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372 results about "Structural dynamics" patented technology

Structural dynamics, is a type of structural analysis which covers the behavior of a structure subjected to dynamic (actions having high acceleration) loading. Dynamic loads include people, wind, waves, traffic, earthquakes, and blasts. Any structure can be subjected to dynamic loading. Dynamic analysis can be used to find dynamic displacements, time history, and modal analysis.

Building dynamic structure health monitoring method

The invention provides a building dynamic structure health monitoring method. The method comprises the steps that original data of a multi-mode sensor is acquired and preprocessed; constructing topology sensing network representation reflecting the spatial distribution and structure connection relation of the sensors; extracting multiple spatio-temporal scale features; local-to-global structure state mapping is realized by using a recurrence plot evolution predictor; integrating structural dynamics knowledge into the neural network model to perform physical constraint correction; and constructing a multi-dimensional health index set and outputting damage probability evaluation. According to the invention, accurate mapping from the local dense monitoring area to the global structure state under the non-uniformly distributed sensor network is realized, and the accuracy and reliability of structure health monitoring are improved.
Owner:JIANGSU TESTING CENT FOR QUALITY OF CONSTR ENG

Building structure anti-seismic performance monitoring method and system

The invention relates to the field of building structure safety detection, and discloses a building structure anti-seismic performance monitoring method and system. The method comprises the following steps: acquiring multi-source response data such as acceleration, displacement, strain and inclination angle; obtaining a structure standard response based on wavelet denoising and standardization processing; adopting a multi-order modal recognition algorithm to extract structural dynamic characteristic parameters; performing structural damage evaluation based on the modal change index, and combining the yield strength, the load index and the displacement margin to calculate the residual bearing capacity of the structure; and finally, outputting an anti-seismic grade early warning signal. The system comprises a structure response acquisition module, a modal identification and damage evaluation module and a residual bearing capacity calculation and early warning module. According to the method, real-time quantitative analysis of the performance of the structure under the earthquake or load effect can be achieved, the evaluation precision is high, the applicability is high, and the wide engineering popularization value is achieved.
Owner:PINGMEI SHENMA CONSTR GRP FIRST CONSTR ENG CO LTD +1

Method and system for designing three-section combined structure of ultrahigh wind power generation tower drum

The invention relates to the technical field of data processing, and discloses a three-section combined structure design method and system for an ultrahigh wind power generation tower. The method comprises the following steps: analyzing wind speed distribution data through a wind load-structural dynamics-material mechanics coupling algorithm to obtain rigidity distribution functions and frequency avoidance constraints of three functional partitions, performing multi-objective optimization on a lower truss section to obtain geometric parameter configuration, performing fluid-solid coupling vibration control design on a middle multi-edge transition section, and performing multi-functional partition design on the middle multi-edge transition section. And aeroelastic instability prevention and control design is carried out on the upper cylindrical section, integrated dynamic coordination processing is carried out on the three-section structure, multi-working-condition verification is carried out through a large eddy simulation-finite element coupling verification algorithm, and target design parameters are obtained. The wind power tower drum solves the technical problems that the existing wind power tower drum technology cannot break through the limitation of the 360-meter super height and cannot meet the requirements of structural safety, economical efficiency and constructability at the same time.
Owner:ZHONGCHENG ELECTRICAL EQUIPMENT (SHANDONG) CO LTD

Fixed offshore wind turbine structure dynamic response obtaining method

The invention discloses a structural dynamic response obtaining method for a fixed offshore wind turbine. The method comprises the following steps: establishing an initial finite element model according to related model data of a fixed offshore wind turbine to be tested, correcting the initial finite element model in combination with obtained actually measured modal parameters, and solving a vibration mode function based on the corrected finite element model; solving kinetic energy and potential energy of the to-be-tested wind driven generator structure; and according to the obtained structural kinetic energy and potential energy, a mass matrix, a stiffness matrix and a damping matrix are constructed based on an Euler-Lagrange equation and a basic kinetic equation, so that a dimensionality-reduced structural kinetic model of the offshore wind turbine is established, an inherent frequency value is obtained through solving, and the dynamic response is obtained. The method effectively overcomes the defects that a model is established depending on finite element software to solve the dynamic response in the prior art, and has the advantages that the modeling process is simple, the solving time is short, multi-field coupling load application can be met, and the control technology is easy to implement.
Owner:XIAN TECH UNIV

Software operation and maintenance method and system and storage medium

The invention relates to the technical field of data mining, in particular to a software operation and maintenance method and system. The method comprises the following steps: acquiring engineering simulation heterogeneous hardware data, and performing multi-physics field coupling tensor compression to obtain a multi-physics field topology snapshot; finite element grid nonlinear constraint is executed based on the multi-physics field topology snapshot, and a nonlinear contact strategy tensor is obtained; according to a non-linear contact strategy tensor coding structure dynamics intelligent contract, simulation software dynamics credibility verification is carried out, and a dynamics credible chain is obtained; constructing a hydrodynamic vortex model based on the dynamic trusted chain, and performing boundary layer separation simulation flow optimization on the hydrodynamic vortex model to obtain a vortex flow field map; performing explicit dynamic explicit integration on the vortex flow field atlas to obtain a convergence optimization field; and performing phase field damage evolution according to the convergence optimization field to obtain a multi-physics field evolution twinborn body, and deploying the multi-physics field evolution twinborn body. The method can effectively improve the utilization rate of software computing resources.
Owner:GRANDPA DOES NOT MAKE TEA (HUBEI) TECHNOLOGY SERVICE CO LTD

Structure optimization design method based on particle swarm optimization

The invention discloses a structure optimization design method based on a particle swarm optimization algorithm, aiming at a super high-rise building, an initial structure parameter matrix is generated by establishing an optimization model, setting a target function and taking structure layer displacement, an inter-layer displacement angle and top layer peak resultant acceleration as constraint conditions; a wind vibration response characteristic matrix is obtained by adopting a frequency domain calculation method in combination with structural dynamic characteristics and a wind tunnel test result, and an equivalent static wind load matrix and an acceleration response matrix are calculated. A combined algorithm of an optimization criterion method and a particle swarm algorithm is used for performing multiple iterations, wind load and acceleration response data are recalculated by initializing and updating related parameters of a particle swarm, calculating a fitness value, iteratively updating a position and a speed matrix, and finally an optimal solution matrix is output according to convergence judgment. Therefore, a final design scheme of the structure is determined, and comprehensive optimization of wind resistance and economic benefits of the structure is realized.
Owner:NO 63921 UNIT OF PLA

Large-span roof structure wind-induced response fast algorithm considering high-order modal quasi-static response

The invention discloses a large-span roof structure wind-induced response fast algorithm considering high-order modal quasi-static response, and the algorithm comprises the following steps: S11, building a finite element model of a large-span roof structure, and determining the modal damping ratio of the large-span roof structure according to the design condition, so as to obtain the structural dynamic characteristics of the large-span roof structure; step S12, determining a random wind load acting on the large-span roof structure through a wind tunnel test, and calculating a wind load Fourier transform function of a truncation function corresponding to the random wind load; step S13, according to the dynamic characteristics of the structure and the wind load Fourier transform function, performing calculation by adopting a modal acceleration method, obtaining a Fourier transform function of the structure displacement response; and S14, according to the Fourier transform function of the structure displacement response, performing power spectral density estimation by adopting a periodogram method to obtain a power spectral density matrix of the structure displacement response, and performing integration on the power spectral density matrix of the structure displacement response to obtain a displacement response root-mean-square of the large-span roof structure. According to the method, quasi-static response of a high-order mode is considered, better convergence is achieved compared with a traditional method, and under the condition of the same precision, calculation time and memory occupation are relatively small.
Owner:CHINA CONSTR SECOND ENG BUREAU LTD +1

Acoustic black hole beam dynamics analysis method

The invention discloses an acoustic black hole beam dynamic analysis method, which relates to the technical field of structural dynamics and acoustics, and comprises the following steps: step 1, establishing an acoustic black hole beam theoretical model; 2, according to the Euler-Bernoulli beam theory, the displacement field components of the moment t and the acoustic black hole beam point x can be expressed as # imgabs0 #; and 3, the NURBS function is used for describing the geometry and displacement of the acoustic black hole beam. According to the acoustic black hole beam vibration characteristic and energy transfer analysis method based on isogeometric analysis and the finite element thought, the calculation efficiency is improved while the geometric accuracy is guaranteed, a powerful tool is provided for optimization design and performance evaluation of an acoustic black hole structure, and through deep analysis of energy transfer and distribution characteristics, the method has the advantages that the calculation efficiency is improved; the mechanism of the acoustic black hole effect can be further revealed, and a new thought and method are provided for development of the vibration and noise reduction technology.
Owner:GUIZHOU UNIV

Train-bridge-soil body-shield tunnel system coupling dynamic analysis method

The invention belongs to the technical field of shield construction, and aims to solve the problem that the spatial coupling effect between an overground subsystem and an underground subsystem cannot be considered because the numerical analysis of a high-speed railway bridge under a shield tunnel mode is based on a local model at present. The train-bridge-soil body-shield tunnel system coupling dynamic analysis method comprises the following steps that a bridge-track subsystem is established, and meanwhile a vehicle subsystem is established; a soil body-tunnel subsystem is established; the bridge-track subsystem and the vehicle subsystem are connected through the wheel-rail contact relation as a link, meanwhile, the bridge-track subsystem and the soil body-tunnel subsystem are connected through the link as a pile-soil interaction relation, and a coupling model of a train-bridge-soil body-shield tunnel system is obtained; and performing coupling dynamic analysis on the model based on an asynchronous length method and a time domain integration algorithm. The dynamic interaction of the train, the track, the bridge and the shield tunnel can be considered at the same time, and more accurate structural dynamic response can be obtained.
Owner:CENT SOUTH UNIV +3

Structural dynamic characteristic analysis and optimization method and device

The embodiment of the invention provides a structural dynamic characteristic analysis and optimization method and device, and the method comprises the steps: obtaining an acceleration record of a strong vibration monitoring array, carrying out the data preprocessing, obtaining a preprocessed acceleration time history, carrying out the structural response analysis, and obtaining a structural response analysis result, performing modal identification technology analysis by using a time peak value pickup method and a frequency domain random subspace method to obtain a mutually verified structure first-order period, and obtaining a verified modal identification method; based on the periodic empirical formula, performing first-order periodic empirical formula fitting analysis on the typical super high-rise building array, and revising the first-order periodic empirical formula of the super high-rise building; and obtaining the damping ratio of each building by using the verified modal identification method, taking the height, the length-width ratio, the first-order natural vibration period, the structural material, the transverse load resistance coefficient and the vibration amplitude parameter of the building as influence factors, respectively performing regression analysis on the damping ratio and the influence factors, and analyzing the influence of different parameters on damping.
Owner:HUBEI EARTHQUAKE ADMINISTRATION (SEISMOLOGY RES INST OF CHINA EARTHQUAKE ADMINISTRATION)

Structural dynamics model correction method

The invention discloses a structural dynamics model correction method, and belongs to the technical field of model correction. S10, establishing a finite element model of the structure, and setting a correction variable and a value range and an initial value thereof; s20, modal finite element analysis and experimental test value comparison are carried out; s30, if the error between the simulation value and the test value exceeds the allowable range, the step S20 is repeated, and the finite element model is updated; s40, updating the finite element model by utilizing a correction result in the step S30; s50, resetting the correction variable, the range of the correction variable and the initial value of the correction variable; s60, harmonic response finite element analysis and experimental test value comparison are carried out; s70, if the error between the simulation value and the test value exceeds the allowable range, adjusting the correction variable, and repeating the step S60 until the error meets the requirement; and S80, updating the finite element model to complete correction. According to the method, data of a plurality of excitation points and a plurality of response points are included at the same time, the problem of model correction result deviation caused by only using a single excitation point or a single response point at a time is effectively avoided, and the reliability and accuracy of a correction result are improved.
Owner:INST OF INTELLIGENT MFG GUANGDONG ACAD OF SCI +1

Industrial axial flow compressor last-stage stationary blade blocking flutter analysis method and equipment and medium

The invention relates to the technical field of industrial axial flow compressors, and discloses an industrial axial flow compressor last-stage stationary blade blocking flutter analysis method and device and a medium. The last-stage stationary blade blocking flutter analysis method comprises the steps that a structural dynamics control equation and a flow control equation are rapidly solved through a fluid-solid decoupling method; aerodynamic damping is obtained based on unsteady CFD analysis of a harmonic balance method, and finally the risk of blocking and fluttering of the last-stage stationary blade is judged according to the numerical value of the aerodynamic damping. The equipment and the medium are used for storing a computer program, and the last-stage stationary blade blocking flutter analysis method is achieved when the computer program is executed. The method has the characteristics of high risk estimation accuracy, simplicity, convenience and feasibility, and can further improve the operation safety and reliability of the industrial axial flow compressor.
Owner:XIAN SHAANGU POWER CO LTD

Analysis and design-based topological optimization method for ocean engineering structure under continuous iteration random excitation

The invention discloses an analysis and design-based topological optimization method for an ocean engineering structure under continuous iterative random excitation, which takes a dynamic response displacement root-mean-square at a specified key position of complex random excitation as a target function, and adopts a virtual excitation method to efficiently solve structural dynamic random response. In order to overcome the problem of huge calculation amount consumption of structural random response dynamics optimization repeated modal solution, a continuous iterative random dynamic response optimization strategy based on analysis and design is provided, and based on an adjoint method, the efficient optimization sensitivity of structural random dynamic response is deduced, and the optimization sensitivity of the structural random dynamic response is improved. An optimization algorithm based on a moving asymptote method is adopted to solve an optimization problem. Optimization examples show that the virtual excitation method based on analysis and design can obtain almost the same optimization design on the basis of having the remarkable calculation efficiency advantage as the traditional double-circulation virtual excitation method.
Owner:DALIAN UNIV OF TECH

Large flexible wing static aeroelasticity analysis method based on physical information neural network

The invention discloses a large flexible wing static aeroelasticity analysis method based on a physical information neural network, and belongs to the field of aircraft design. The method comprises the following steps: for the wing with the super-high aspect ratio, firstly, dispersing the wing into n spanwise sections based on a strip theory, and initializing a reference angle-of-attack parameter of each spanwise section; then, a physical information neural network (PINN) is built, unsteady flow field solving is carried out on each section, for the current ith iteration, the physical information neural network is used for sequentially traversing and extracting pressure distribution of the airfoil surface of each section, respective aerodynamic load distribution is calculated, and the generalized force of the airfoil is obtained; and solving a structural dynamics equation based on the generalized force and structural information of the wing, calculating the deformation of the large-deformation wing by using a modal rotation method, and finally, carrying out solving iterative circulation on aerodynamic force and structural deformation until the attack angle is converged, so as to obtain the actual lift force L of the wing. According to the method, the calculation precision and efficiency are remarkably improved, and different flight conditions and wing design can be adapted.
Owner:BEIHANG UNIV

Monitoring and early warning method for near-road falling type dangerous rock under driving excitation

The invention belongs to the technical field of geological disaster monitoring and early warning, and particularly relates to a near-road falling type dangerous rock monitoring and early warning method under driving excitation. The method utilizes a sensor technology to capture the vibration response of the rock mass when a vehicle passes, calculates the natural vibration frequency early warning threshold value of the dangerous rock mass based on fracture mechanics and structural dynamics, obtains a natural vibration frequency monitoring curve of the dangerous rock mass according to monitoring, and combines the natural vibration frequency early warning threshold value of the dangerous rock mass. And carrying out real-time monitoring and early warning on the stability of the dangerous rock. According to the method, the defects existing in a traditional method are overcome, an effective way is provided for real-time evaluation and early warning of the stability of the dangerous rock, the accuracy and response speed of dangerous rock monitoring can be improved, and safety accidents caused by falling of the dangerous rock are reduced.
Owner:CHONGQING GEOLOGY & MINERAL EXPLORATION & DEV BUREAU NANJIANG HYDROGEOLOGY ENG GEOLOGY TEAM

Parameter tuning method suitable for floating fan multiple tuned mass damper

The invention relates to the technical field of floating fans, in particular to a parameter tuning method suitable for a multi-tuned mass damper of a floating fan, which sequentially comprises the following steps of: establishing a system dynamics model; defining an optimization variable and a constraint range; constructing a comprehensive fitness function; initializing a grey wolf population and algorithm parameters; executing a grey wolf position optimization updating mechanism; setting convergence judgment conditions; and outputting the optimal TMD parameter combination. According to the method, structural dynamic characteristics and an intelligent algorithm strategy are fully fused, particularly, spatial arrangement coordinates of the TMD are brought into an optimization variable domain, collaborative design of tuning parameters and arrangement space is achieved, the method is different from a single-parameter or fixed-point optimization mode, the limitation of artificial experience layout is avoided, overall suppression of structural multi-order modal response is achieved, and the method is suitable for large-scale popularization and application. The damping capacity and the stability margin of the fan structure under wind wave flow coupling excitation are improved, cross-modal and multi-source vibration cooperative treatment is achieved on the system response coordination and control strategy level, and the method has the adaptability to offshore wind power scenes.
Owner:SANYA SCI & EDUCATION INNOVATION PARK WUHAN UNIV OF TECH

Nonlinear system dynamic characteristic calculation method based on structural dynamic modification

The embodiment of the invention discloses a nonlinear system dynamic characteristic calculation method based on a structural dynamic modification method, and the method achieves the high-precision reduced-order modeling of a nonlinear structure through enabling a complex nonlinear effect to be equivalent to an additional stiffness field and combining with a structural dynamic modification algorithm. And based on the decoupled linear substructure modal space, a nonlinear correction operator is introduced, and the global dynamic response of the nonlinear structure is solved through a resolving method after modification. Structural vibration frequency, vibration shape and energy dissipation characteristics under a nonlinear effect can be efficiently obtained, and dynamic characteristics under different nonlinear amplitudes can be obtained. Compared with a traditional iteration method, the method has the advantage that the calculation complexity is remarkably reduced by equivalently linearizing a nonlinear part.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Method and system for analyzing pressure of external liquid storage structure under action of explosive shock wave load

The invention belongs to the technical field of pressure analysis, and discloses a pressure analysis method for an external liquid storage structure under the action of an explosive shock wave load, which comprises the following steps: analyzing the dynamic response process of the external liquid storage structure under the action of the explosive shock wave load according to the dynamic response process of a non-liquid-storage structure, and theoretically calculating and solving the dynamic response process of the external liquid storage structure. The displacement and deformation theoretical solution of the external liquid storage structure is obtained, and the calculation time is greatly shortened. The method comprises the following steps: establishing a structural dynamic response theoretical model of an external liquid storage structure under the action of explosive shock wave load, taking a liquid storage container and a liquid medium as the additional mass mw of the structure, determining a structural dynamic response process according to the thickness of a liquid layer and considering the restrictive action time of the liquid medium on structural deformation, and calculating the structural dynamic response by solving a structural displacement solution. The deformation condition of the external liquid storage structure under the action of the explosive shock wave load is obtained, the solving efficiency is greatly improved, and the defects that finite element simulation solving is low in efficiency and long in consumed time are overcome.
Owner:NAVAL UNIV OF ENG PLA

Dam flood discharge safety protection method and system based on earthquake response analysis

The invention belongs to the field of dam flood discharge safety, and provides a dam flood discharge safety protection method and system based on earthquake response analysis, and the method comprises the steps: S1, obtaining multi-source environment and structure data in real time; s2, preprocessing the multi-source environment and structure data to form a unified time sequence multi-dimensional data set; s3, simulating and analyzing the structural dynamic response of the dam and the flood discharge gate based on the unified time sequence multi-dimensional data set, and evaluating potential damage; s4, comprehensive risk assessment is carried out by combining the earthquake response analysis and damage assessment result, the hydro meteorological data and the flood discharge gate operation state data, and early warning information is generated; s5, generating a dynamically adaptive flood discharge gate opening and closing strategy according to the comprehensive risk assessment result and the early warning information; s6, executing the opening and closing strategy of the flood discharge gate, and monitoring the actual operation state of the flood discharge gate in real time; and carrying out comparative analysis on the actual running state of the flood discharge gate and the prediction strategy, and carrying out updating and optimization according to an analysis result.
Owner:CHINA POWER CONSRTUCTION GRP GUIYANG SURVEY & DESIGN INST CO LTD +2

Vibration and conventional fatigue load coupled nonlinear damage accumulation prediction method

The invention discloses a vibration and conventional fatigue load coupled nonlinear damage accumulation prediction method. The method comprises the following steps: analyzing and determining a peak stress at a dangerous point under the loading of a conventional fatigue load according to a finite element model of an engineering component; determining a stress amplitude probability density function at the dangerous point under random vibration loading according to structural dynamics analysis; searching a pre-generated material fatigue life curve; determining equivalent stress at the dangerous point under random vibration loading according to the fatigue life curve; calculating the ratio of the peak stress loaded by the conventional fatigue load at the dangerous point to the random vibration equivalent stress, and establishing a coupling damage parameter according to the vibration and conventional fatigue load coupling series; and establishing a nonlinear damage accumulation model of vibration and conventional fatigue load coupling. According to the nonlinear damage accumulation model provided by the invention, the influence of vibration, a conventional load sequence and a coupling series is considered, the parameter determination is simple, and high-precision prediction of structural damage evolution under complex load coupling can be realized.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

A method for calculating the vibration response of a layered composite laminate

This invention discloses a method for calculating the vibration response of a delaminated composite laminate, belonging to the field of structural defect calculation and analysis. The method includes: dividing the composite laminate with delamination defects into delaminated and intact regions based on the damage condition; decoupling the delaminated regions dynamically; describing the vibration characteristics of each component in both the delaminated and intact regions using elastic waves based on elastic wave propagation theory, and establishing vibration state vector expressions for each region; determining the compatibility relationship based on the displacement continuity and internal force equilibrium conditions at the coupling point between the delaminated and intact regions, and establishing structural dynamic equilibrium equations in wave space based on the boundary conditions of the composite laminate; solving the structural dynamic equilibrium equations to obtain the amplitudes of elastic waves of each order; and calculating the vibration response of each region of the composite laminate based on elastic wave theory and amplitude calculation. This invention solves the problem of low computational efficiency in existing methods.
Owner:CHINA AIRPLANT STRENGTH RES INST +1

Automatic generation method and device for structural dynamic model of carrier rocket, and storage medium

The invention discloses an automatic generation method and device for a dynamic model of a carrier rocket structure and a storage medium, and belongs to the technical field of carrier rocket model generation, and the method comprises the steps: describing the carrier rocket structure through carrier rocket parameters; reading and storing the edited parameter information of the carrier rocket; and automatically generating a carrier rocket structure dynamic model by using the stored carrier rocket parameters. According to the method, the carrier rocket is subjected to height parameterization description, the method can be combined with a secondary development function of commercial finite element software, rapid and automatic generation and rapid analysis of the model are achieved, and the method has the advantage of being easy to debug.
Owner:ORIENTAL SPACE TECH (SHANDONG) CO LTD

Flow sound mode decomposition method coupling local projection and Helmholtz decomposition

The invention discloses a streaming sound mode decomposition method coupling local projection and Helmholtz decomposition, and relates to the streaming sound mode decomposition field, and the method comprises the steps: employing a local projection method to obtain turbulence coherent structure velocity field time series data and turbulence disordered structure velocity field time series data; respectively carrying out Helmholtz decomposition on the two to obtain a first decomposition result and a second decomposition result; performing divergence on the two decomposition results to obtain a first Poisson equation and a second Poisson equation respectively; carrying out numerical solution on the two Poisson equations to respectively obtain a first scalar potential and a second scalar potential; taking gradients from the two scalar potentials to respectively obtain a turbulent coherent structure acoustic mode velocity field and a turbulent disordered structure acoustic mode velocity field; obtaining a turbulence coherent structure dynamic modal velocity field based on the turbulence coherent structure acoustic modal velocity field; obtaining a turbulence disorder structure dynamic modal velocity field based on the turbulence disorder structure acoustic modal velocity field; according to the method, the flow sound mode decomposition of the nonlinear evolution flow velocity field can be realized.
Owner:CALCULATION AERODYNAMICS INST CHINA AERODYNAMICS RES & DEV CENT

Method for predicting whole-satellite dynamic characteristics of deployable structure during on-orbit deployment

The invention provides a whole-satellite dynamic characteristic prediction method for an expandable structure during in-orbit expansion. The whole-satellite dynamic characteristic prediction method comprises the following steps: establishing a whole-satellite flexible dynamic equation and a flexible multi-body dynamic equation set in an expansion process of the expandable structure; carrying out one-step numerical integration on the flexible multi-body dynamics equation set; according to the integral result, the hinge which is unfolded in place or reaches preset clamping stagnation in the expandable structure is replaced by six-degree-of-freedom force element connection, the clamped hinge and the corresponding connecting part are locked, and a semi-locking and semi-unfolding mixed multi-body dynamic structure dynamic model is established; through modal analysis, rigid body modals are eliminated, and a deployable structure dynamic model is obtained; on the basis of the deployable structure dynamic model and the whole satellite flexible dynamic equation, obtaining a semi-locking dynamic model and a semi-unfolding dynamic model during the on-orbit unfolding period of the satellite; therefore, the problems of whole-satellite attitude stable control input and unfolding fault handling and whole-satellite model handling caused by the fact that the satellite-borne deployable structure is unfolded and locked at the same time during the on-orbit unfolding period can be solved.
Owner:CHINA ACADEMY OF SPACE TECHNOLOGY

Anti-seismic analysis method and system for full-reactor-core assembly of fast reactor and medium

The invention relates to an anti-seismic analysis method and system for a full-reactor-core assembly of a fast reactor and a medium, and the method comprises the steps: carrying out the equivalent decomposition of a full-reactor nonlinear multi-assembly system into a series of linear single-assembly vibration systems; based on numerical simulation, calculating an additional mass coefficient of the feature component to simulate the influence of fluid-solid coupling on component vibration; based on an Euler-Bernoulli theory, a connector and an additional mass coefficient, establishing unrelated finite beam unit models of the single reactor core assembly; carrying out dimensionality reduction on a vibration system of the single reactor core assembly to obtain a solution of a single-degree-of-freedom system; calculating vibration response of the single-degree-of-freedom system under modal coordinates by adopting a central difference method, and converting the vibration response into dynamic response under physical coordinates; if the seismic acceleration time history stops, deflection analysis and contact analysis are performed. According to the method, the structural dynamic response under the gap condition is rapidly solved, and the calculation efficiency of the method is greatly improved.
Owner:INST OF MECHANICS CHINESE ACAD OF SCI

Method and system for predicting inherent frequency of conical plate made of three-phase functionally graded composite material

The invention relates to the technical field of composite material structure dynamics analysis, and provides a method and system for predicting the inherent frequency of a three-phase functionally graded composite material conical plate, and the method comprises the steps: employing an improved Halpin-Tsai model to calculate the equivalent parameters of a GPL-containing two-phase composite matrix, solving the equivalent parameters of a three-phase composite layer, and calculating the inherent frequency of the three-phase composite material conical plate. The method comprises the following steps: constructing a nonlinear geometrical relationship between a displacement field and a strain field, calculating a stiffness coefficient of each layer, constructing kinetic energy of the three-phase composite material conical plate, calculating an energy coefficient according to the stiffness coefficient of each layer, constructing potential energy of the conical plate according to the energy coefficient, and constructing a modal displacement function by adopting a Chebyshev polynomial and a boundary function. And establishing a characteristic equation based on a minimum potential energy principle and solving to obtain the inherent frequency of the three-phase composite material conical plate. According to the method, efficient calculation of the inherent frequency of the three-phase composite material conical plate is achieved, and the reliability and engineering application value of structural dynamics analysis are remarkably improved.
Owner:TIANJIN POLYTECHNIC UNIV

High-speed aircraft thermal protection plate thermodynamic elasticity rapid calculation method based on aerodynamic force / thermal agent model

The invention discloses an aerodynamic force / thermal agent model-based rapid calculation method for the thermo-dynamic elasticity of a thermal protection plate of a high-speed aircraft, and the method comprises the steps: building an unsteady aerodynamic force / thermal agent model of a thermal protection wall plate in a high-speed flow based on a Kriging agent model method; a structural dynamics method based on a finite element method is used for establishing an aeroelastic module, a transient heat conduction equation is used for establishing an aerothermal module, and a thermal protection wallboard thermodynamic elasticity analysis frame is built. Finally, the aerodynamic force / thermal agent model is used for carrying out thermal protection wall plate thermodynamic elasticity calculation and analysis. Compared with a traditional high-order method, the calculation efficiency is improved by four orders of magnitude.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Dynamic calculation method based on spectral feature coding network

The invention discloses a dynamic calculation method based on a spectral feature coding network. The dynamic calculation method comprises the following steps: analyzing a structural dynamic equation type and modal parameters corresponding to a dynamic problem to be solved; determining an input variable of the structural dynamic equation, building a spectrum feature coding layer, and mapping the input variable to a spectrum space related to the structural dynamic equation solution; constructing a neural network architecture; constructing a loss function based on physical constraint conditions of the structural dynamic equation; and training the neural network architecture under the constraint of the loss function, and solving the structural dynamic equation to respond to dynamic calculation. The input variable is projected to the structural dynamic equation frequency spectrum space, and the multi-layer perceptron fits the primary function with the clear physical meaning in the space, so that the frequency spectrum deviation problem is effectively solved, the solving precision of the high-frequency structural dynamic equation is improved, the nonlinear fitting complexity of the neural network is reduced, and the neural network performance is improved. The method enables the network to converge rapidly, reduces the number of iterations to improve the solving efficiency, and provides a high-efficiency solving thought for an engineering high-frequency dynamics problem.
Owner:HUNAN UNIV

Wind tunnel test aerodynamic force and displacement signal phase difference correction method and system based on self-excited vibration characteristics and storage medium

The invention discloses a wind tunnel test aerodynamic force and displacement signal phase difference correction method based on self-excited vibration characteristics. The method comprises the following steps: independently collecting structure surface wind pressure and vibration displacement signals; integrating the wind pressure signal to obtain a self-excitation aerodynamic force time history; identifying the vibration frequency and the total damping ratio of the system from the displacement signal; filtering the aerodynamic force time history to extract a fundamental frequency component; based on a structural dynamic balance principle, establishing an analytic relational expression between an aerodynamic force out-of-phase component coefficient and total damping of the system; and carrying out iterative time translation on the aerodynamic force time history by taking the displacement signal as a reference until the out-of-phase component of the aerodynamic force time history meets the analytic relationship, so as to determine and correct the system delay. The invention further discloses a wind tunnel test aerodynamic force and displacement signal phase difference correction system based on the self-excited vibration characteristic and a storage medium. According to the method, electric triggering and physical transmission delay can be compensated with high precision without additional hardware, and the pneumatic parameter identification reliability is effectively improved.
Owner:CHONGQING UNIV

System-level coupling modeling method, system, equipment and medium for multi-wind-wheel multi-tower-drum floating type wind turbine generator

The invention discloses a system-level coupling modeling method, system, equipment and medium for a multi-wind-wheel multi-tower-drum floating type wind turbine generator set, and relates to the field of simulation modeling, and the method comprises the steps that parameter information of the multi-wind-wheel multi-tower-drum floating type wind turbine generator set is obtained, and a multi-system structural dynamics model is obtained based on the parameter information of the multi-wind-wheel multi-tower-drum floating type wind turbine generator set; the unsteady aerodynamic model, the hydrodynamic model and the mooring structure dynamic model are used for outputting aerodynamic loads, hydrodynamic loads and mooring cable tension, the aerodynamic loads, the hydrodynamic loads and the mooring cable tension are fed back to the multi-system structure dynamic model, and based on a Lagrange framework, the models are subjected to joint simulation operation through a joint simulation interface, so that the mooring cable tension is obtained. And the multi-wind-wheel and multi-tower-drum floating type wind turbine generator is designed. According to the method, a complete system dynamics model can be established, and complete machine level rapid evaluation and engineering iteration under multiple working conditions can be supported.
Owner:NORTH CHINA ELECTRIC POWER UNIV