16 results about "Hybrid mesh" patented technology

The invention discloses a well periphery flow capacity calculation method based on a hybrid grid. The well periphery flow capacity calculation method comprises the following steps that S1, the hybrid grid is established according to well periphery heterogeneous characteristics; s2, at the beginning of the time step, preliminarily determining fluid pressure in a shaft, and for a large-scale grid, calculating fluid pressure distribution in a matrix rock mass by adopting a seepage numerical model; s3, preliminarily determining the concentration of acid liquor in a shaft, adopting the pressure and the concentration in the shaft as inlet boundary conditions, adopting the recorded large-scale grid boundary fluid pressure as outlet boundary conditions, calculating the growth process of acid etching wormholes in the small-scale grid system by utilizing a wormhole model, and obtaining the change of a porosity field in the small-scale grid system; s4, calculating physical property parameters of the large-scale grid after earthworm hole growth in a single time step; and S5, repeating the steps S2-S4, and carrying out next time step calculation until analog calculation of the whole injection process is completed. According to the invention, the optimal balance between the calculation efficiency and the simulation precision is realized.

The invention discloses a ship fluid computational domain full-automatic non-structural hybrid grid generation method, which comprises the following steps: acquiring a ship geometric model, adding a computational domain bounding box, and generating an initial discrete geometric model consisting of triangular surface grids; acquiring user input control parameters, and generating a size field in combination with the initial discrete geometric model; embedding a symmetric plane and a horizontal plane according to the initial discrete geometric model, generating an initial triangular surface grid with consistent boundaries, and performing re-gridding under the control of a size field to generate a model boundary surface grid; according to a horizontal plane, dividing the boundary surface grid into an upper surface grid and a lower surface grid, and respectively generating an upper boundary layer grid and a lower boundary layer grid which are composed of anisotropic triangular prism units and pyramid units; on this basis, surface grids of the boundary of the computational domain are regenerated at the boundary of the bounding box, tetrahedral grid units are generated under the control of the size field, and therefore the ship fluid computational domain full-automatic non-structural hybrid grid is formed through merging.

This invention relates to the field of submersible electric pump (FET) fault diagnosis technology, and particularly to a method and system for FET fault diagnosis based on CFD and deep learning. The method includes constructing a full-channel 3D model, simulating FET faults by modifying key geometric feature parameters, and using a hybrid mesh strategy to divide the mesh; extracting time-domain and frequency-domain features from the simulation data, forming feature vectors from these features, and constructing multi-dimensional labeled simulation data using these feature vectors and multi-dimensional label vectors; constructing a multi-channel deep neural network, training the multi-channel deep neural network using the multi-dimensional labeled simulation data; and deploying the trained multi-channel deep neural network to a well site edge computing gateway to diagnose FET sensor data. This invention utilizes CFD to generate high-quality data to drive deep learning model training, achieving rapid and accurate collaborative diagnosis of multiple faults in FETs.

This invention provides a multi-grid fusion method for numerical simulation of wind turbine wakes in complex terrain. It fuses Cartesian grids of complex terrain, structured or unstructured hybrid grids of the wind turbine region, and anisotropic O-type structured grids of the wake region. By fusing multiple grid types with different topologies and using overlapping grid technology for assembly and interpolation calculations, this method significantly improves wake vortex analysis efficiency and controls computational costs while ensuring the accuracy of wind turbine aerodynamic loads and automated terrain geometry modeling. This enhances the accuracy and efficiency of numerical simulation of wind field wakes.

The invention discloses a hot hybrid simulation method for a T-shaped pipe of a pressurized water reactor core safety injection system, and the method comprises the steps: building a simplified three-dimensional geometric model comprising a safety injection T-shaped pipe through CFD software, dividing grids through a hybrid grid technology, carrying out the local encryption of a core region, and generating a boundary layer grid, the method comprises the following steps: selecting a VOF multiphase flow model, a k-epsilon turbulence model and a Lee phase change mass transfer model for coupling simulation, setting corresponding boundary conditions and initial parameters, and finally, completing solution method setting through a Coupled algorithm discrete format and an interpolation method, performing adaptive time step strategy solution, accurately capturing key thermal hydraulic parameters such as a temperature field, a velocity field, flow pattern evolution and the like, and obtaining the thermal hydraulic parameters. And a mixing condensation process of a safety injection coolant and a main loop high-temperature coolant or steam under an accident condition is simulated. The method not only reduces the time consumption and cost of traditional experiments, but also improves the prediction precision of key phenomena in reactor safety analysis, provides reliable technical support for emergency cooling strategy optimization of a pressurized water reactor nuclear power plant under a water loss accident or a steam pipeline fracture accident, and has important engineering application value.

The application belongs to the field of aerospace and fluid mechanics, and discloses an aircraft internal and external flow field structure grid division method based on a non-matching interface, which comprises the following steps: decomposing the aircraft shape into two topological subdomains of an external flow field, an inlet duct and an internal flow field of a tail nozzle, and connecting each subdomain through a pair of completely coinciding interfaces; wherein the internal flow field of the inlet duct and the tail nozzle adopts an O-type topological structured grid, the external flow field adopts a C-type topological structured grid, and the nodes of the O-type topological structured grid and the C-type topological structured grid can slide on the interface. The problems that the adaptability of the non-structured grid is poor in the near-wall boundary layer region, the calculation amount is large, and the mixed grid is difficult to maintain the overall field conservation and high precision in the current numerical simulation of the internal and external flow coupling of the complex aircraft shape are solved.

The invention provides a numerical simulation method for the leaching process of a nickel pressurized stirred tank reactor, which comprises the following steps: creating a geometric model of the nickel pressurized stirred tank reactor, adopting a structured-unstructured mixed grid division mode for the geometric model, and performing grid division on a computational domain of the geometric model to obtain a grid file; constructing a multiphase flow numerical model in the reaction kettle; setting process conditions corresponding to the nickel leaching process in the grid file, and coupling and solving the multiphase flow numerical model to obtain simulation data of flow field characteristic indexes in the reaction kettle in the nickel leaching process; constructing a solid model which is scaled down in equal proportion, and scaling the stirring speed and the gas flow based on a similarity criterion; carrying out a water simulation experiment, and measuring entity experiment data of flow field characteristic indexes; comparing the simulation data with the entity experiment data to correct parameters of the multiphase flow numerical model; different process conditions are set in batches, the corrected multiphase flow numerical model is solved in a coupling mode, and simulation data of the leaching process of the reaction kettle under the different process conditions are obtained. The simulation precision can be improved.

The application discloses a scene preprocessing method for fire simulation, and relates to the technical field of building fire simulation, comprising the following steps: calculating three-dimensional thermal power weight by using a fire spread dynamics model, and generating a thermal map of a fire danger area; extracting a main diffusion direction of the fire and each axial anisotropy parameter by using a tensor field generation algorithm, and generating fire grid parameters; constructing a hexahedral leading grid by using a hybrid grid generator, increasing the grid density of the fire danger area, and obtaining an optimized hybrid grid of the fire; and checking the Reynolds number and matching the boundary layer of the optimized hybrid grid of the fire by using a fire feature self-adaptive algorithm, and iteratively correcting to generate a fire simulation correction grid; by using the hybrid grid generator, the application realizes self-adaptive distribution and smooth connection of the grid density of the fire danger area, so that the grid distribution of the fire danger area is accurately matched with the fire spread characteristics.

This invention relates to the field of geophysical exploration technology and discloses a three-dimensional polarizability inversion method based on cross-gradient constraints. The method includes the following steps: acquiring apparent resistivity observation data d_obsr and equivalent apparent resistivity observation data d_obsη; performing hybrid mesh partitioning on the computational domain to generate a hybrid mesh model containing triangular prism elements, tetrahedral elements, and pyramidal elements; and performing three-dimensional resistivity forward modeling based on the hybrid mesh model to obtain the total field potential. This three-dimensional polarizability inversion method based on cross-gradient constraints, by employing a hybrid mesh (combination of triangular prism, tetrahedral, and pyramidal elements) partitioning technique, can accurately fit undulating surfaces, fundamentally eliminating the terrain influence error caused by mesh simplification. Measured data show that the forward modeling response error at steep terrain measurement points can be reduced from 5.1% to 1.5% using traditional methods, effectively suppressing false anomalies and making the anomaly boundary more clearly delineated.

The invention provides a flow characteristic simulation analysis method and system for a ship feed pump, and the method comprises the steps: building a full-flow-channel parameterized three-dimensional model corresponding to a to-be-analyzed feed pump based on the target design parameters of the to-be-analyzed feed pump; based on a self-adaptive grid technology, corresponding grid division processing is executed on different types of computational domains in the full-flow-channel parameterized three-dimensional model, a mixed grid computational domain model is obtained, and the computational domains comprise a rotating domain and a static domain; based on the target physical model, a preset boundary condition, a preset interface processing mode and the hybrid grid computational domain model, executing unsteady transient calculation processing, and obtaining corresponding flow-induced characteristic simulation key data of the to-be-analyzed feed pump in the multi-working-condition coupling solving process; and according to the flow-induced characteristic simulation key data, performing multi-physics field coupling characteristic analysis on the to-be-analyzed feed pump to obtain a flow characteristic simulation analysis result. The accuracy of predicting the complex working condition of the ship feed pump is improved.

The invention belongs to the field of aerospace and fluid mechanics, and discloses an aircraft internal and external flow field structure grid division method based on a non-matching interface, and the method comprises the steps: decomposing the shape of an aircraft into two topological subdomains, namely an external flow field, an air inlet channel and an exhaust nozzle internal flow field; the sub-domains are connected through a pair of completely overlapped interfaces; wherein an inner flow field of the air inlet channel and the exhaust nozzle adopts an O-shaped topological structured grid, an outer flow field of the air inlet channel and the exhaust nozzle adopts a C-shaped topological structured grid, and nodes of the O-shaped topological structured grid and nodes of the C-shaped topological structured grid can mutually slide on an interface. The problems that in current complex aircraft appearance internal and external flow coupling numerical simulation, an unstructured grid is poor in adaptability and large in calculation amount in a near wall surface boundary layer area, and a mixed grid is difficult to keep full-field conservation and high precision are solved.

The invention discloses an anti-icing prediction method and system for a bionic super-hydrophobic structure, and the method comprises the steps: obtaining a to-be-simulated bionic super-hydrophobic structure, reproducing the bionic super-hydrophobic structure and a contrast plane through modeling, generating a hybrid grid through finite element processing, and importing the hybrid grid into Fluent; in Fluent, loading an explicit interface capture algorithm of a VOF frame, coupling a continuous surface stress CSS model, setting an axial symmetry computational domain, setting a pressure outlet, a non-slip wall surface and a symmetry axis boundary in the axial symmetry computational domain, and inhibiting fluid backflow; initializing the spherical liquid drop, and iteratively tracking a spreading-retracting-bouncing time sequence of the spherical liquid drop on the bionic super-hydrophobic structure on an explicit interface by adopting a non-iterative transient solver; a phase change solidification model and a Lee evaporation-condensation model are coupled in a VOF frame, the temperature is set to be lower than the icing temperature in Fluent, and the icing delay time of the spherical liquid drops on the surface of the bionic super-hydrophobic structure is predicted according to the spreading-retracting-bouncing time sequence.

The invention provides a coal mine goaf directional drilling grouting slurry diffusion distance prediction method, which comprises the steps of defining a global coordinate system for an operation scene of a goaf, establishing a goaf three-dimensional numerical model, and performing grid division on the goaf and a grouting drilling area by adopting a hybrid grid division strategy; based on an O-shaped ring theory and a key layer theory, establishing a three-dimensional space distribution model of porosity and permeability of the goaf; introducing a free medium and porous medium flow coupled slurry-water two-phase flow theory and a level set method, and establishing a slurry diffusion distance prediction model; the grouting pressure, the grout dynamic viscosity and the porous medium permeability are used as influence factors, the grout diffusion volume is used as a response variable, a three-factor and three-level response surface test is designed, and the optimal parameter combination of all the influence factors and the corresponding prediction result of the goaf grouting grout volume fraction are obtained. The method provides theoretical basis and engineering support for goaf grouting process parameter optimization and goaf water disaster prevention and control.

The invention discloses an underwater target sound scattering rapid forecasting method based on an NURBS hybrid grid and Kirchhoff approximation. The underwater target sound scattering rapid forecasting method comprises the following steps: establishing a geometric model by adopting NURBS parameters; generating a parameterized grid for the geometric model through a node insertion algorithm, identifying and combining overlapped vertexes in units caused by overlapping of control points, correcting the units containing the overlapped vertexes into triangular units, and generating a hybrid grid containing the triangular units and quadrilateral units; according to the incident wave direction and the normal vector of the calculation unit, judging whether the unit is located in a sound wave illumination area or not, and recording the illuminated unit to form an effective integral area; based on Kirchhoff high-frequency approximation, constructing an area component expression of a scattering sound field potential function of the rigid target under a far-field condition; a plate element method is adopted, the area component expression is converted into algebraic operation of vertex coordinates on each unit in the effective integral region, and the scattering contribution value of each unit is calculated; and traversing all the effective integral region units, and calculating the target intensity.

This invention provides a method for aerodynamic optimization design of wind tunnel profiles, belonging to the field of wind tunnel profile technology. This invention identifies high-gradient feature points by extracting the curvature distribution of profile features, generates a hybrid mesh using a graph-driven adaptive topology reconstruction algorithm, performs flow field calculations based on the hybrid RANS-LES turbulence simulation method, solves the control equations using a high-precision shock capture format coupled with a WENO limiter, and performs adaptive mesh refinement. It adjusts the coordinates of profile control points using a topological potential-based asymptotic optimization algorithm, and determines whether to output the optimization results or return to iterate again by judging whether the aerodynamic performance evaluation parameters meet the convergence criteria. This solves the technical problem of low optimization efficiency and difficulty in converging to the optimal solution caused by the disconnect between mesh generation, flow field calculation, and profile adjustment in the aerodynamic optimization process of wind tunnel profiles.