48 results about "Steady state simulation" patented technology

The invention discloses a dynamic simulation modeling method for a compressed air energy storage system based on AMESIM and application, and belongs to the technical field of compressed air energy storage.The method comprises the steps that firstly, system indexes are determined, based on the system indexes, a system technological process diagram is designed, main equipment and auxiliary equipment are selected, and design point parameters of the main equipment and the auxiliary equipment in the energy storage and release stage are determined; then, according to the equipment model selection result, sub-models of all elements in the air circulation loop and the heat storage and exchange loop are selected in the AMESIM; thirdly, calibrating and verifying each main equipment sub-model by utilizing main equipment characteristics and model selection parameters, and building a steady-state simulation model of the compressed air energy storage system; and then, constructing a dynamic simulation model based on the steady-state model, and carrying out dynamic simulation verification and evaluation. According to the method, the co-simulation model integrating thermodynamics, fluid mechanics, control theory and mechanical dynamics can be quickly built, and the method has the advantages of being high in model modeling precision, high in multidisciplinary coupling calculation capacity, high in simulation efficiency and the like.

The invention discloses a fan mechanism modeling and optimizing method and system based on a neural network, and the method comprises the steps: building a model of a wind energy utilization coefficient and a thrust coefficient of a fan, and carrying out the steady-state simulation, so as to obtain a two-dimensional relation table model of the wind energy utilization coefficient and the thrust coefficient, establishing a fan aerodynamic model based on the two-dimensional relation table model; respectively establishing a fan transmission chain system model and a fan blade and tower coupling model based on the nonlinear pneumatic torque Tr and the nonlinear air thrust Ft in the fan aerodynamic model to obtain a complete fan mechanism model; and collecting actual operation data of the fan, analyzing the deviation between the fan mechanism model and the actual operation data of the fan based on the neural network, and correcting the deviation through the neural network to obtain an optimized fan mechanism model. According to the invention, the precision of fan modeling can be improved.

The invention relates to the technical field of switching power supplies, and discloses a bilateral modulation control method capable of realizing reverse operation of an LLC resonant converter of a ZCS. Comprising the following steps: deducing time domain expressions of converter operation stages Pr and Or under the influence of parasitic inductance Ls, calculating by using a time domain model to obtain zero current turn-off of a primary side switch of the converter in a full working frequency and load range, and designing a bilateral modulation controller. According to the method, zero-current turn-off of a primary side switching tube is realized; from the perspective of a steady-state simulation waveform, the turn-off current error is less than 1A, so that the switching loss is effectively reduced, the energy loss of the converter in the reverse operation process is reduced, and the overall operation efficiency is further improved; the voltage peak of a primary side switching tube can be reduced; by reducing the voltage spike, the risk that the switch tube is damaged due to overvoltage is reduced, the operation safety and stability of the converter are improved, and reliable operation of the whole system is guaranteed.

The invention relates to an importance degree analysis method and device based on characteristic parameters of a large break water loss accident. The method comprises the following steps: constructing a reactor type steady-state simulation model of a target nuclear power station and a transient model of the large break water loss accident; determining characteristic parameters according to the accident acceptance criterion, the accident response program table, the accident sequence and the nuclear power station system response; generating a plurality of groups of random samples based on the parameter range of the model, and constructing an accident feature database covering the accident under various working conditions by using the plurality of groups of random samples as input conditions and combining the feature parameters; according to the model simulation data, in combination with the characteristic parameter data under various working conditions, constructing a target agent model of the accident among the characteristic parameters under different working conditions; and based on response analysis of the target agent model, analyzing the importance degree of the feature parameters in the target agent model, and sorting according to the influence degree of the feature parameters on the accident response. The method can better guarantee the safe operation of the nuclear power station.

The present invention relates to the technical field of engine simulation. Disclosed are a precision evaluation method and apparatus for an engine simulation model, and an electronic device, which are used for providing a technical solution that improves the precision of an engine simulation model to better support the design, optimization and application of engines. The method comprises: acquiring target parameter simulation data and target parameter test data of an engine; determining the target parameter simulation data and the target parameter test data to be target parameter steady-state simulation data, target parameter steady-state test data, target parameter transient-state simulation data and target parameter transient-state test data; on the basis of the target parameter steady-state simulation data and the target parameter steady-state test data, determining the steady-state precision of target parameters; using a plurality of prediction algorithms to determine a fitting degree evaluation result and a similarity evaluation result of the target parameters under each prediction algorithm; and using a grey relational analysis method to determine the transient-state precision of the target parameters.

The invention provides a natural gas pipeline network hydraulic parameter inversion calculation method based on a starfish optimization algorithm, which optimizes the hydraulic parameters of a steady-state and transient simulation model of a natural gas pipeline network by combining the global exploration and local development mechanism of the starfish optimization algorithm, and comprises the following steps: collecting basic data of the pipeline network; simulation model constraint conditions are established, a natural gas pipeline network steady-state simulation model and a transient simulation model are constructed, a starfish optimization algorithm is adopted for hydraulic parameter inversion calculation, and finally natural gas pipeline network steady-state simulation and transient simulation parameter inversion calculation results are output. According to the natural gas pipeline network hydraulic parameter inversion calculation method based on the starfish optimization algorithm, the accuracy of the pipeline network simulation model is improved by optimizing the input parameters in the simulation model, and more accurate support is provided for scheduling and optimization of the natural gas pipeline network.

The present invention belongs to the technical field of electric deicing of aircraft and engines, and discloses a method, device and medium for predicting the non-steady-state process of electric deicing of aircraft, wherein the method first calculates the air flow field and the water droplet field, obtains the external convective heat transfer coefficient and the water droplet impact amount results, and provides external data for the non-steady-state simulation calculation of deicing. During the non-steady-state simulation calculation, the freezing / melting rate and temperature distribution are obtained through the coupled iteration of the exchange boundary, and the ice amount and overflow state are updated according to the freezing / melting rate and temperature distribution. In the coupled iteration of the exchange boundary, two calculation processes of overflow phase change and diversion are included. The calculation results of overflow phase change and diversion are respectively used as the boundary conditions for executing diversion and overflow phase change. The present invention can obtain the instantaneous change results of surface temperature and ice thickness during the deicing process, and provide a theoretical basis for deicing effect analysis and electric heating deicing strategy design.

The application discloses an air insulation structure verification method and device based on surface flashover voltage calculation, a terminal equipment and a storage medium, and belongs to the technical field of voltage testing. The method comprises the following steps: obtaining an original structure parameter set; establishing a three-dimensional model according to the original structure parameter set; performing steady-state simulation on the three-dimensional model to obtain an initial electric field distribution; correcting the initial electric field distribution according to surface roughness to obtain a first corrected electric field distribution; performing transient simulation on the three-dimensional model to obtain a surface charge density distribution; correcting the first corrected electric field distribution according to the surface charge density distribution to obtain a second corrected electric field distribution; accumulating the volume with a second corrected electric field value not less than a preset gas critical ionization field strength to obtain a critical volume; and calculating the surface flashover voltage based on the critical volume, and verifying the original insulation structure according to the surface flashover voltage. Therefore, by implementing the application, the problem of inaccurate surface flashover voltage calculation in the prior art can be solved.

The present invention discloses a method and device for simulating a steady-state floating offshore wind farm, as well as electronic equipment. The method comprises the following steps: establishing a wind farm wake model; establishing a wind turbine aerodynamic load model; establishing a wind farm index calculation model; establishing a quasi-static mooring system model; establishing a one-way coupling model between the wind turbine aerodynamic load model and the quasi-static mooring system model; and establishing a one-way coupling model between the quasi-static mooring system model and the wind farm index calculation model, thereby ultimately achieving steady-state simulation of the floating offshore wind farm. The method can effectively simulate the complex interactions between the wind turbine and the mooring system structure, and between the structure and the ocean wind environment, while maintaining a fast simulation speed. This method effectively overcomes the insufficiency of existing simulation methods in meeting the simulation time requirements for floating offshore wind farm control optimization, thereby effectively reducing the time and economic costs of floating offshore wind farm simulation and ensuring the feasibility and reliability of floating offshore wind farm control optimization.

The invention relates to the technical field of self-cooled transformers, and discloses an optimization method and system for a radiator of an oil-immersed self-cooled transformer, and the method comprises the steps: 1, determining the geometric structure size of the radiator, and building a two-dimensional axisymmetric geometric model of the transformer with different radiator arrangement heights; 2, determining computational domain division schemes of different heat transfer areas in the transformer, and performing computational domain subdivision on the two-dimensional cylindrical axial symmetry geometric model to obtain a computational domain division result; 3, CFD simulation setting is carried out on the transformer, and a transformer heat-flow field simulation model is obtained; 4, steady-state simulation calculation is conducted on the transformer heat-flow field simulation model through CFD simulation, the internal temperature and flow velocity distribution of the transformer under the rated working condition are simulated, and the hot-spot temperature and the average temperature of a transformer winding under different radiator arrangement heights are obtained; 5, determining an optimization scheme of the arrangement height of the radiator. According to the method, optimization of the arrangement height of the radiator is achieved, and the overall heat dissipation efficiency of the transformer is improved.

The application relates to the technical field of simulation analysis, in particular to a pipeline leak detection method and system. The method comprises the following steps: based on an initial resistance value of a target pipe network, floating point encoding and floating point number decoding are carried out to obtain a plurality of floating point decoding numbers; the floating point decoding numbers are input into a preset steady-state simulation model of the target pipe network to obtain node flow simulation values and / or node pressure simulation values corresponding to each floating point decoding number; based on the node flow simulation values and a preset first fitness function, a first fitness value corresponding to each floating point decoding number is obtained, and / or, based on the node pressure simulation values and a preset second fitness function, a second fitness value corresponding to each floating point decoding number is obtained; based on the first fitness value and / or the second fitness value, a target resistance value is determined from all the floating point decoding numbers; and the steady-state simulation model is updated based on the target resistance value; and thus pipeline leak detection is carried out. The automatic leak detection of the target pipe network can be realized.

An electric-gas coupling system quasi-steady-state simulation method, device and computer readable medium based on branch compensation method. It relates to the improvement of the simulation method of the electric-gas coupling system. It is suitable for occasions with high real-time requirements and can realize fast approximate quasi-dynamic energy flow calculation. It includes the following steps: 1) in the natural gas system, the "circuit-like" method is used to model the natural gas pipeline in a steady state; 2) using the matrix inverse auxiliary theorem, the node pressure is calculated without considering the change of the gas resistance of each pipeline; 3) calculating the branch flow without considering the change of the gas resistance of each pipeline; 4) calculating the node gas pressure considering the change of the gas resistance of each pipeline. The present application extends the branch compensation method to the natural gas system and is suitable for comprehensive modeling, quasi-steady-state simulation and many other scenes of the electric-gas coupling system. When the branch connection condition changes locally, the node admittance matrix is not recalculated, but an approximate result in the new scene is given based on the original calculation result by using the correction method.

The invention discloses an expansion machine impeller life prediction method based on a variable fidelity agent model, and belongs to the field of turbomachinery life analysis. The method comprises the following steps: establishing a three-dimensional model of a fluid domain and a solid domain according to structural characteristic parameters of a target turbo expander, and after grid division and boundary condition configuration, acquiring flow field data through steady-state simulation of the fluid domain and verifying the accuracy. The maximum stress amplitude is extracted by combining bidirectional heat-fluid-solid coupling transient simulation, and an improved load spectrum is constructed; sampling design is carried out on impeller shape parameters and operation condition parameters, sample point sets are divided according to the high-precision and low-precision simulation time consumption ratio, high-precision and low-precision life data are generated through two-way coupling simulation and steady-state flow one-way coupling simulation, and a data set with a fidelity label is formed. And training the proxy model by using a variable fidelity machine learning algorithm to realize life prediction. According to the method, the calculation cost is remarkably reduced through a high-low precision simulation hybrid strategy, and an efficient solution is provided for impeller service life evaluation and optimization design.

The invention provides an initial guess value model calculation method for steady-state simulation calculation of the overall performance of an engine, and the method comprises the steps: extracting a specific performance parameter conversion table and a thermodynamic calculation independent variable parameter table according to a simulation calculation result of a full-envelope working condition; initial guess value calculation is carried out, and a target variable value is given; assigning a low-pressure conversion rotation speed initial value and calculating a target variable to obtain a calculated target variable value; calculating the target variable deviation of the given target variable value and the calculated target variable value, judging whether the target variable deviation meets the error precision or not, and calculating an initial guess value parameter according to the low-pressure conversion rotating speed initial value if the precision requirement is met; and if the precision requirement is not met, correcting the low-pressure conversion rotating speed to obtain a corrected low-pressure conversion rotating speed value, and repeating the steps until the low-pressure conversion rotating speed value with the target variable deviation meeting the error precision is obtained. And according to the low-voltage conversion rotating speed value, interpolating to obtain a specific performance parameter conversion table, and calculating an initial guess value parameter.

This invention relates to a brake disc optimization method, device, and medium based on four-factor constraints. The method includes: obtaining the mass of a target brake disc; establishing a model with an undercarriage structure based on the parameters of the target brake disc, and obtaining the maximum limiting temperature of each part; performing optimization design without exceeding the original mass to obtain the optimized brake disc; performing CFD steady-state simulation to calculate the steady-state cooling pump air ratio; when the maximum temperature is lower than the maximum limiting temperature, determining whether it meets the preset optimization target based on the steady-state cooling pump air ratio; performing CFD transient simulation analysis on candidate brake discs to calculate the transient cooling pump air ratio; when the maximum temperature is lower than the maximum limiting temperature, determining whether it meets the optimization target based on the transient cooling pump air ratio; if so, the target brake disc is the preferred brake disc. Compared with the prior art, this invention solves or partially solves the problem that existing brake disc optimization methods lack constraints during the optimization process, leading to unsatisfactory optimization.

The present invention discloses a system for realizing steady-state and dynamic simulation of the entire process of intelligent decision-making for a heating system, comprising: multiple basic model libraries for storing relevant equipment components, equipment parameters, simulation parameters, and connection types; a simulation model establishment module for selecting and connecting graphical component modules from the model library, inputting equipment structure and characteristic data, and establishing steady-state simulation models and dynamic simulation models; a simulation verification module for verifying model accuracy using a control variable method and modifying corresponding structural parameters according to the error size to ensure that the error is within a reasonable range; a host computer module for real-time data transmission with the simulation unit, real-time display of simulation images, simulation process monitoring, and parameter adjustment; and a simulation application module for issuing simulation control instructions and simulation parameter data. The present invention meets the data requirements for refined analysis of intelligent decision-making such as operation scheduling, fault diagnosis, and planning and design, and improves simulation efficiency and accuracy.

The invention discloses a system modeling method for hydrogen production through water electrolysis of a proton exchange membrane and ammonia synthesis through cryogenic air separation. The system modeling step comprises the step of establishing four mutually connected subsystem models, including a solar photovoltaic power generation subsystem model, a water electrolysis hydrogen production subsystem model, a cryogenic air molecule system model and a synthesis ammonia subsystem model. The invention provides a process for producing hydrogen by electrolyzing water through a photovoltaic-driven proton exchange membrane electrolytic cell, producing nitrogen by cryogenic air separation and coupling ammonia synthesis, so that ammonia-heat co-production is realized, the production efficiency and sustainability of green ammonia are remarkably improved, and a feasible scheme is provided for producing ammonia from renewable energy sources. The steady-state simulation of proton exchange membrane electrolytic cell hydrogen production and deep cooling air separation cooperative ammonia production based on solar photovoltaic driving is realized. The simulation model method can quickly predict the system performance at low cost, provides a quantitative basis for reactor structure optimization and working condition adjustment, further reduces a large amount of time and economic cost consumed by engineering trial and error, and improves the efficiency of system design optimization.

The application relates to the technical field of hydrogen production by water electrolysis, and particularly provides a method and system for establishing a simulation model of an alkaline water electrolysis hydrogen production system, which comprises the following steps: establishing dynamic mathematical models of an electrolytic tank subsystem and an auxiliary subsystem of the alkaline water electrolysis hydrogen production system; connecting the models of the electrolytic tank subsystem and the auxiliary subsystem according to the input-output relationship of the system, taking the gas-liquid two-phase flow work medium flow as the input, taking the temperature and pressure of the work medium at the outlets of the subsystems as the output, performing simultaneous solution, and obtaining the model of the alkaline water electrolysis hydrogen production system; performing steady-state simulation by using system design parameters, and in the case of passing the consistency verification, building a PID control module, and determining the control strategy of the simulation model of the alkaline water electrolysis hydrogen production system. The application realizes the dynamic simulation of the changes of internal physical parameters and external performance of the electrolytic tank under various working conditions by analyzing the component models of the alkaline water electrolysis hydrogen production system and establishing the dynamic mathematical models of the components.

This invention belongs to the technical field of high-field magnet structure design, specifically involving an adaptive selection method for simulation type in pulse magnet structure design. The method includes: establishing a model of the pulse magnet; using a circuit model to calculate the actual current waveform of the magnet at the required power supply voltage; importing this waveform into an electromagnetic finite element model to calculate the peak electromagnetic load of the magnet; applying this load as a single step load to the structural finite element model; extracting the stress-time curve of each target component; and extracting the fundamental component of this curve using Fourier transform to determine the natural vibration frequency of the component. ω m Perform a Fourier transform on the actual current waveform to determine its fundamental component. ω i If all target components ω m All are greater than N × ω i If a steady-state simulation evaluation is selected, then this invention can solve the problem of the lack of a standardized operating system in the existing pulse magnet structure design that can reasonably use static analysis results to approximate transient analysis results.

The invention discloses a method for predicting the longitudinal force of a tire based on finite element transient simulation. The method comprises the following steps: carrying out pure longitudinal slip simulation in finite element simulation software to obtain finite element simulation data, respectively carrying out steady-state simulation under a small slip rate and transient simulation under a large slip rate, and extracting a simulation calculation result; randomly generating a group of magic formula model parameters, and calculating an effective slip rate in combination with a slip rate sequence extracted by longitudinal slip scanning under a large slip rate; calculating a transient longitudinal force, an error between the transient longitudinal force and a simulation transient longitudinal force, and an error between the longitudinal force under a small slip rate and the simulation longitudinal force; optimizing and outputting the error between the transient longitudinal force and the simulated transient longitudinal force and the optimal parameter of the magic formula model when the error between the longitudinal force and the simulated longitudinal force under the small slip rate is minimum; and substituting the initial slip rate sequence into the optimized model, and calculating a steady-state longitudinal force. According to the prediction method, the longitudinal force of the tire can be predicted by using a small amount of simulation data, and the precision is high.

The invention provides a steady-state simulation method and system for rapidly determining the height difference of the liquid levels of two oil tanks and a medium, and belongs to the technical field of commercial vehicle oil supply. The method comprises the steps that the volume ratio is calculated, the stable state condition is set as that the liquid levels of the two oil tanks synchronously descend with the fixed liquid level height difference, and the net oil outlet flow ratio is equal to the volume ratio; converting the liquid level height difference corresponding to the stable state into a pressure difference of the two oil tanks, and setting the pressure difference as a simulation boundary condition; the method comprises the following steps: calculating the net outlet oil flow ratio of two oil tanks in an initial full oil state and the net outlet oil flow ratio of two oil tanks in an empty oil extreme state of a small oil tank through simulation, judging that a stable state exists when the volume ratio is between the two net outlet oil flow ratios, and searching a target pressure value through an iterative algorithm by taking pressure values corresponding to the initial full oil state and the extreme state as intervals; the net oil outlet flow ratio of the two oil tanks obtained in simulation calculation is equal to the volume ratio of the two oil tanks; and obtaining a stable liquid level height difference according to the found target pressure value. The method can quickly determine the liquid level height difference of the double oil tanks.

The invention discloses a method for correcting singular points of a steam turbine transient stress field simulation finite element result, electronic equipment and a computer readable storage medium, and relates to the technical field of steam turbine stress calculation. During steady-state simulation of the steam turbine, singular points are often ignored, so that the calculation result of the stress value of the steam turbine is too large and is the calculation result influencing the service life. According to the method, the singular points are corrected by using the K nearest neighbor algorithm and the inverse distance weighting method, and the singular points caused by unreasonable grids, constraints or structures in finite element simulation can be effectively eliminated. The situation that large numerical values of singular points cover the change of a real stress field, and consequently the accuracy of the whole simulation result is affected is avoided. The method is mainly used for correcting the stress value of the singular point.

The invention provides a thermal management type combined power device control law design method and device, and belongs to the field of aviation electromechanics. The method provided by the invention comprises the steps of establishing a mathematical model for a core component of the thermal management type combined power device, constructing an initial steady-state simulation model in combination with a flow, pressure and energy conservation relationship, and correcting the initial steady-state simulation model to obtain a fidelity steady-state simulation model; establishing a transient simulation model on the basis of the fidelity steady-state simulation model, fusing modal switching logic, a fuel supply strategy, a control target selection rule and a system safety boundary, and designing a basic control law; optimizing control parameters of the transient simulation model by adopting a particle swarm optimization algorithm by taking fuel control PID parameters of the transient simulation model as optimization objects and taking mode switching time, system overshoot and power turbine exhaust temperature as optimization indexes, and updating the optimized parameters to the transient simulation model to obtain a control parameter of the transient simulation model; and obtaining a transient simulation model of the thermal management type combined power device.

The present invention discloses a method and system for evaluating the uniformity of exhaust gas from an SCR reactor of a low-speed diesel engine of a ship, and relates to the technical field of SCR reactors, including: constructing a geometric model of an exhaust gas flow domain, and meshing the geometric model of the exhaust gas flow domain; performing steady-state simulation calculations on the exhaust gas flow field in the SCR reactor, and extracting the airflow velocity, ammonia mass fraction, and unit grid area data of a set cross section at the inlet of the first layer of catalyst in the SCR reactor; comparing the airflow velocity or ammonia mass fraction data of the unit grids of all surfaces of the cross section with the relationship between the area-weighted average value and the standard deviation of the set multiples, and obtaining the total area of ​​the unit grids that meet the conditions; and forming an exhaust gas uniformity evaluation scheme by satisfying the set area ratio as the evaluation criterion for the uniformity of the airflow velocity distribution or ammonia concentration distribution of the cross section. The present invention has clear evaluation indicators, can solve the problem that the relative uniformity deviation evaluation standard cannot truly reflect the quality of the simulation results, and has simple implementation steps.

The invention discloses a simulation verification method for the defrosting performance of a vehicle and a related product, and the method comprises the steps: building a simulation model of the vehicle which comprises a to-be-defrosted part; processing the simulation model to obtain a simulation grid, wherein the simulation grid is provided with a simulation constraint condition; steady-state simulation is conducted on the flow field of the simulation grid based on the simulation constraint condition, a simulation result is obtained, and steady-state simulation is used for enabling the flow field to be gradually converged to tend to be steady in the simulation process through the simulation constraint condition; and based on the simulation result, the defrosting performance of the to-be-defrosted component is determined. Therefore, the development period and the development cost can be effectively reduced, and the evaluation efficiency of the defrosting performance of the vehicle is improved.

This application provides a method and apparatus for designing control laws for a thermally managed combined power unit, belonging to the field of aerospace electromechanical systems. The method includes: establishing mathematical models for the core components of the thermally managed combined power unit; constructing an initial steady-state simulation model by combining flow rate, pressure, and energy conservation relationships; revising the initial steady-state simulation model to obtain a faithful steady-state simulation model; building a transient simulation model based on the faithful steady-state simulation model, incorporating mode switching logic, fuel supply strategy, control target selection rules, and system safety boundaries, and designing a basic control law; employing a particle swarm optimization algorithm, using the fuel control PID parameters of the transient simulation model as the optimization object, and using mode switching time, system overshoot, and power turbine exhaust temperature as optimization indicators to optimize the control parameters of the transient simulation model; updating the optimized parameters to the transient simulation model to obtain a transient simulation model of the thermally managed combined power unit.

The embodiment of the invention relates to a spring valve stability judgment method considering fluid force, which comprises the following steps: determining a total fluid force calculation model of a valve core according to structure parameters and working condition parameters of a spring valve, deducing a steady-state fluid force calculation model and a transient fluid force calculation model according to the total fluid force calculation model, and constructing a nonlinear dynamic model; constructing a steady-state simulation model of the spring valve, performing steady-state simulation on a flow field of the spring valve based on the steady-state simulation model, and fitting to obtain a steady-state force coefficient of the valve core; constructing a transient simulation model of the spring valve, and performing transient simulation on the opening and closing dynamic process of the valve core by using the transient simulation model to obtain a transient fluid force coefficient curve; and constructing a dimensionless state-space equation based on the nonlinear dynamic model, the steady-state force coefficient and the transient fluid force coefficient curve, performing stability judgment on the spring valve by utilizing the dimensionless state-space equation and a stability criterion, and determining an unstable flow interval. According to the embodiment of the invention, the stability of the spring valve can be systematically judged.

The invention discloses a gas emptying concentration distribution simulation calculation method for water electrolysis hydrogen production equipment. The method mainly comprises the following steps: establishing a three-dimensional model according to the actual gas emptying pipeline size 1: 1 of a corresponding equipment frame pipeline of a water electrolysis hydrogen production workshop; extracting and establishing an external flow field model of the gas discharge pipeline based on the pipeline model and the discharge space outside the pipeline, and using the external flow field model for follow-up gas discharge flow field simulation analysis; and importing the external flow field model into simulation software, and respectively carrying out steady state simulation calculation on the hydrogen and oxygen emptying pipelines to obtain a gas emission concentration distribution cloud chart. According to the method, the actual size and structure of the emptying pipeline are considered, meanwhile, the atmospheric environment condition is set, steady-state operation is carried out under the accurate initialization condition, the overall model calculation amount is small, and a basis is provided for stable operation of hydrogen production equipment and gas emptying concentration analysis.

The embodiment of the invention provides a wind noise prediction method of a vehicle, the vehicle and a storage medium. The method comprises the steps of obtaining first voice definition of a position where a target object in a first vehicle is located, a first vehicle structure parameter of the first vehicle and a second vehicle structure parameter of a second vehicle; performing vehicle body external flow field steady-state simulation on the first vehicle and the second vehicle to obtain first aeroacoustic source distribution of the first vehicle and second aeroacoustic source distribution of the second vehicle; constructing a quantization parameter model based on the first aeroacoustic source distribution and the second aeroacoustic source distribution; and performing wind noise prediction on the second vehicle based on the second vehicle structure parameter and the quantization parameter model to obtain a wind noise prediction result. The technical problem of low wind noise prediction efficiency in related technologies is solved.

The invention discloses a method and a device for simulating a fault shutdown transition process of a centrifugal pump under a cavitation condition, and relates to the technical field of numerical simulation of fluid machinery, the method comprises the following steps: establishing a water body model of the centrifugal pump; performing boundary naming and grid division on the water body model to obtain a grid model; performing single-phase flow steady-state simulation calculation based on the grid model to obtain a single-phase flow steady-state simulation result; a multi-phase flow model is constructed, a single-phase flow steady-state simulation result is used as a cavitation calculation initial flow field, cavitation steady-state simulation calculation is carried out, inlet pressure boundary conditions are dynamically adjusted, and a cavitation steady-state simulation result is obtained; constructing an impeller angular velocity time-varying function, and performing shutdown transition process simulation transient calculation by taking the cavitation steady-state simulation result as an initial flow field to obtain a shutdown transition process simulation transient calculation result; and repeating the simulation iteration process to obtain a final shutdown transition process simulation result. According to the invention, the simulation precision of the fault shutdown transition process of the centrifugal pump is improved.