45 results about "Harmonic excitation" patented technology

The invention provides a dry-type transformer turn-to-turn short circuit multi-physical field simulation analysis method considering insulation aging and harmonic influence, and relates to the technical field of simulation analysis, and the method comprises the following steps: constructing a physical simulation model of a to-be-tested dry-type transformer; setting physical parameters and multi-physical field operation conditions of the physical simulation model; calculating a corresponding physical field operation calculation result under each physical field operation condition; performing post-processing on the physical field operation calculation result; by establishing a detailed simulation model and accurately assigning physical property parameters of each component, physical property changes of the turn-to-turn insulating material at different aging stages and under different temperature and frequency conditions are emphatically considered; turn-to-turn short circuit fault modeling is further introduced, magnetic-thermal-flow coupling simulation calculation is carried out under multi-harmonic excitation, the multi-physical field distribution characteristics of the dry-type transformer during different turn-to-turn short circuit faults are explored, and a reliable basis is provided for design optimization and safety evaluation.

The invention relates to the technical field of light storage and charging integration, in particular to an intelligent micro-grid power supply and load balance control method based on light storage and charging integration, which comprises the following steps of: synchronously acquiring a photovoltaic string output current frequency spectrum, a charging pile switching frequency set and an energy storage converter impedance curve, and outputting a mismatch characteristic frequency spectrum; the mismatch characteristic frequency spectrum marks a resonance risk frequency band; and based on the mismatched characteristic frequency spectrum, generating a light-storage-charging power coordination instruction set through a harmonic suppression collaborator, including instructing a photovoltaic string to start an active damping mode in a resonant frequency band and dynamically distributing differential switching frequency of a charging pile. According to the method, a mismatch characteristic frequency spectrum model fusing a photovoltaic current frequency spectrum, a charging pile switching frequency set and an energy storage converter impedance characteristic is constructed for the first time, a resonance risk frequency band is analyzed and judged through frequency domain coupling, and feedforward identification of inter-harmonic excitation conditions of multi-source high-frequency conversion equipment is realized; the method has higher system level adaptability and harmonic risk positioning precision.

The invention belongs to the technical field of converter transformers, and particularly discloses a converter transformer vibration noise control method and system, a terminal and a medium, and the method comprises the steps: constructing a converter transformer structure geometric model, setting material attributes, and carrying out the grid division; based on the geometric model, establishing an electromagnetic field simulation model, applying excitation conditions, obtaining electromagnetic field distribution, establishing an iron core magnetostriction mathematical model, calculating vibration acceleration caused by magnetostriction and transient electromagnetic force of an iron core and a winding, and solving and extracting a displacement field and stress-strain response; establishing an acoustic coupling model on the basis of a structure vibration result, and calculating sound pressure level distribution under different frequencies by setting a structure-air coupling boundary and a matching layer; according to an acoustic simulation result, an iron core positioning structure and an oil tank reinforcing rib arrangement mode are optimized, vibration noise prediction and control of the converter transformer in a multi-harmonic excitation environment are realized, and equipment structure stability, operation reliability and environment adaptability are improved.

The invention belongs to the technical field of part processing, and provides a multi-harmonic excitation conformal polishing and grinding device and method for ring parts, the device adopts a double-mass double-excitation four-machine reverse split driving mechanical vibration system, high-frequency large-amplitude compound vibration of a conformal container is realized, and the polishing and grinding efficiency is improved. Therefore, the particle medium is driven to perform efficient longitudinal spiral motion around the ring part; the rotary motion of the ring part cooperates with the geometric constraint of the conformal container, so that the relative motion between the particle medium and the ring part is improved, an alternating stress flow field is formed in the ring part, and the problem that the inner surface machining efficiency and the outer surface machining efficiency are inconsistent due to the splitting effect of the ring part on the particle flow field is successfully solved. By means of the method, the problems of low machining efficiency, uneven machining and poor surface quality existing in a traditional finishing machining method for the ring parts with the cartridge receiver and the flame tube as typical parts can be solved, and the machining cost is reduced while the machining precision and the surface quality of the ring parts are improved.

The invention belongs to the technical field of medical imaging, and provides a tissue stress measurement method and system based on a reverberation shear wave field, and the method comprises the steps: applying steady-state harmonic excitation, and obtaining the reverberation shear wave field of a target tissue; determining a stress direction according to the prior information of the target tissue, and constructing a stress direction vector; constructing an analytic operator, and extracting an intermediate characteristic quantity of the reverberation shear wave field; and according to the intermediate characteristic quantity, combining stress direction inversion to reconstruct spatial stress distribution. According to the method, a complex reverberation wave field is modeled into superposition of multi-direction propagation wavelets by utilizing anisotropic propagation characteristics of shear waves and combining a traveling wave expansion model, and characteristic quantities related to local stress and material parameters are directly extracted from the reverberation wave field by designing a wave field operator with physical significance; the three technical problems existing in a traditional shear wave elastic imaging technology are solved, the dependence of a traditional method on a single propagation direction and wave pattern controllability is broken through, and in-situ, in-vivo and non-invasive quantification is achieved.

The invention discloses a high-frequency vibration absorption fastener design method for restraining local bending mode vibration of a steel rail. The method comprises the following steps that a finite element analysis model of the steel rail is established according to the set length and steel rail parameters, a rail model under the harmonic excitation condition is established, and a relational expression met by the overall rigidity and damping of a double-layer fastener model is established; constructing a kinetic equation of vertical movement of the iron base plate; constructing a target optimization function for designing the track fastener system based on the error; and constructing a cost model of the fastener in the production process, optimizing cost control of fastener design, outputting the quality of the iron base plate, the rigidity of the upper layer structure and the rigidity of the lower layer structure under the optimal cost control, and designing the fastener system. According to the method, high-feasibility solutions are provided for relieving local bending modal vibration of the steel rail, high-order polygons of wheels and corrugation of the steel rail.

The application discloses a kind of vibration characteristics analysis methods of water turbine guide vane shaft-top cover rubbing coupling system, comprising the following steps: S1, using finite element method in combination with fixed interface modal synthesis method, the reduced dynamic model of guide vane shaft-top cover rubbing coupling system is established;S2, based on reduced dynamic model analysis mode truncation number, the influence law of friction coefficient and water flow surface load on the prestressed modal characteristics of guide vane shaft-top cover rubbing coupling system first 3 orders;S3, when reduced dynamic model is subjected to simple harmonic excitation, the influence law of near load end contact state, near-far load end contact state and friction coefficient on the vibration response and frequency spectrum characteristics of guide vane shaft-top cover rubbing coupling system;S4, based on the above steps, whether mixed-flow water turbine is stably and safely operated is evaluated.The application is analyzed by vibration characteristics of mixed-flow water turbine guide vane shaft-top cover rubbing coupling system, to monitor and diagnose the structural health state and failure of mixed-flow water turbine.

This invention relates to the field of nonlinear node detection technology, and particularly to a nonlinear electronic node concealment detection system based on S-band harmonic fingerprinting. The system includes: acquiring fundamental and second harmonic echo signals from multiple detection nodes within the detection area in the S-band to ensure a sufficient data source for the entire detection process; constructing harmonic excitation response features and generating a fingerprint database to improve the accuracy and targeting of subsequent node identification; dynamically capturing the node's current characteristic information by transmitting S-band frequency sweep detection signals and collecting echo harmonic components to extract real-time fingerprints, enhancing the timeliness of node detection; identifying matching concealed electronic nodes by performing multi-dimensional time-series correlation matching between real-time harmonic fingerprints and fingerprints in the fingerprint database, effectively filtering out irrelevant interference; and generating a topology map and marking abnormal nodes, enabling users to quickly grasp the overall situation and rapidly locate anomalies.

The invention relates to a wheel polygon wear suppression method, an inter-harmonic excitation suppression circuit, a method and a medium, and relates to the technical field of railway traction transmission. On the basis of inter-harmonic excitation suppression and polygon wear feedback suppression, the malignant feedback effect caused by electromechanical coupling is weakened, and therefore suppression of polygon wear development of the wheel is achieved; the inter-harmonic excitation suppression comprises the following steps of: arranging an active power filter in a direct current link, and compensating direct current link power fluctuation caused by harmonic waves introduced by a rectifier; the polygon abrasion feedback suppression comprises the steps that compensation current is calculated based on the rotating speed fluctuation quantity under polygon abrasion excitation, and the T-axis current of the motor is compensated. According to the scheme, corresponding technical measures can be put forward from the two aspects of inter-harmonic excitation source suppression and polygon wear feedback suppression, comprehensive suppression of development of polygon wear of the wheel is achieved, polygon wear of the wheel caused by electrical parameters is reduced, and the method has the advantages of being low in implementation cost and not prone to being affected by the external environment.

The invention relates to the technical field of hydraulic bushings, in particular to a hydraulic bushing modeling and fatigue life acceleration prediction method for a new energy automobile suspension, which comprises the following steps: S1, collecting data and analyzing the driving condition characteristics of a new energy automobile; s2, the structure of the hydraulic bushing is selected, and parameters of the hydraulic bushing are preliminarily determined; s3, checking the strength and stability of the hydraulic bushing; s4, analyzing the sensitivity of each parameter and determining an optimizable parameter, wherein the sensitivity analysis comprises local sensitivity analysis and global sensitivity analysis; s5, based on a simple harmonic excitation experiment, fitting model initial parameters by using a classic frequency domain identification method; and S6, fitting the parameters of the mixed lumped parameter model of the hydraulic bushing according to the experimental data. According to the technical scheme, through the innovative modeling method and the fatigue life prediction method, the dynamic performance prediction precision and the fatigue life evaluation accuracy of the hydraulic bushing for the new energy automobile suspension are remarkably improved.

The application provides an offshore wind turbine structure modal parameter automatic identification method, comprising: power spectrum density analysis on measured structural dynamic response of an offshore wind turbine structure, identification of harmonic frequencies by using a long short-term memory (LSTM) deep learning network; obtaining the dynamic response of the offshore wind turbine structure only with environmental excitation by using a periodic sub-signal-Kalman filter; then obtaining a Monte Carlo stability diagram by using a Monte Carlo covariance-driven stochastic subspace identification method, and further identifying stable modes of the structure; finally, obtaining modal parameters of the offshore wind turbine structure by using a density-based noise application spatial clustering method. The application can effectively solve the challenge of harmonic excitation to modal parameter identification, improve the accuracy of structural modal parameters, and improve the structural health monitoring, state evaluation and damage identification capability of the offshore wind turbine, thereby supporting the development of offshore wind energy.

This invention discloses an electromagnetic coil winding detection system and method, belonging to the field of electromagnetic coil winding technology. It solves the problem in segmented electromagnetic coil windings of high-voltage high-frequency transformers where distributed parameter resonance and high-frequency harmonic coupling generate dynamic interlayer overvoltages, continuously inducing partial discharges, ultimately leading to winding breakdown and short circuits, and the cause of failure is difficult to trace. The system includes a data acquisition module, a data preprocessing module, a resonance feature extraction module, a parameter calculation module, a risk index calculation module, a product-level judgment module, and a batch statistical process control module. This invention collects impedance data of the electromagnetic coil at multiple frequency points and preprocesses it to extract resonance feature parameters. It then calculates the resonance amplification factor and harmonic excitation intensity by combining operating parameters, and further integrates the quality factor and frequency matching degree to generate a comprehensive risk index. Based on this index, the coil is graded, and batch data is statistically controlled to issue process warnings.

The invention discloses a dual-unit motor modal parameter identification method based on sideband harmonic excitation, and belongs to the field of motors. The method comprises the following steps: selecting sideband harmonic current with a preset frequency as a vibration excitation source; selecting the rotating speed when the sideband harmonic current is maximum as a test rotating speed; performing switching frequency sweeping on the to-be-tested dual-unit motor to obtain vibration acceleration data of each test point; carrying out carrier phase shift processing on the sideband harmonic waves by adopting different phase shift angles, and repeating the test steps to respectively obtain vibration acceleration data of each test point at different orders; selecting a plurality of suspicious resonance points from the vibration acceleration data; vibration mode analysis is carried out according to the corresponding vibration acceleration data, and the space vibration mode, the vibration order and the inherent frequency of a real resonance point are determined; and constructing a frequency response function according to the real resonance points, and extracting modal parameters of the to-be-tested dual-unit motor from the frequency response function. And modal parameter identification with low cost, high excitation energy and wide frequency range is realized.

The multi-harmonic excitation polisher machine comprises a charging barrel, a bottom vibration exciter, a left vibration exciter and a right vibration exciter, the bottom vibration exciter is arranged at the bottom of the charging barrel and used for driving the charging barrel to vibrate up and down in a reciprocating mode, and the left vibration exciter and the right vibration exciter are arranged on the two sides of the charging barrel respectively and used for driving the charging barrel to vibrate obliquely in a reciprocating mode; under the cooperation of the bottom vibration exciter, the left vibration exciter and the right vibration exciter, the charging barrel can generate multi-direction collaborative vibration, and grinding materials in the charging barrel can do conventional horizontal or vertical movement and also present a more complex spiral rising movement mode; by means of the movement mode, the contact frequency, the contact angle, the contact area and the contact time between the grinding material and the workpiece are increased, and the polishing and grinding effects on the workpiece can be improved; and meanwhile, the spiral ascending movement is also beneficial to uniform distribution of the grinding materials on the surface of the workpiece, so that the condition of local excessive wear or non-in-place treatment is avoided.

The invention provides a non-linear Lamb wave frequency dispersion effect-based fingerprint iterative imaging method. The method comprises the following steps of: acquiring a time domain sound field signal and a fingerprint grayscale image when a fingertip presses a glass plate; frequency dispersion curve changes of Lamb wave fundamental waves and second harmonics are calculated, and second harmonic excitation parameters are determined; constructing a fingerprint ridge-valley image, and establishing a speed model; determining a second harmonic propagation velocity by using a group velocity frequency dispersion curve, extracting signal features, and establishing a frequency domain sound field matrix; fingerprint primary positioning is completed through secondary harmonic ray tomography, and an initial model and a sound field matrix are updated; establishing an offline training data set, and training by adopting a supervised descent method; and completing fingerprint iterative imaging by using the descending gradient matrix output by training. According to the method, the high sensitivity of the nonlinear Lamb waves to fingerprints is utilized, the method has the characteristics of zero occupation of space under a transducer screen, small data set and low imaging error, and wide-area, accurate and rapid representation of submillimeter fingerprint details can be realized.

The invention relates to the field of ship structure safety evaluation, and discloses a large-area distributed random ice load frequency domain identification mathematical model morbidity elimination method, which comprises the following steps: firstly, by establishing a finite element model comprising a ship hull plate, a rib and a stringer structure, converting an ice load effect into an equivalent concentrated force model; the method comprises the following steps: firstly, constructing a structure, arranging multiple strain response measuring points on the surface of the structure, then obtaining frequency response data by applying simple harmonic excitation, forming a frequency response function matrix, optimizing a high morbid frequency through a multiple expansion retrieval algorithm, screening out a submatrix with the minimum condition number, reconstructing a frequency domain identification model, and finally, identifying the high morbid frequency according to the frequency domain identification model. And based on the optimized frequency response function sub-matrix, combining a structure response spectrum and an inverse problem theory, and solving by utilizing a generalized inverse method to obtain an ice load power spectral density function. A frequency response function matrix is optimized through a multiple expansion retrieval algorithm and a generalized inverse method, the stability and recognition precision of the model are remarkably improved, and the problem of discomfort caused by high ill-conditioned frequency in an existing method is solved.

This invention provides a transformer loss detection method based on CNN-BiLSTM and SFG, belonging to the field of transformer technology. This invention establishes a finite element simulation model of a converter transformer, including harmonic excitation and DC bias conditions, using the SFG adaptive sparse mesh partitioning algorithm. It generates a training dataset of three-phase voltage and current waveforms and magnetic field loss temperature distribution. A physical constraint model is constructed, integrating a CNN feature extraction layer, a BiLSTM time-dependent layer, and Joule's law constraint terms embedded in Maxwell's equations for heat conduction. The model outputs predicted loss results using real-time acquired measured three-phase voltage and current waveforms as input, and sends adjustment commands to the monitoring system or cooling control system based on the loss difference. This solves the technical problem of difficulty in real-time and accurate detection of the loss state during converter transformer operation.

The present invention provides a method for identifying structural fatigue cracks based on the collaboration of VMD-HHT, comprising the following steps: applying a harmonic excitation at the end position of the structure to be identified, collecting the acceleration response data at different positions of the structure, and using wavelet packet transform to perform decomposition, noise suppression and reconstruction processing in sequence to obtain a reconstructed acceleration signal with noise reduction; performing variational mode decomposition on the reconstructed acceleration signal to obtain intrinsic mode functions; performing Hilbert-Huang transform on each intrinsic mode function respectively to obtain a Hilbert spectrum set; when multi-order secondary high-frequency signals appear in the Hilbert spectrum set, a fatigue crack occurs at the response data acquisition position of the structure, and the greater the instantaneous frequency amplitude of the multi-order secondary high-frequency signals, the greater the fatigue crack. This method combines the advantages of VMD and HHT, overcomes the problem of false intrinsic mode function information, improves the ability to decouple different frequency components in narrow-band signals, and can effectively distinguish frequency differences.

The invention provides an automatic identification method for modal parameters of an offshore wind turbine structure, and the method comprises the steps: carrying out the power spectrum density analysis of the actual measurement structure dynamic response of the offshore wind turbine structure, and recognizing the harmonic frequency through a long short-term memory (LSTM) network deep learning network; obtaining the dynamic response of the offshore wind turbine structure only excited by the environment by using a periodic sub-signal-Kalman filter; using a Monte Carlo covariance driven random subspace identification method to obtain a Monte Carlo stability graph, and further identifying the stability mode of the structure; and finally, obtaining modal parameters of the offshore wind turbine structure by using a density-based noisy application space clustering method. According to the invention, the challenge of harmonic excitation to modal parameter identification can be effectively solved, and the accuracy of the structural modal parameters is improved; and meanwhile, the structural health monitoring, state evaluation and damage identification capabilities of the offshore wind turbine are improved, so that the development of offshore wind energy is supported.

The invention provides a surface acoustic wave device structure and device, the surface acoustic wave device structure comprises a substrate and a piezoelectric layer formed on the substrate, the piezoelectric layer comprises a first region and a second region which have different polarization directions and are periodically alternated, and an IDT electrode is formed on the piezoelectric layer. Comprising first electrode fingers and second electrode fingers which are sequentially staggered at intervals, extend and vertically penetrate through the first area and the second area. The specific proportional relation between the polarization direction difference of the first area and the second area of the piezoelectric layer and the periodic structure size and the wavelength of the surface acoustic wave determined by the IDT electrode is utilized, higher harmonic excitation and fundamental wave suppression are achieved, the working frequency range of the surface acoustic wave device is effectively expanded, the high-frequency communication requirements of 5G / 6G and the like can be met, and the application prospect is wide. And a basis is provided for application of the surface acoustic wave device in multiple fields.

This disclosure provides a method for manufacturing a rubber roller in a printing system and a printing system thereof. The method for manufacturing the rubber roller in the printing system includes: establishing a finite element analysis model of the rubber roller; determining the natural frequencies and mode shapes of the rubber roller based on the finite element analysis model; performing frequency response analysis based on the natural frequencies to obtain frequency response results under harmonic excitation; using the frequency response results to at least determine weak regions of the rubber roller that do not meet performance conditions; constructing dynamic equations based on the frequency response results and mode shapes, and obtaining the dynamic characteristics of the rubber roller based on the dynamic equations; constructing a topology optimization model and constraints based on the dynamic characteristics; optimizing the parameters of the rubber roller through iterative calculation of the topology optimization model based on the constraints to obtain optimized parameters; and manufacturing the rubber roller according to the optimized parameters.

The invention relates to the technical field of intelligent optimization of structural parameters of dampers of wind power generation equipment, and discloses an intelligent optimization design method for parameters of an offshore wind power damper. A damping coefficient, a rigidity coefficient and a piston stroke form a parameter vector, an upper bound and a lower bound are set, an input amplitude, frequency and an initial phase are recorded according to a harmonic sequence number, and multi-harmonic excitation is established. Enabling the device to be equivalent to a single degree of freedom, calculating the steady-state amplitude and phase difference of each order, and forming frequency-amplitude mapping; setting a unified target amplitude and being constrained by a stroke, and constructing frequency domain measurement based on full-order deviation square; calculating damping and rigidity gradients of the measurement to form vectors, performing updating, boundary and stroke projection, closed correction and resonance rejection in combination with the minimum step pitch and the threshold value, and defining minimum distinguishable change and convergence by tolerance; recalculating the step length and projection for the overrun order, and lowering the target when necessary; and finally, through step-by-step energy balance checking, outputting optimal damping, rigidity and stroke recorded values and a full-order response table.

The invention belongs to the technical field of dynamic modeling and vibration control of a single-screw pump set, and discloses a simplified single-screw pump set dynamic model based on a vibration isolator and an application method of the simplified single-screw pump set dynamic model. According to the model, main components such as a pump, a speed reducer, a motor and a bottom plate in the single-screw pump set are simplified into equivalent mass blocks; the two rows of vibration isolators are combined into one group, and a pump set kinetic model is established according to the single-degree-of-freedom mass-spring-damping system characteristics of the vibration isolators. And deducing a frequency response function of the system by using a Newton's second law and a rigid body rotation law. According to the method, the calculation complexity of the dynamic model is greatly reduced, the vibration response of the pump set under harmonic excitation can be accurately predicted, and a theoretical basis is provided for structural optimization, fault diagnosis and vibration control of the pump set. The model is suitable for vibration analysis of the single-screw pump set under high-load and complex working conditions, and has wide engineering application prospects.

The invention discloses a vehicle active suspension control parameter optimization method under random excitation, and relates to the technical field of vehicle active suspension control, and the method comprises the following steps: firstly, constructing a quarter vehicle active suspension system considering time delay control according to the structure of a vehicle active suspension system; secondly, converting multi-frequency pavement excitation in a continuous time interval into simple harmonic excitation with an equivalent effect in a discrete time interval through a simple harmonic equivalent method, and calculating the frequency and amplitude of simple harmonic excitation force in the discrete time to serve as deterministic load input; and then, calculating the response of the structure by adopting a structure dynamic analysis method. And finally, selecting a typical pavement excitation form, and verifying the complex excitation simple harmonic equivalent excitation method. On the basis of the simple harmonic equivalent excitation method, the riding comfort and the driving stability of the automobile can be effectively improved while the analysis precision is guaranteed.

A kind of harmonic modal detection and removal method based on blind source separation, rotating machinery generates harmonic excitation to structure in running state, based on the vibration response acceleration signal obtained by measurement, harmonic modal will appear in modal parameter identification, cause modal parameter identification error, low identification accuracy and other problems, harmonic modal should be detected and removed.In this method, based on the high similarity between modal expansion and blind separation principle, the vibration signal is analyzed under the condition of underdetermination sparse component, the energy peak scatter is clustered to estimate the mixing matrix by using the maximum energy method, and then the source signal is recovered based on the principle of minimum L1 norm;The probability density curve of each source signal is calculated, and the position of the harmonic modal is preliminarily determined;For the source signal containing harmonic, a spectral kurtosis curve diagram is drawn, so as to detect the frequency value corresponding to the harmonic modal;The corresponding harmonic source is removed, and the signal without harmonic interference is reconstructed.

The invention provides a zero-order horizontal shear wave regulation and control method and device and application thereof, and relates to the technical field of metamaterials, and the method comprises the steps: carrying out the unit cell division of a single meta-structure element and a plate structure based on an anti-resonance principle, and carrying out the equivalent mass construction of divided unit cells, and forming a spring mass system; simple harmonic excitation force is applied to the spring mass system based on the Newton's law of motion, a mass motion control equation is established, the mass motion control equation is solved through an anti-resonance mechanism, and an anti-resonance geometric configuration is obtained; deducing the anti-resonance geometric configuration in combination with a cylinder approximation method and preset anti-resonance boundary conditions according to shear deformation characteristics of zero-order horizontal shear waves to obtain a superstructure primitive geometric parameter scheme; and regulating and controlling the propagation of the zero-order horizontal shear wave through the metasurface elements in different arrangement modes based on the metasurface elements with the optimal size in the metasurface element geometric parameter scheme. According to the method, the problem that the zero-order horizontal shear wave cannot be accurately and losslessly effectively controlled is solved.

The invention discloses a towed linear array vibration isolation module bidirectional fluid-solid coupling simulation method. The method comprises the following steps: constructing a finite element structure model of a vibration isolation module; calculating a viscous damping coefficient for an equivalent fluid damping effect; inserting and configuring a spring element with the damping coefficient between adjacent components in the model; performing grid division on the model; applying pretension force for statics analysis; applying simple harmonic excitation based on a static analysis result to perform harmonic response analysis; and extracting vibration responses of the input end and the output end, and calculating a vibration isolation quantity frequency spectrum. Complex fluid domain modeling and calculation in traditional bidirectional fluid-solid coupling are equivalently simplified into setting of a parameterized damping spring in a pure structure model, so that the simulation calculation time is greatly shortened from the hour level to the minute level on the premise that the calculation precision is kept (the average error is about 2.74 dB compared with that of a classical method), and the simulation calculation efficiency is greatly improved. The calculation efficiency is obviously improved; and the resource consumption is reduced.

The invention provides a marginal plate damping device optimization method based on Monte Carlo simulation and Latin hypercube design, and the method comprises the steps: selecting a certain order of vibration mode of a blade mode to carry out the structure optimization design of a damper based on the vibration mode of the blade mode, and determining the harmonic response frequency range of the blade; processing a blade group substructure by a dual-mode synthesis method, and combining an overall structure matrix through a substructure reduction matrix; obtaining a parameter matrix and a two-dimensional contact surface friction model, and constructing a dynamic equation set with dry friction nonlinearity; a dynamic equation set with dry friction nonlinearity is obtained, and an amplitude-frequency characteristic curve is solved through a harmonic balance method and an arc length continuation method; monte Carlo simulation and Latin hypercube design are carried out, a multi-parameter Monte Carlo simulation analysis program is written, and parameter optimization analysis with the optimal damping effect of the damping device as the target is completed; and obtaining an optimal parameter group to further optimize the original damping structure. The model is processed through a substructure method, and the vibration response of the blade group with dry friction damping under simple harmonic excitation can be predicted.

The invention belongs to the technical field of converter transformers, relates to an assembly design method for vibration and noise suppression of a converter transformer under harmonic excitation, and designs three iron core structures, four winding structures, two oil tank structures, two foot pad insulation structures and four up-down positioning structures based on three sets of converter transformer scaling model machines with replaceable assemblies. A contrast experiment of the structure is carried out under no-load / load and three-time, five-time and seven-time different harmonic excitation combinations, and the contribution degree of each component structure to the noise reduction level of the converter transformer is given; according to the contribution degree of each component structure to the noise reduction level of the converter transformer, the optimal vibration and noise suppression component combination of the converter transformer is a 9mm six-stepping 135 laminated core, an inner screen entangled winding, a cross-shaped reinforcing rib oil tank, a foot-pad-free insulation and upper eccentric circle positioning-lower pouring positioning structure. The invention provides the optimal topology of the component structure aiming at the vibration characteristic of the converter transformer, and the comprehensive effective noise reduction can reach 15dB.

This invention discloses a vibrating screening device for adjustable coal slurry particle size distribution, relating to the field of coal slurry screening technology. It includes: a segmented screen box, the interior of which is divided into at least two vibration zones along the coal slurry flow direction; a screening component disposed within each vibration zone, the screening component being adjustable in terms of particle size; an excitation system disposed on the segmented screen box, the excitation system being used to apply independently adjustable harmonic excitation to each vibration zone; a feed hopper disposed above the feed end of the segmented screen box; and a microbubble generating component disposed inside the feed hopper, injecting microbubbles into the coal slurry. This invention possesses significant advantages such as multi-zone heterogeneous vibration, stepless orifice adjustment for coal slurry particle size, and microbubble anti-clogging and screen cleaning, significantly improving the separation efficiency of coarse and fine particles and meeting the need for refined adjustment of coal slurry particle size distribution under different working conditions.