108 results about "Vibration fatigue" patented technology

The present invention relates to the technical field of mechanical property testing and characterization. Disclosed are a method and apparatus for calculating a crack propagation life of an engine structure in vibration fatigue, which method and apparatus aim to obtain reliable fracture mechanics parameters and a crack propagation rate curve and provide an accurately quantified crack propagation life, so as to provide methodological guidance for the life assessment of reusable engines. The calculation method comprises: acquiring a time-domain random stress spectrum of stress responses in an assessment section in a finite element model of an engine structure; on the basis of the time-domain random stress spectrum, performing finite element analysis processing on a crack model of the engine structure, so as to determine fracture mechanics parameters of a cracked structure; performing a vibration fatigue performance test on a crack propagation rate model, which is set up according to a preset crack propagation mode, and determining, by using parameter identification, a target parameter value corresponding to the crack propagation rate model; and in combination with the parameter value corresponding to the crack propagation rate model and a preset critical crack length value, performing crack propagation life calculation, so as to obtain a target crack propagation life.

The invention provides a method for monitoring cracks in a high-pressure vibration state of a wind tunnel in real time, and belongs to the technical field of wind tunnels. A piezoelectric ceramic sensor array is arranged on the wall surface of the wind tunnel, a vibration fatigue matrix and a structure resonance matrix are established, and a self-adaptive filtering algorithm is adopted to preprocess sensor signals; establishing a vibration coupling equation set to extract crack characteristic parameters, constructing a dynamic threshold discrimination matrix and a risk assessment matrix, utilizing a multi-sensor data fusion algorithm to accurately position crack positions and sizes, calculating risk levels according to a crack risk assessment index equation, and performing three-level safety discrimination. A complete crack real-time monitoring and risk assessment system in the high-pressure vibration environment is formed, and the technical problems that in the prior art, crack monitoring precision is low in the high-pressure vibration environment, and real-time risk assessment cannot be achieved are solved.

The invention discloses a vibration fatigue life prediction method and system based on a working condition adaptive spectrum. According to the method, load information of a target structure under various service conditions is obtained, and frequency domain load descriptions corresponding to different working conditions are subjected to weighted fusion according to working condition weights, so that a working condition adaptive load spectrum capable of reflecting real service characteristics is constructed; on the basis, frequency domain stress response of the structure under the random vibration condition is obtained in combination with a structural dynamics analysis model, equivalent stress description of dominant fatigue damage is further determined through a multi-axis equivalent criterion, and fatigue damage distribution is calculated through a frequency domain fatigue analysis method; and finally, predicting the vibration fatigue life of the structure in combination with a material fatigue performance curve and an environment-related performance correction relation. Compared with the prior art, the method has the advantages that the multi-working-condition load superposition effect and the service environment influence can be effectively considered, and the accuracy and engineering applicability of vibration fatigue life prediction are improved.

The invention provides a stay wire tower stay cable vortex-induced vibration fatigue life prediction method and system, and relates to the technical field of power transmission line towers, and the method comprises the steps: obtaining sensing detection parameters corresponding to a to-be-detected stay wire tower; the sensing detection parameters comprise sag, sag maximum position stress, specific load, span, altitude difference angle, temperature expansion coefficient, elastic modulus and meteorological parameters; fusing tension data obtained through sensing detection parameters with tension data estimated through a structural mechanical model by adopting a Kalman filtering algorithm, and determining a tension time history of the stay wire structure within a preset time range, determining natural vibration frequencies of the stay wire structure at different moments within the preset time range by combining the wire length and the quality of the stay wire structure; and determining a target oscillation-starting wind speed range by using a first mapping relation between the natural vibration frequency and the oscillation-starting wind speed of the stay wire structure, and determining a life prediction result of the stay wire structure in combination with wind speed distribution and the number of fatigue cycles in the preset time range.

The invention discloses a bogie component vibration fatigue life prediction method considering load periodic evolution, and aims to solve the technical problems that an existing model is coupled in function and low in prediction precision, and a prediction result is a single determined value and cannot meet risk assessment requirements. Comprising the following steps: a) acquiring a historical power spectral density sequence; b) inputting the historical power spectral density sequence into a hybrid degradation prediction model, and predicting axle box vibration power spectral density under any running mileage in the future; c) inputting the axle box vibration power spectral density predicted in the step b) into a nonlinear transfer function model based on artificial intelligence, and calculating the stress power spectral density of the key position of the bogie; d) dynamically determining an optimal calculation mileage step length by the decision-making type artificial intelligence model, and then calculating future prediction fatigue damage; and e) calculating generated actual fatigue damage according to historical monitoring data, and outputting probability distribution of the residual fatigue life of the bogie by integrating future predicted fatigue damage.

The invention discloses an ultrafast laser strengthening method for improving the vibration fatigue life of titanium alloy, and belongs to the technical field of metal material surface strengthening. The method comprises the following steps: S1, carrying out surface cleaning treatment on a titanium alloy material; s2, carrying out laser strengthening treatment on the surface of the metal material by using ultrafast laser; s3, ABAQUS software is adopted to simulate stress and displacement of the titanium alloy simulation part under the first-order vibration frequency; s4, carrying out a vibration fatigue test, and comparing the vibration fatigue life of the titanium alloy simulation part before and after reinforcement; according to the ultrafast laser strengthening method, ultrahigh-pressure shock wave pressure is generated on the surface of the metal material through induction of ultrafast laser, then a gradient residual compressive stress layer, finer crystal grains and higher dislocation density are formed on the near surface of the metal material, and the vibration fatigue life is prolonged by inhibiting crack initiation; the ultrafast laser strengthening method is high in feasibility and good in strengthening effect and has high application and popularization value.

The invention relates to the technical field of vehicle assembly vibration fatigue tests, in particular to a road load spectrum-based accelerated random vibration spectrum determination method, which comprises the following steps of: selecting i-circle data of each characteristic road surface under full-load, half-load and no-load working conditions as original data of accelerated random vibration spectrum calculation; calculating an impact response spectrum and a fatigue damage spectrum of the i-circle data of each characteristic pavement; respectively accumulating the fatigue damage spectrum statistical values of the three working conditions; packaging the maximum values of the impact response spectrums under the three working conditions; according to a fatigue damage accumulation theory, calculating a fatigue damage spectrum of the total target mileage according to the number of cycles of three working conditions; packaging the maximum value of the impact response spectrum of the whole circle of characteristic pavement under the three working conditions to obtain the maximum value of the overall target mileage impact response spectrum; synthesizing an accelerated random vibration spectrum by using the fatigue damage spectrum of the total target mileage according to a damage equivalence principle; and finally, carrying out ERS calculation on the generated accelerated random vibration spectrum, and checking the correctness and rationality of the accelerated random vibration spectrum.

The invention discloses a vibration fatigue risk assessment method and device for an axial flow blade, a medium and equipment, and relates to the technical field of axial flow compressors, and the method comprises the steps: creating a blade finite element model of a target axial flow blade, and respectively applying a rotating speed and a steady-state aerodynamic load corresponding to each interference working condition point on the target axial flow blade to the blade finite element model, pre-stress modal analysis is carried out, and a finite element modal analysis result corresponding to each interference working condition point is obtained; calculating an allowable modal force of the target axial flow blade under each interference working condition point based on a finite element modal analysis result; calculating a sorting factor of each interference working condition point according to the allowable modal force; and carrying out danger degree sorting on the plurality of interference working condition points on the target axial flow blade based on the sorting factor, and sequentially carrying out vibration fatigue risk assessment on the plurality of interference working condition points according to a descending order of the danger degrees. The vibration fatigue safety analysis period can be shortened, and the analysis efficiency can be improved.

This utility model discloses a forced vibration fatigue testing device for thin metal sheets, belonging to the field of fatigue life testing technology for thin metal sheet materials. It addresses the problems of low vibration frequency, poor adaptability, and bulky structure in traditional testing devices. The device includes a trapezoidal impact platform base, a housing, a modular support frame, and a drive and detection mechanism. The support frame consists of an experimental support, a test piece platform, and limiting blocks, achieving rapid positioning and height adjustment of the test piece via bolts. The drive and detection mechanism includes symmetrically distributed motor and encoder assemblies. The motor drives the roller shaft via a coupling, causing the rollers to rotate at high frequency. The encoder records data in real time and provides feedback via a touchscreen. The trapezoidal base incorporates a shock-absorbing layer to improve stability, the modular structure reduces structural weight, it is adaptable to thin metal sheets of varying thicknesses, and the integrated touchscreen interface provides convenient operation. This device is suitable for high-precision fatigue life testing of ultra-thin materials such as aerospace flexible components.

This invention provides a novel vibration fatigue testing method for gas turbine blades. Addressing the problems of large specimen wear, long testing time, and limited results associated with traditional step-and-step stress loading methods for obtaining blade fatigue limits, this invention excites blade resonance on an electromagnetic vibration table using novel step-and-step stress loading techniques on identical blade specimens. While retaining the step-and-step matching standard, when limited test data cannot meet the matching requirements, a stress "concession" method is rationally applied based on the turbine blade structure and fatigue strength level to eliminate test data with significant stress deviations, thereby obtaining the median fatigue strength of blades from the same batch. This invention makes stress matching faster and more flexible, requiring only 2-3 stress levels to achieve a test fitting result with a confidence level of over 95%, demonstrating high accuracy. This method is applicable to fatigue limit tests of all gas turbine blades.

The invention discloses an overhead line system electric connecting line vibration fatigue test device, which relates to the technical field of railway overhead line systems, and comprises a high-speed railway overhead line system simulation support and a reciprocating lifting mechanism, and an electric connecting line is connected between a carrier cable and a contact line on the high-speed railway overhead line system simulation support. A reciprocating lifting mechanism is arranged below the connecting position of the electric connecting wire and the contact wire, a bearing block is arranged at the top of the reciprocating lifting mechanism, and the bearing block can make contact with or be away from the connecting position under the action of the reciprocating lifting mechanism. The high-speed railway overhead line system simulation support is used for simulating the real working condition of the electric connecting line, the reciprocating lifting mechanism is used for simulating the working condition of the locomotive pantograph running on the line, the corresponding fatigue life test can be carried out on the service state of the electric connecting line closer to the actual working condition, more accurate experimental data can be obtained, and the test efficiency is improved. And the service life of the electric connecting wire in the corresponding service environment can be accurately predicted.

The invention provides an underwater vehicle equipment support random vibration fatigue simulation prediction method and system. The method comprises the steps that a finite element model is constructed based on the actual installation postures of a halogen lamp support and a halogen lamp in the transportation process; analyzing the modal distribution of the halogen lamp bracket in the installation state, identifying the weak link of the key modal, and analyzing the coupling condition of the modal frequency and the PSD excitation frequency; carrying out random vibration analysis, and determining a stress frequency response function and a stress root mean square RMS stress of the key position; and based on a random vibration analysis result, predicting the fatigue life of the halogen lamp bracket and reproducing a fracture phenomenon. And optimizing the support structure through a strategy of combining free shape optimization and multi-model optimization. According to the method, the service life of the halogen lamp bracket is predicted more accurately, the halogen lamp bracket is optimized, the modal frequency of the bracket is improved, the stress amplitude is reduced, and the fatigue life is prolonged.

The invention discloses a cable bridge vibration fatigue testing device and method, and relates to the technical field of testing devices.The cable bridge vibration fatigue testing device comprises a supporting frame and a placing assembly; a mounting hole is formed in the lower side of the supporting frame, and an impact assembly is mounted on the right side of the supporting frame; the placing assembly comprises a placing frame, a first spring, a second spring and a vibration motor; the cable bridge vibration fatigue test method comprises the following steps: S1, fixing and initializing a sample: horizontally placing the cable bridge sample in a placing frame, starting a first motor of a clamping assembly to drive a bidirectional screw rod to rotate, and driving clamping plates on two sides to synchronously and oppositely move until a rubber plate is tightly attached to the side surface of the sample to complete transverse clamping, the multi-axis composite vibration in an actual scene can be reproduced, the vibration intensity can be rapidly adjusted, and the cable bridge can be prevented from slipping during testing.

The invention discloses a vibration fatigue finite element analysis method for a vertical low-temperature heat-insulation gas cylinder system. The method comprises the following steps: constructing a three-dimensional model of the vertical low-temperature heat-insulation gas cylinder system by utilizing modeling software; respectively importing the three-dimensional models of the vertical low-temperature heat-insulation gas cylinder system into ANSYS finite element analysis software, setting material attributes according to reality, and performing contact and grid division; setting load and constraint according to the actual vibration test working condition, and calculating the inherent frequency of the vertical low-temperature heat-insulation gas cylinder system in the ANSYS modal analysis module; converting the actually measured pavement unevenness power spectral density or the national standard pavement unevenness power spectral density into a random vibration load, and calculating a random vibration dynamic response by combining the inherent frequency obtained by modal analysis; the random vibration fatigue life of the low-temperature heat-insulation gas cylinder system is determined by combining an S-N curve of a material and a fatigue failure criterion, and theoretical guidance is provided for vibration characteristic research and safety application of the vertical low-temperature heat-insulation gas cylinder system.

The application provides a tension-compression-bending vibration fatigue and force-position characteristic integrated testing device and system of a micro elastic element, and belongs to the technical field of micro elastic element testing. The device and system solve the problems of single function of the existing elastic element testing equipment, dependence of vibration fatigue testing and force-position characteristic testing on independent professional systems, and difficulty in adapting to millimeter-level micro elastic elements and difficulty in realizing multi-dimensional deformation loading. The device and system comprise a Y-direction displacement platform fixed on a base, an X-direction displacement platform provided with an adapter platform between the Y-direction displacement platform, a force sensor provided on the base along an axis parallel to the Y-direction displacement platform and connected with a displacement amplification mechanism, and a vibration exciter fixed on the base and connected with the displacement amplification mechanism. One end of a test spring is connected to the X-direction displacement platform, and the other end of the test spring is provided with two stations. A first station is connected with the force sensor, a second station is connected with the displacement amplification mechanism, and a laser displacement sensor detects the displacement of the displacement amplification mechanism.

The invention relates to the technical field of cable polymer sheaths, in particular to a polymer sheath material for a multifunctional speed sensor cable of a high-speed motor train unit, which is prepared from the following raw materials in parts by weight: basic resin; reinforcing the modified material; a functional additive; an environmental stabilizer; a processing aid; the environment stabilizer is composed of a composite antioxidant, an ultraviolet light absorber and an ozone stabilizer. Through basic resin composite modification and functional component synergistic optimization, in combination with nano silicon nitride and aramid chopped fiber reinforcement, and in combination with functional additives such as the halogen-free flame retardant and the carbon nanotubes and a special environment stabilizer, the comprehensive performance of the material is improved, extremely cold and high-temperature part radiation can be resisted, and the service life of the material is prolonged. The volume change rate is less than or equal to 5% after the cable is soaked in special lubricating oil for the motor train unit for 72 hours, the flame retardant property is higher, meanwhile, the cable is halogen-free and environment-friendly, the service life of the sensor cable is remarkably prolonged, and stable transmission of speed signals is guaranteed.

The invention provides a gas turbine compressor blade service life evaluation method based on high-cycle fatigue characteristics, and aims to solve the problem that fatigue tests under pure simulation and laboratory conditions cannot be effectively combined to meet the requirement of gas turbine blade type core component service life evaluation. According to the method, the strength condition and the vibration condition of the blade are determined through finite element analysis, then the stable attenuation law of the fatigue strength of the blade is obtained by actually measuring the vibration stress and the fatigue limit values of the blade in different use time periods, and the service life of the gas turbine compressor blade is comprehensively evaluated by taking the high-cycle vibration fatigue reserve as the standard. The method is not limited to a ship gas turbine compressor, is also suitable for effective evaluation of the service life of the moving blades of an industrial gas turbine and an aero-engine compressor, and can provide a fatigue reliability design direction for a new model.

This invention discloses a vehicle electrical safety monitoring system for vehicle stoppage, relating to the field of new energy vehicle control technology. It includes an intelligent sensing layer, a digital twin decision-making layer, a hierarchical execution layer, and a safety escape layer. The intelligent sensing layer comprises a multimodal sensor array for real-time acquisition of physical, chemical, and environmental parameters of the vehicle's electrical system. This invention constructs a high-precision three-dimensional model including the battery compartment geometry and wiring harness layout, embedding an electrolyte leakage model and a wiring harness aging model. The former simulates diffusion paths based on fluid dynamics and predicts short-circuit risks, while the latter combines vibration fatigue and insulation material aging analysis to achieve fault evolution prediction based on physical mechanisms. This overcomes the lag of traditional threshold alarms. A dynamic threshold table is generated by combining ambient temperature, state of charge, and historical fault data, solving the problem that traditional fixed thresholds cannot adapt to complex operating conditions and reducing false alarm and false negative rates.

This invention discloses a non-contact force-vibration coupled loading material fatigue testing device and method, belonging to the field of material fatigue testing technology. It includes a support frame with a horizontal adjustment component mounted on it, and further includes: a first loading component mounted on the adjustment end of the adjustment component, comprising an electromagnetic drive power supply, an annular bearing disk, and several electromagnet components. The annular bearing disk is mounted on the adjustment end of the adjustment component, and the several electromagnet components are arranged in a circular array on one side of the annular bearing disk, with each electromagnet component sliding along the diameter of the annular bearing disk; and a second loading component, configured as a vibration fatigue machine mounted on the top surface of the support frame. The top of the vibration fatigue machine holds the workpiece to be tested via a clamping component, and the workpiece to be tested coincides with the axis of the annular bearing disk. Through testing, this invention effectively solves the technical problem of traditional vibration fatigue testing's inability to couple external loads, achieving accurate loading and performance testing of the specimen under highly simulated working conditions.

The application relates to the diesel engine technical field, in particular to a diesel engine heat dissipation damping device and a using method thereof, which comprises a damping protection box, a heat dissipation mechanism is fixedly arranged on the outer side of the damping protection box, balance guide rods are symmetrically arranged in the damping protection box, support mechanisms are symmetrically arranged on the balance guide rods in a sliding mode, and a diesel engine is arranged on the support mechanisms. The rubidium magnet on the buffer sliding block can be used for horizontal damping, the buffer clamping base can be used for vertical damping of the diesel engine, parts are prevented from being damaged due to long-term vibration fatigue, the service life of the diesel engine is greatly prolonged, the diesel engine is suspended in the damping protection box, the water tank, the water conveying main pipe and the water conveying branch pipe are communicated with each other and can form circulating water flow, and the semiconductor refrigerating sheet is used for heat dissipation of the water tank, so that the heat dissipation efficiency is improved.

The invention belongs to the technical field of aero-engines, and particularly relates to a double-wall single crystal blade cooling unit flat plate vibration fatigue simulation piece and device, and the piece comprises an examination section, a clamping section located at one side of the examination section, and a frequency modulation section located at the other side of the examination section. The examination section is provided with an air film hole, a streaming column and an impact hole which are used for simulating a target blade, the clamping section is provided with a mounting hole, and the frequency modulation section is used for adjusting the inherent frequency of a simulation piece to be the same as the inherent frequency of the target blade; the electromagnetic vibration table is used as an excitation source; the clamp is used for clamping the clamping section of the simulation piece and is fixed on the electromagnetic vibration table; the heating system is used for heating the simulation piece examination section to a preset temperature; the displacement measurement system is used for measuring the vibration frequency of the simulation piece; and the thermocouple is used for measuring the temperature of the simulation piece examination section. In the initial stage of design, optimization of various double-wall cooling units is achieved, the design quality of the double-wall blade is improved, and the effect of replacing a real blade vibration fatigue test is achieved to a certain extent.

The invention belongs to the technical field of spacer test, and particularly relates to a spacer gripper impact vibration test fatigue machine and a test method thereof.The spacer gripper impact vibration test fatigue machine comprises a test bed, a first simulation piece is arranged in the middle of the upper portion of the test bed, and second simulation pieces are arranged on the two sides of the first simulation piece; spacer test pieces are arranged between the first simulation piece and the second simulation pieces on the two sides. The first simulation piece is used for simulating the influence on the spacer test piece when the magnitude and the direction of wind power are different in the actual use process, and the second simulation piece is used for simulating the influence on the spacer test piece by a transverse and torsion combined load; and the first simulation assembly is used for driving the first simulation component to adjust the vibration amplitude. Through cooperation of the first simulation assembly and the second simulation assembly, the vibration amplitude and the vibration steepness can be adjusted at the same time, a full wind power scene is covered, and the problem that existing equipment can only simulate a fixed vibration mode is solved.

This utility model relates to a pipe clamp gasket structure for reducing internal stress in pipes during multi-pipe installations. It includes a pipe clamp, which consists of an upper metal cover plate, a lower metal cover plate, and a pipe clamp gasket. The upper and lower metal cover plates are fixed to the pipe clamp gasket using bolts, nuts, or other fasteners. The advantages of this utility model are that by using nylon with high external hardness to support the pipes and suppress pipe vibration, while the internal low-hardness rubber effectively reduces stress between the pipe clamp and the pipe during dynamic vibrations during installation. This reduces the risk of vibration fatigue and durability failure.

1. The name of the design product: three-dimensional deformation measurement sensor. 2. The use of the design product: suitable for displacement and strain online measurement of various material deformation and structural deformation, and its small and integrated design greatly improves the usability of visual measurement instruments. High-precision measurement of key mechanical parameters such as three-dimensional displacement, full-field strain, dynamic vibration, fatigue damage and fracture behavior of materials and structures can be achieved. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view 1.

The invention discloses a method for optimizing the random vibration fatigue life of a laminated welding spot, which comprises the following steps of: establishing a finite element simulation analysis model of the laminated welding spot based on ANSYA software, performing random vibration mode analysis and stress-strain analysis on the model, predicting the fatigue life of the laminated welding spot, determining factors and level values which influence the life of the laminated welding spot, and optimizing the fatigue life of the laminated welding spot. 9 groups of different parameter level combinations are designed by using an orthogonal test method, the vibration fatigue life of the 9 groups of laminated welding spots is predicted, range analysis is carried out, the optimal level combination with the maximum life is obtained, simulation verification is carried out, and the optimization method is simple and obvious in effect, and has certain reference significance for fatigue life optimization of other types of welding spots.

The present application relates to a kind of heat insulation platform, it includes heat insulation plate, first connecting piece and second connecting piece.Heat insulation plate is used to be arranged between vibration table group and heating plate, first connecting piece is used to connect heat insulation plate and vibration table group, and the length of first connecting piece is less than the thickness of heat insulation plate when being contained in heat insulation plate;Second connecting piece is spaced apart from first connecting piece, and second connecting piece is used to connect heat insulation plate and heating plate, and the length of second connecting piece is less than the thickness of heat insulation plate when being contained in heat insulation plate.When long time high temperature condition vibration fatigue test experiment is carried out to experimental sample, since first connecting piece does not directly contact heating plate, second connecting piece does not directly contact vibration table group, the heat generated by heating plate is not easily directly transmitted to vibration table group through first connecting piece or second connecting piece.Therefore, the temperature of vibration table group is low, and damage is not easily occurred;And the vibration signal transmitted to experimental sample through heat insulation plate is more accurate, and the experimental data obtained ultimately is also more accurate.

This application belongs to the technical field of vibration fatigue test design for aircraft panel structures, specifically relating to an in-plane prestressed loading vibration fatigue test system for aircraft panel structures. The system includes a vibration support fixture and a prestressed loading fixture connected to the panel structure. The prestressed loading fixture is used to apply in-plane prestress to the panel structure, including tensile prestress and compressive prestress. The vibration support fixture is used to support the panel structure, the prestressed loading fixture, and to connect to a vibration table for vibration loading of the panel structure.

The invention belongs to the technical field of aircraft fatigue life design, and particularly relates to an equal stress amplitude vibration fatigue S-N curve determination method and device. The method comprises the following steps: carrying out random vibration response analysis on a structural dynamic finite element model of a cantilever beam with one end clamped and supported, and obtaining a vibration stress power spectral density function and a vibration stress root-mean-square; determining a k-order moment of the vibration stress power spectrum density function; determining a coefficient value of a vibration stress amplitude probability density function formula according to the k-order moment; determining a constant C of the equal stress amplitude vibration fatigue S-N curve; determining a stress amplitude S corresponding to the specified cycle index N according to the constant C; and determining a vibration fatigue SRMS-N curve parallel to the random stress amplitude and a curve passing through the corresponding coordinate points of the cycle index N and the stress amplitude S as an equal stress amplitude vibration fatigue S-N curve. The equal stress amplitude vibration fatigue S-N curve constructed by the invention improves the efficiency of evaluating the vibration fatigue life of the structure.

The application provides a novel vibration fatigue test method for a gas turbine compressor blade, which uses a material fatigue test statistical analysis method, uses a novel stress loading method on a blade test piece to excite blade resonance in a wide stress level coverage and a large number of stress level series, reasonably corrects stress levels according to a stress 'yield' principle, fills in the missing test stress sub-samples, reduces the dispersion of test data, and makes the stress sub-sample pairing more flexible and fast, and then obtains the median fatigue strength of the same batch of blades. The method can greatly save test cost, save test time, and avoid problems such as high test data variation coefficient or low confidence level caused by the structure itself characteristics or processing process error.

The invention provides a wooden door structural strength simulation analysis and optimization method and system. According to the method, a defect distribution diagram is generated by combining wavelet multi-resolution analysis and wooden door pore data, a parameterized model is established in combination with finite element simulation, and a stress propagation path is extracted through transient dynamic analysis after a vibration load is applied; identifying stress space aggregation points through Fourier frequency domain decomposition, and synchronously establishing a material expansion and contraction model under temperature and humidity circulation; the expansion and shrinkage deformation quantity and the stress gathering points are superposed to generate composite load weak area distribution, a geometric model is reconstructed based on variable density topological optimization, and the material density is adjusted according to a defect graph and a weak area; and finally, optimizing local rigidity configuration, so that the inherent frequency of the door body avoids a switch excitation frequency band, and obtaining a high-reliability residence wooden door structure. The vibration fatigue resistance and environmental deformation resistance of the wooden door are remarkably improved, the service life is prolonged, and noise is reduced.