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977 results about "Fluid field" patented technology

Unsteady flow field dimension reduction and prediction method fusing physical modeling and deep learning

The invention discloses an unsteady flow field dimension reduction and prediction method fusing physical modeling and deep learning, and belongs to the technical field of computer-aided fluid mechanics analysis. According to the method, firstly, a modal coefficient reflecting global dynamics is extracted from an unsteady flow field by using a DMD, and meanwhile, low-dimensional feature representation of a potential space is learned from a flow field snapshot through CVAE; the two types of features have complementarity in physical and statistical meanings, and the complex dynamic evolution law of the unsteady flow field is more effectively represented through the low-dimensional features constructed in a combined mode. On the basis, an LSTM model is used for carrying out time sequence modeling on the joint features, and high-precision prediction of future evolution of the flow field is achieved. The hybrid modeling method provided by the invention improves the dimensionality reduction efficiency and prediction precision of a high-dimensional nonlinear unsteady flow field while keeping physical consistency, and is suitable for intelligent simulation and rapid prediction tasks in a complex flow scene.
Owner:ZHEJIANG UNIV

Titanium alloy surface electroplating control method

ActiveCN120866916ACellsData setMetallurgy
The invention belongs to the technical field of electroplating process optimization, and particularly discloses a titanium alloy surface electroplating control method which comprises the following steps: dynamically generating a hanger posture configuration scheme based on workpiece three-dimensional contour data acquired in real time; a bubble distribution image and electroplating liquid flow field data are synchronously collected, and a bubble-flow field coupling feature set is generated through multi-modal fusion; performing real-time linkage adjustment on the rotation speed and the swing amplitude of the workpiece according to the coupling feature set; after electroplating is completed, plating thickness, edge integrity and surface defect data are collected, and a multi-source plating data set is formed by combining workpiece position information; historical data and real-time data are integrated to carry out hanger layout adjustment judgment, and hanger spacing dynamic reconstruction optimization is started when adjustment is needed. According to the method, multi-parameter cooperative control and closed-loop quality optimization in the electroplating process are achieved, the uniformity and integrity of a titanium alloy workpiece coating are remarkably improved, and generation of bubble related defects is effectively restrained.
Owner:BAOJI TOPUDA TITANIUM IND CO LTD

Centrifugal pump performance optimization method and device, computer equipment and storage medium

The invention provides a centrifugal pump performance optimization method and device, computer equipment and a storage medium, and belongs to the field of centrifugal pump design. The method comprises the steps that a parameterized model of a centrifugal pump impeller is established to define the geometrical shape of the centrifugal pump impeller, a design space is determined, and a plurality of sample points are generated; for each sample point, performing computational fluid dynamics simulation, adjusting inlet pressure, monitoring a ratio of simulation lift to rated lift, determining critical cavitation pressure corresponding to the sample point, and storing flow field data to construct a data set; training an agent model by using the data set; the lift, the efficiency and the critical cavitation pressure serve as targets, design variables serve as optimization variables, performance is evaluated through an agent model, global optimization is conducted through a multi-target optimization algorithm, and a target design scheme is selected from a Pareto solution set obtained through optimization. Therefore, the centrifugal pump performance under different design variables can be quickly and accurately predicted, multiple targets are effectively balanced, and a comprehensive optimization solution is provided.
Owner:XI AN JIAOTONG UNIV

Quick prediction method, system and equipment for two-dimensional viscous compressible flow field of gas compressor and medium

ActiveCN121835521AGeometric CADDesign optimisation/simulationViscous compressible flowImpeller
The invention belongs to the field of aero-engines and turbines, and provides a quick prediction method, system and device for a two-dimensional viscous compressible flow field of a gas compressor and a medium, and the method comprises the steps: obtaining CFD simulation data of a two-dimensional blade profile of the gas compressor under multiple working conditions, and carrying out the preprocessing to obtain a standardized training data set; on the basis of the data set, constructing a hybrid neural network model which takes a blade profile geometric parameter and an operation condition parameter as input and takes a two-dimensional viscous compressible flow field as output; combining mean square error, gradient loss and physical consistency loss based on RANS equation residual error to construct a total loss function, and performing end-to-end training on the model; during reasoning, to-be-predicted parameters are input into the trained model according to the same preprocessing mode, and then a flow field prediction result can be rapidly output. According to the method, the problems of long consumed time, low precision and poor consistency of traditional CFD simulation can be solved, millisecond-level flow field prediction is achieved, high precision and high physical consistency are achieved, and the method is suitable for efficient optimization design of the blade profile of the gas compressor.
Owner:TAIHANG NATIONAL LABORATORY

Quantitative diagnosis method for injection-production regulation non-equilibrium degree based on fluid potential energy

The invention discloses an injection-production regulation imbalance quantitative diagnosis method based on fluid potential energy, and the method comprises the steps: extracting a streamline track space coordinate sequence and corresponding point oil reservoir parameters based on a dynamic permeability field, a pressure field and an injection-production streamline field; constructing a three-dimensional fluid potential energy field model in the injection-production unit, and dividing dominant seepage, a retention zone and a transition zone based on the injection-production unit through potential energy gradient tensor; establishing a seepage potential index LS by taking the flow line penetrating pore volume as a stability weighting factor and combining the potential energy gradient intensity; on the basis of LS sorting, a potential energy-volume two-factor accumulation curve is constructed, the development non-equilibrium degree is represented through curve form parameterization, and the envelope area of the accumulation curve is calculated and used for representing the oil reservoir flow field development non-equilibrium degree and the development effect of each type of injection-production unit. According to the method, fluid potential energy and a two-factor cumulative distribution concept are introduced into computational logic, and unified and quantitative characterization of an oil reservoir flow field and an injection-production unit is realized in combination with a seepage mechanism of the injection-production unit.
Owner:CNOOC ENERGY TECHNOLOGY & SERVICES LTD

Vacuum circuit breaker opening and closing dynamic characteristic calculation method, device, equipment and medium

The invention relates to the field of vacuum circuit breakers, in particular to a vacuum circuit breaker opening and closing dynamic characteristic calculation method, device and equipment and a medium. Establishing a three-dimensional geometric model of the pole-mounted vacuum circuit breaker arc extinguish chamber and the moving and static contacts; setting material attributes for each part in the three-dimensional geometric model; constructing a multi-physics field coupling system; the area where the moving contact is located is divided into movable grids, and the grid density of the moving contact and the grid density of the static contact dynamically change along with time; and performing multi-field coupling transient solution according to the three-dimensional geometric model, the multi-physical field coupling system and the movable grid to obtain the dynamic characteristics of the vacuum circuit breaker. The electromagnetic field, the thermal field, the fluid field, the structure field and the circuit are subjected to full coupling analysis, multi-physical field strong coupling dynamic simulation of the whole opening and closing process is achieved, and the dynamic characteristics of the whole opening and closing process can be accurately calculated.
Owner:STATE GRID SICHUAN ELECTRIC POWER CORP ELECTRIC POWER RES INST

Method for evaluating uniformity of outlet flow field of integrated composite flow channel of combustion chamber and turbine guider

The invention discloses a combustion chamber and turbine guider integrated composite flow channel outlet flow field uniformity evaluation method, and belongs to the technical field of gas turbine pneumatic design. The method comprises the steps that a geometric model of a combustion chamber and turbine guider integrated composite flow channel is built, a combustion chamber function section and a guider pneumatic section are fused through integral pneumatic modeling to form a continuous flow channel, a front section adopts a diffusion structure to form a low-speed combustion area, and a rear section adopts a gradually-shrinking channel to achieve gas accelerated expansion; performing three-dimensional cold-state flow field numerical simulation by adopting a structured grid division and delay separation vortex simulation technology; flow parameters including total pressure, Mach number, airflow angle and vorticity are extracted from the cross section of a flow channel outlet, conversion from a Cartesian coordinate system to a polar coordinate system is carried out, and a uniformly distributed aerodynamic parameter field is reconstructed by using an interpolation algorithm; the directional coupling degree is calculated based on the spatial correlation of the pressure gradient vector and the vorticity vector, and the vortex-pressure coupling entropy production index representing the overall aerodynamic loss of the flow channel is established in combination with the pressure pulsation intensity and the vorticity concentration ratio. According to the method, a three-dimensional evaluation system is constructed by integrating circumferential and radial non-uniformity and entropy production parameters, and accurate quantitative evaluation of flow characteristics and uniformity of the combustion chamber and turbine integrated structure is realized.
Owner:CHINA UNITED GAS TURBINE TECH CO LTD

Simulation method for particle motion and interaction behavior within continuous casting mold

The present invention relates to the technical field of steel metallurgy process simulation, and specifically relates to a simulation method for particle motion and interaction behavior within a continuous casting mold. The simulation method comprises the following steps: acquiring mold parameters and establishing a model; performing fluid domain volume extraction and structured mesh division on the model; importing the mesh model into simulation software and performing iterative solution; establishing injection points for argon bubbles and inclusions within the mold, compiling and calculating the flotation removal of argon bubbles and inclusions at a steel-slag interface, the capture thereof at a solidification front, and collision-aggregation, and performing coupled computation; and post-processing the simulation results to obtain the flow field, temperature field, solidified-shell distribution, and discrete-phase motion behavior within the mold at different time points. The method of the present invention enables analysis of the motion and interactions of discrete-phase particles such as argon bubbles and inclusions within the mold, thereby accurately predicting the distribution of the particles in the molten steel and the solidified shell.
Owner:UNIV OF SCI & TECH BEIJING

Rotary machinery system performance evaluation and optimization method and system based on system negentropy conversion rate

PendingCN121278881AGeometric CADDesign optimisation/simulationViscous dissipationNegentropy
The invention provides a rotating mechanical system performance evaluation and optimization method and system based on system negentropy conversion rate, and the method comprises the following steps: carrying out the numerical simulation of a flow field of a rotating mechanical system through a computational fluid mechanics method, and obtaining the parameters of the flow field; calculating a viscous dissipation entropy yield, a turbulent dissipation entropy yield and a wall entropy yield in the fluid domain based on the flow field parameters; the total entropy yield of the system is obtained through the volume fraction and the wall area fraction of the whole fluid domain; converting the input power of the rotating machinery into an equivalent negentropy flow, and calculating the negentropy conversion rate of the system for evaluating the effective utilization degree of the input power; and evaluating the performance of the rotating machinery system based on the negentropy conversion rate, and identifying a key area of energy loss. According to the method, the negentropy conversion rate result is applied to structural design optimization, running state diagnosis and energy efficiency adjustment of the rotating machinery, and online calculation and dynamic visualization can be realized in combination with real-time monitoring data.
Owner:SUZHOU MANGRUFU EQUIPMENT TECHNOLOGY CO LTD +1

A numerical simulation method and device for the collapse of a single cavitation bubble near a wall coupled with boundary motion

The present invention discloses a method and device for numerical simulation of near-wall single cavitation collapse coupled with boundary motion, comprising: step 1, introducing a physical model of a near-wall single cavitation into a pre-constructed external flow field to obtain a corresponding flow field physical model; step 2, meshing the flow field physical model; setting initial conditions and flow field boundary conditions, and setting a time step that meets the calculation requirements; step 3, setting specific calculation parameters for solving the flow field process, and introducing a fluid volume method to capture the gas-liquid interface; step 4, applying wall vibration in the form of a user-defined function to simulate the cavitation dynamics behavior under vibration impact. The present invention takes into account the influence of wall vibration in the numerical simulation process by coupling boundary motion, and realizes the simulation of the dynamics behavior of near-wall single cavitation under vibration impact conditions. On this basis, the influence of conditions such as vibration frequency on the cavitation collapse process can be further explored, providing theoretical guidance for optimized cavitation suppression design.
Owner:ZHEJIANG UNIV

Simulation method for corresponding relation between baffle tongue position and flow field of semi-spiral suction chamber

The invention discloses a simulation method for a corresponding relation between a baffle tongue position and a flow field of a semi-spiral suction chamber, and relates to the technical field of double suction pump design and numerical simulation. According to the method, a three-dimensional flow channel model of multiple groups of baffle tongue reference position parameters is constructed, multi-working-condition simulation and quantitative analysis are combined, a mapping relation model of baffle tongue positions and flow field characteristic parameters is established, and a baffle tongue region vortex generation rule, turbulence dissipation and pressure pulsation characteristics are accurately captured; the optimal baffle tongue parameter interval is determined by combining the flow field uniformity and energy loss minimization principle, the flow loss is effectively reduced, the vortex strength and energy dissipation are reduced, and the flow field uniformity is improved, so that the pump efficiency is improved, the vibration noise and the cavitation phenomenon are inhibited, and the optimal baffle tongue parameter interval is obtained by adopting adaptive grid encryption, a multiphase flow cavitation model and a test verification mechanism. The mapping model is corrected by combining measured data, so that the optimization result can directly guide the baffle tongue design under different working conditions, the research and development period is remarkably shortened, and the physical test cost is reduced.
Owner:SANLIAN PUMP IND CO LTD

Prediction method for fluid excitation characteristics of propeller

The invention discloses a method for predicting fluid excitation characteristics of a propeller, and relates to the field of propeller simulation. The method comprises the following steps: modeling a propeller flow field according to attribute information corresponding to the propeller flow field to obtain a propeller flow field grid model; determining a propeller flow field control equation corresponding to the propeller flow field grid model, and discretizing the propeller flow field control equation by adopting a finite volume method to obtain a discretized propeller flow field control equation; performing propeller hydrodynamic numerical simulation on the discrete propeller flow field control equation based on a delay separation vortex simulation method to obtain speed spatial-temporal distribution and pressure spatial-temporal distribution, and performing decoupling processing on the speed spatial-temporal distribution and the pressure spatial-temporal distribution; and according to the whirling vibration data, the vortex motion data, the decoupled pressure field and the decoupled speed field, the exciting force of the propeller flow field is obtained. The method can accurately reflect the influence of different vortex motions on the excitation characteristics of the propeller and the fluctuation of the velocity field of the propeller.
Owner:CHINA STATE SHIPBUILDING CORP LTD RESEARCH INSTITUTE 719

Large-scale particle flow numerical calculation method based on multi-ball filling

The invention relates to the field of multiphase numerical simulation, and discloses a large-scale particle flow numerical calculation method based on multi-ball filling, and the method comprises the steps: obtaining a fluid domain grid size, a fluid density and a large particle radius; calculating the radius of the small filling ball according to the size of the fluid domain grid; based on golden angle spiral distribution and minimum distance coverage judgment, determining the number and the positions of small filling balls, and generating a large particle model of multi-ball filling; obtaining the background flow field speed of the large particles and the filling small balls in the current time step, and calculating the background flow field speed and drag force of the large particles; updating through iterative calculation to obtain the speed and the position of the large particles and the small filling balls in the next time step; and adding drag force as a source item into a momentum equation to solve fluid motion, and obtaining a fluid computational domain grid speed in the next time step. Accurate numerical simulation of large-scale particles is realized.
Owner:ZHEJIANG SCI-TECH UNIV

Motor fluid field and temperature field iterative coupling method

The invention discloses an iterative coupling method for a fluid field and a temperature field of a motor, which is characterized in that through multi-round data iteration of a flow field and a thermal field, the precision of bidirectional coupling is approached by a one-way coupling process, the computing resource demand is obviously reduced, the computing complexity is reduced, the precision and efficiency are considered, and the method is suitable for rapid thermal design of the motor. The method has the advantages of being high in calculation efficiency, controllable in precision and high in universality.
Owner:JIANGSU RUIKONG ELECTRIC TECHNOLOGY CO LTD

A spiral freezer with multiple circulating flow fields and a method for regulating the same

This invention relates to a spiral quick-freezing machine with multiple circulating flow fields and its adjustment method, comprising a hopper, a conveying system, and an air source; an air guide plate is arranged outside the conveying system, dividing the hopper into an inner and outer section; a partition is arranged outside the air guide plate, dividing the hopper into an upper and lower section; the air source is arranged on the partition, with the air outlet located in the upper section and the air inlet in the lower section; a first air inlet, a second air inlet, a third air inlet, a first air outlet, and a second air outlet are provided on the air guide plate, with the first air inlet, second air inlet, and first air outlet all located above the partition, and the third air inlet and second air outlet located below the partition; a circulating air vent is arranged on the partition near the first air outlet. By setting multiple air vents, two circulating flow fields are formed. Under single-space conditions, the form of the flow field is changed by controlling the opening and closing of the air vents, thereby achieving the selection of a suitable flow field under different operating conditions.
Owner:SIFANG TECH GRP CO LTD

Method, device and equipment for predicting additional mass coefficient and viscous damping coefficient of multi-degree-of-freedom motion of floating body, storage medium and computer program product

The invention relates to the technical field of hydrodynamic analysis of ship and ocean engineering, in particular to a method, a device and equipment for predicting an additional mass coefficient and a viscous damping coefficient of multi-degree-of-freedom movement of a floating body, a storage medium and a computer program product. The method comprises the following steps: performing orthogonal two-dimensional slicing on each plane to generate flow field sampling points based on a floating body three-dimensional geometric model, draft and motion parameters; sampling point coordinates, initial flow field data, geometric contour discrete points, boundary conditions and motion parameters are coded into high-dimensional feature vectors through a learnable matrix, and input matrixes of all planes are constructed; predicting two-dimensional flow field data by adopting a Transform module, fusing multi-plane data through a graph attention network to generate a redundant three-dimensional flow field, and interpolating and complementing object plane missing points; the water pressure and the viscous shear force are divided along the surface area of the floating body, the inertia term and the damping term are decomposed in combination with the single-mode motion equation, the target additional mass coefficient and the target viscous damping coefficient are determined, and the accuracy of floating body hydrodynamic calculation is improved.
Owner:SOUTHERN MARINE SCIENCE & ENGINEERING GUANGDONG LABORATORY (ZHANJIANG)

Device for simulating influence of ditch cleaning ice cover evolution on hydrodynamic parameters and application method thereof

The invention discloses a device for simulating influence of ditch cleaning ice cover evolution on hydrodynamic parameters and an application method thereof, and relates to the technical field of ice water dynamics and hydraulic engineering experiments. The device comprises a low-level water tank, a high-level water tank, a centrifugal pump, a flow valve, a water tank, a steady-flow perforated plate, a ditch cleaning ice cover simulation device, a first water level control grid plate, a second water level control grid plate and a flow field measurement system. According to the invention, three key parameters of ditch cleaning length, ice cover submerging water depth and roughness of the bottom of the ice cover are independently regulated and controlled, and non-contact high-precision measurement is carried out by means of a PIV technology, so that systematic and refined research on hydrodynamic parameters of an ice cover ditch cleaning area is realized. According to the method, researchers can safely and systematically research the influence of a single variable on the ice cover ditch cleaning water power at low cost, and the fundamental bottleneck of traditional field measurement in the research is solved.
Owner:INNER MONGOLIA UNIV OF SCI & TECH

Variable-density low-speed flow mesoscopic numerical calculation method and apparatus

The present invention relates to the technical field of fluid mechanics. Disclosed is a variable-density low-speed flow mesoscopic numerical calculation method, comprising: determining a computational domain, and dividing or reading grid information, fluid parameters and control parameters in the computational domain; on the basis of the read information, allocating arrays, initializing corresponding parameters of the computational domain, and entering a time step loop upon completion; setting boundary conditions, and assigning all boundary macroscopic quantities in a flow field; under a finite volume framework, deriving a numerical flux of the flow field by means of a BGK equation to solve a Navier-Stokes equation of the flow field; calculating pressure and velocity fluxes at cell interfaces of the flow field, and updating boundary macroscopic quantity information on the basis of flux information; determining whether there is an external force, and if so, applying the external force by means of splitting, and updating the boundary macroscopic quantities; determining whether a time step meets a loop condition; if so, re-entering setting boundary conditions, and assigning all boundary macroscopic quantities in the flow field; and if not, outputting flow field data, and ending simulation. The present invention has the advantages of high algorithm accuracy and simple programming.
Owner:SHANGHAI SUOCHEN INFORMATION TECHNOLOGY CO LTD

Modeling method for annular propeller of underwater propeller based on analog simulation

The invention relates to the technical field of underwater propeller modeling, and discloses an underwater propeller annular propeller modeling method based on analog simulation. The method comprises the following steps: constructing an initial blade fluid domain grid model by using a discrete element simulation algorithm based on three-dimensional geometric parameters and material attribute data of an annular propeller; after multiphase flow coupling boundary conditions are applied to the initial model, fluid dynamic load distribution data are obtained through a transient flow field solver; generating a blade deformation characteristic value according to the load data, and if the blade deformation characteristic value exceeds a preset tolerance interval, activating a dynamic grid reconstruction instruction; fluid-structure interaction interface pressure pulsation data is extracted based on the instruction, a stress concentration coefficient is calculated in combination with material attributes, and an abnormal signal is generated when a safety threshold value is exceeded; and when the signal is triggered, the vortex field tracking module is called to update the fluid domain grid model.
Owner:TIANJIN HAOYE TECH CO LTD +1

Method for predicting thermal wear of pump for direct coal liquefaction by considering high-temperature effect

The invention discloses a direct coal liquefaction pump thermal wear prediction method considering a high temperature effect, and belongs to the technical field of fluid machinery and reliability engineering.The method comprises the steps that the high temperature effect is considered, a liquid phase control equation and a solid particle dynamic model are subjected to coupling iteration, and a solid-liquid two-phase flow numerical model is obtained; the method comprises the following steps: performing full flow field modeling on a fluid domain formed by flow passage components of a pump for direct coal liquefaction, and performing grid division on the fluid domain; constructing a heat-flow-solid multi-field coupling calculation system, and solving the solid-liquid two-phase flow numerical model by adopting a large eddy simulation method based on temperature correction and a discrete element method coupling method to obtain information of flow fields and particle fields at all positions in the pump; operation condition parameters are obtained, the thermal wear rate is obtained through a thermal wear rate calculation formula on the basis of flow field and particle field information of all positions in the pump, and the predicted wear amount of the flow passage component is obtained; and the prediction precision and applicability of the wear model are improved.
Owner:HEFEI GENERAL MACHINERY RES INST +2

Centrifugal pump performance intelligent diagnosis method and system based on pressure characteristics

The invention relates to the technical field of centrifugal pump fault diagnosis, and discloses a centrifugal pump performance intelligent diagnosis method and system based on pressure characteristics, and the centrifugal pump performance intelligent diagnosis method based on the pressure characteristics comprises the steps: constructing a flow-machine double-domain theoretical framework, and building a system state evolution equation; structural features are extracted from the centrifugal pump pressure gradient field through a topological data analysis method, and a flow field abnormal mode is recognized; based on the time domain, frequency domain and time-frequency domain characteristics of the centrifugal pump pressure signal, a pressure fingerprint model is constructed, and mechanical fault characteristics are extracted; establishing a causal relationship network between the flow field anomaly and the mechanical fault by using a graph causal inference technology; fusing physical model constraint and data-driven learning, and constructing a knowledge graph hybrid inference engine; constructing an interpretable AI decision system; according to the invention, through the flow and machine fault causal network model, accurate source tracing from symptom expression to root causes is realized, and targeted maintenance decisions are effectively supported.
Owner:HUIMAO ELECTRONIC COMPONENT KUNSHAN CO LTD

Fluid-structure interaction numerical calculation method for controlling flutter of large-span bridge through submerged heaving plate

The invention belongs to the technical field of vibration control, and provides a fluid-structure interaction numerical calculation method for controlling flutter of a large-span bridge by a submerged heaving plate, which is based on computational fluid dynamics software Fluent, utilizes a dynamic grid technology, compiles a UDF secondary development program and embeds the UDF secondary development program into a solver for calculation. The method comprises the following steps: establishing a motion control equation of a rigid main beam-sling-underwater heaving plate coupling system in a wind field, embedding a system motion solving process into Fluent software by utilizing a user-defined function, and realizing system fluid-solid coupling solving by adopting a mode of alternately solving a rigid main beam and a wind field computational domain and simultaneously solving a heaving plate and a water body computational domain. And vertical and torsional motion responses of the controlled main beam are obtained. Compared with a physical experiment, rich information such as movement time history data of the main beam, the heaving plate and a nearby flow field under the condition of various sizes can be conveniently and safely obtained, vibration suppression mechanism analysis can be conveniently carried out, and the research difficulty, cost and risk are greatly reduced.
Owner:DALIAN UNIV OF TECH

Method and system for real-time collection and intelligent fusion processing of polder area multi-site water conservancy data

The invention relates to the technical field of intelligent water conservancy and automatic control, in particular to a polder area multi-station water conservancy data real-time collection and intelligent fusion processing method and system, and the method comprises the steps: a multi-dimensional collection system construction step: collecting time sequence state, fluid field and environment boundary data, and executing time base unified cleaning; an ideal model construction step: constructing an ideal water tank model based on the law of conservation of mass and generating an ideal water level change curve; a parameter injection simulation step: generating a simulation fault water level curve according to injection efficiency attenuation and medium leakage parameters; a double-track difference calculation step: respectively carrying out difference on actual measurement and simulation data and an ideal curve to generate real and theoretical residual vectors; a similarity judgment and control step: calculating sequence similarity to judge a real physical fault or sensor data noise, and generating a fusion control instruction; according to the invention, the technical problem of distinguishing the noise of the sensor from the real physical fault is effectively solved, and false alarm or missing alarm is avoided.
Owner:ZHEJIANG WANBEI ENG SURVEY & DESIGN CO LTD

13-hole probe and fluid velocity vector measuring method and system

The invention discloses a thirteen-hole probe and a fluid velocity vector measurement method and system, and the method comprises the steps: carrying out the partitioning of the thirteen-hole probe according to the physical position of each pressure hole in the surface of a spherical probe; adjusting the angle attitude of the thirteen-hole probe, obtaining multiple groups of calibration data under a known flow field, and calculating an angle coefficient characteristic curve graph of each subarea by using the calibration data; performing dimensionless processing on the pore pressure data of each pressure pore in the known flow field to obtain a dimensionless pressure coefficient for fitting, and establishing a general calculation model; and collecting actually measured pore pressure data of the thirteen-hole probe in the flow field to be measured, positioning the subarea to which the actually measured pore pressure data belongs, and calling the angle characteristic curve of the corresponding subarea in the general calculation model to calculate the flow field parameters of the flow field to be measured. A plurality of pressure holes are formed in the spherical probe and used for receiving airflow in multiple directions, the defect that only airflow in the axis direction of the probe can be received in the prior art is overcome, and large-angle bias flow measurement is achieved.
Owner:NANCHANG HANGKONG UNIVERSITY

Flexible riser vibration response characteristic analysis method

The invention discloses a flexible riser vibration response characteristic analysis method, and relates to the technical field of ocean engineering. According to the method, a flexible riser vibration model is established based on a vibration theoretical model and a fluid control equation for vibration analysis, a theoretical time domain response curve of the flexible riser is obtained through MATLAB calculation, and then a flexible riser three-dimensional simulation model is established in an ANSYS Workbench integrated simulation platform. According to the method, a flexible riser three-dimensional simulation model is constructed, material constitutive parameters, boundary conditions and load application of the flexible riser three-dimensional simulation model are configured, then simulation is performed in an ANSYS Workbench integrated simulation platform by using the flexible riser three-dimensional simulation model, bidirectional fluid-solid coupling analysis is performed by coupling a Fluent flow field system and a Transient Stratum module, the radial displacement time history of the flexible riser under a preset working condition is obtained, and the radial displacement time history of the flexible riser under the preset working condition is calculated. And extracting resonance characteristics of the flexible riser. According to the method, the vibration response characteristics of the deep-sea flexible riser under the influence of internal and external fluids in the service process are accurately obtained, and a foundation is laid for guiding the structural stability of a deep-sea operation system.
Owner:HARBIN ENG UNIV +1

Semi-desorption LBM-DEM method for simulating particle-fluid two-phase flow

The invention provides a semi-analytic LBM-DEM method for simulating particle-fluid two-phase flow, and the method comprises the steps: constructing a semi-analytic LBM-DEM coupling model, enabling the model to firstly determine the range of an expansion domain of particles, and obtaining the information, such as the average fluid velocity, the vorticity, the pressure gradient and the porosity, near the particles through traversing units in the expansion domain; and then, based on a theoretical formula and a semi-empirical formula, calculating the acting force of the fluid on the particles, and correcting a solid collision operator weight coefficient of a particle covering unit according to the acting force, so that synchronous evolution of particle dynamics and flow field distribution is realized. Compared with a classical analysis LBM-DEM coupling method, the method has the advantages that the calculation cost can be remarkably reduced under the condition that the calculation precision is guaranteed, and the method is particularly suitable for particle two-phase flow simulation in complex flow channels such as porous media and fractures.
Owner:WUHAN UNIV

Underwater contra-rotating compressor blade tip leakage flow vibration prediction method and system based on fluid-structure interaction simulation

The invention relates to the field of underwater pressurization, and discloses an underwater contra-rotating compressor blade tip leakage flow vibration prediction method and system based on fluid-solid coupling simulation, and the method comprises the steps: carrying out the division of flow field grids and the division of solid domain grids based on a constructed underwater contra-rotating compressor impeller three-dimensional model; establishing a blade flow field CFD model and a blade solid domain FEA model; aNSYS Fluent software is used for conducting underwater contra-rotating compressor three-dimensional unsteady blade flow field simulation so as to obtain unsteady blade tip leakage flow characteristics of a concerned flow field area; an external data module in ANSYS Workbench software is used for loading the aerodynamic force, obtained through unsteady flow simulation, of the surface of the blade to the surface of a blade solid domain FEA model, transmission of the aerodynamic force load between different blade surface grids is achieved, and one-way fluid-solid coupling is achieved; aNSYS Workbench software is used for conducting underwater counter-rotating compressor blade vibration simulation, vibration response of the blade under the combined action of aerodynamic force and centrifugal force is obtained, and the fatigue life of the blade is predicted based on a fatigue model.
Owner:CHINA NATIONAL OFFSHORE OIL (CHINA) CO LTD +1

Variable reaction degree optimization-based through-flow method and system for reaction steam turbine

The invention discloses a reaction steam turbine through-flow method and system based on variable reaction degree optimization, and belongs to the technical field of steam turbine through-flow design. The method comprises the steps that an initial geometric model of a steam turbine through-flow part and thermal boundary conditions of all stages are obtained; inputting the initial geometric model and the thermal boundary conditions into a flow field solver, and solving a flow control equation to obtain an original flow field solution; constructing a functional taking through-flow efficiency as a target, and deducing an adjoint equation corresponding to the flow control equation; solving the adjoint equation to obtain gradient information of the target functional to each level of reaction degree; inputting the gradient information into a sequential quadratic programming optimizer, and iteratively updating the reactance of each stage by combining the maximum equivalent stress upper limit of the moving blade and the lower limit of the through-flow throat area to generate a variable reactance distribution scheme; and adjusting molded line geometric parameters of each stage of stationary blade and moving blade, and outputting optimized three-dimensional molded line data and a digital model file for numerical control machining. According to the method, the in-stage flow loss is reduced, and the design robustness is enhanced.
Owner:HUANENG (ZHEJIANG) ENERGY DEV CO LTD

Fluid simulation method for semi-welded plate heat exchanger

The invention discloses a fluid simulation method for a semi-welded plate heat exchanger, which relates to the technical field of heat exchanger simulation and comprises the following steps: acquiring porous medium parameters of a porous medium model by using a single-side medium three-dimensional model; performing grid division on the single-side medium three-dimensional model to obtain a grid division result of the single-side medium three-dimensional model; according to the porous medium parameters of the porous medium model and the grid division result of the single-side medium three-dimensional model, preliminary flow field trial calculation is carried out based on a k-omega SST turbulence model, and a preliminary flow field trial calculation result is obtained; fitting processing is carried out based on the preliminary flow field trial calculation result, and a semi-welded plate type alternating current device fluid simulation result is obtained. According to the method, single-side overall pressure drop prediction of the semi-welded plate heat exchanger is achieved, on the basis, the turbulence model is used for predicting the flowing condition of media between the plates, the accuracy of heat exchanger flow field calculation is greatly improved, flowing near the wall faces of the plates is closer to the actual state, and the positive effect on prediction of the performance of the heat exchanger is achieved.
Owner:NORTH CHINA MUNICIPAL ENG DESIGN & RES INST +1

Extra-large-diameter slurry shield deslagging parameter optimization method, system and equipment and storage medium

The invention discloses an ultra-large-diameter slurry shield deslagging parameter optimization method, system and device and a storage medium. The method comprises the following steps that a three-dimensional model is constructed; establishing a motion simulation model; the motion simulation model solves a flow process equation of a slurry fluid phase and a motion control equation of a rock slag particle phase according to the deslagging parameters, so that flow field distribution characteristics and rock slag migration behaviors in the excavation bin and the air cushion bin are obtained; obtaining an evaluation index of the deslagging performance, and judging whether the evaluation index meets a preset requirement or not. According to the method, a fluid phase flow equation and a particle phase motion control equation are solved by utilizing the simulation model, and an interaction mechanism of the slurry and the rock slag is defined, so that simulation is closer to a real situation; and dynamic adaptation of slag discharge parameters with a complex pipe network system and actual construction working conditions is realized. The probability of detention and accumulation of rock slag at the bottoms of the excavation bin and the air cushion bin is remarkably reduced, equipment abrasion is reduced, abnormal tunneling parameters are avoided, and stability and continuity of shield tunneling are guaranteed.
Owner:CENT SOUTH UNIV