]

[0132] Among them, T is the minimum agreed level unit failure time of aviation electro-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 uses 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 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 present invention's lifespan assessment and weak link identification, based on simulation calculation results and comparison with durability index requirements, determined that, among the five key minimum agreed levels of the servo valve product, the spring tube's wear-out failure time of 3568 times does not meet the total lifespan requirement, making it a weak link in the product. Therefore, the first occurrence of wear-out failures in the servo valve product is 3568 times. Detailed results are shown in Appendix 2. Analysis reveals that the spring tube, as a key component, experiences significant deformation and structural stress under actual operating conditions, resulting in frequent use. Given that the spring tube's relatively low service life represents a weak link, it is recommended to optimize its structural dimensions and stiffness design in accordance with the product's 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 of 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 the electromechanical and hydraulic multi-domain performance model 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 merely descriptions of preferred implementations of the present invention and are not intended to limit the scope of the present invention. Without departing from the 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 fall within the scope of protection 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 their failure mechanisms; 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 from the aviation electromechanical and hydraulic product database; S12: The input component of the failure mechanism analysis process of aviation electro-hydraulic products. It performs structural decomposition, load analysis, mechanism determination and mechanism merging on aviation electro-hydraulic products to complete the failure mechanism analysis and obtain the sensitive load types and failure mechanisms of each lowest agreed level of aviation electro-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 based on the one-dimensional performance control model of the electromechanical and hydraulic product in step S11 to obtain the load profiles of each lowest agreed level under the product working profile; S22: Obtain the load type and failure mechanism of each lowest agreed level of the aviation electromechanical and hydraulic product 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 product; In step S22, the load type and failure mechanism of each lowest agreed level of aviation electro-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 perform 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 are only subject to mechanical stress but 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 parts that are affected by vibration environments, a finite element analysis model needs to be established for vibration stress analysis. The third type of stress analysis: For aircraft electromechanical and hydraulic parts that need to consider fluid loads or temperature loads, simulation models need to be established for computational fluid dynamics analysis. A finite element analysis model is established for the aircraft electromechanical and hydraulic parts. The pressure and temperature field results obtained from the simulation analysis are imported into the finite element analysis model through the fluid-structure coupling method for stress analysis. S222: Targeting aging mechanisms, we build simulation digital prototypes for sealing components and motor coils in electromechanical fluid products, conduct corresponding fluid thermal analysis, obtain the temperature field, and then perform aging life calculations. 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: Using the lowest agreed level load spectrum obtained from the lowest agreed level load simulation of the aircraft electromechanical and hydraulic product parts related to load influence as input, a lowest agreed level stress simulation digital prototype is established, and corresponding stress simulations are performed, including structural stress simulation, thermal stress simulation, and fluid simulation, to obtain stress spectra of each lowest agreed level of the aircraft electromechanical and hydraulic product. S3: The linear cumulative damage method is used to analyze the durability indicators of aviation electromechanical and hydraulic products and obtain the wear-out failure time; S31: The damage calculation method for aviation electromechanical fluid products is linear cumulative damage. Based on the mechanism analysis results in step S12, an aviation electromechanical fluid product tree is constructed. The structure of the product tree should be consistent with the mechanism analysis results. Under the set stress level, the damage of the lowest agreed level of aviation electromechanical fluid products in one cycle is: ； in, The minimum agreed level of damage to aviation electromechanical fluid products in one cycle; The number of cycles required for failure of the lowest agreed level of aviation electromechanical and hydraulic products; At load level The lowest agreed level for aviation electromechanical and hydraulic products is The damage of the sub-cycle is: ； in, The minimum agreed level for aviation electromechanical and hydraulic products is Subcirculatory damage; is the number of cycles when failure occurs; For any load level , the number of cycles is , when the critical damage of the lowest agreed level of aviation electromechanical fluid products is =1, the linear cumulative damage equation is obtained as: ； in, This is the lowest agreed level of critical damage for aviation electro-hydraulic products; For the Number of cycles of level load; For aviation electromechanical fluid products Number of cycles to failure at level load; Number the load; is the Boltzmann parameter; S32: For the aviation electromechanical and hydraulic product tree constructed in step S31, determine the corresponding wear-out failure mechanism model for each node unit of the aviation electromechanical and hydraulic product tree, including: fatigue failure model , wear failure model and aging failure models ; 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 product in step S11 and the stress spectrum of the aviation electromechanical and hydraulic product obtained in step S22, at a load level of When , calculate the minimum agreed level unit failure time of aviation electromechanical and hydraulic products for: ； in, The minimum agreed hierarchical unit failure time for aviation electromechanical and hydraulic products; is the single load history time; 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 electro-hydraulic product 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, characterized in that: The one-dimensional performance control model of the electromechanical and hydraulic product in step S11 is obtained during the product design phase based on power bond graph theory, Modelica language, and VHDL language modeling. The loads on each lowest agreed level of the aviation electromechanical and hydraulic product 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 of the product, including relative motion relationship, power transfer relationship and constraint relationship, and provides a basis for determining the load type of the lowest agreed level unit. It 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, characterized in that: In step S12, the aircraft electromechanical and hydraulic products are subjected to structural decomposition, load analysis, mechanism determination, and mechanism merging, specifically: S121: Structural decomposition requires clarifying the product's composition, working principle, and characteristics. The product's structural decomposition should be divided into the initial agreed level, agreed level, and lowest agreed level. A product agreed level diagram or table should be drawn to determine the lowest agreed level unit for mechanism analysis. S122: Load analysis is based on the product's mission profile and life cycle load spectrum, combined with the product's lowest agreed levels and the motion and constraint relationships between components. It analyzes and determines all load types and modes of action to which each lowest agreed level is subjected throughout its life cycle. Specifically, it includes: operational loads and environmental loads. The operational loads include load force, speed, stroke, medium pressure, and medium temperature. The environmental loads include vibration and ambient temperature. S123: Failure mechanism determination: Based on the structural decomposition and load analysis, for each lowest agreed level unit, analyze and determine all 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 occur and lead to performance degradation; the wear mechanism is determined based on the principle that 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; S124: Mechanism merging is performed when the load causes the same mechanism or the unit interaction causes the same mechanism. 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 the electromechanical fluid of aviation electromechanical fluid products, the mission profile and workload spectrum of the product are used as input. Through electromechanical fluid field performance simulation, the workload and environmental load spectrum of each lowest agreed level that needs to be simulated throughout the entire life cycle are obtained; The input loads of electromechanical and hydraulic products are 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 into a one-dimensional control performance model for load simulation analysis. This obtains the load profiles of each lowest agreed level under the product's operating profile, providing 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: Fatigue failure model in step S32 , wear failure model and aging failure models , specifically: The fatigue failure model According to the characteristics of electromechanical and hydraulic products and engineering applications, the stress method based on the material SN curve is: ； in, Output results for fatigue failure models; is the number of cycles; is the first parameter of the material; is the second parameter of the material; The wear failure model Specifically, the adhesive wear model: ； in, Output for the wear failure model; is the wear coefficient; For the wear stroke; is the surface hardness of the material; The insulation aging model in the aging failure model is: ； in, is the average insulation aging life; are material parameters related to insulation; is the insulation aging model parameter; The sealing aging model in the aging failure model is: ； in, is the aging reaction rate, and its reciprocal is the aging life; is the sealing parameter; is the material activation energy parameter; is the Boltzmann parameter; is the sealing temperature parameter.

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