213 results about "Grid file" patented technology

The invention discloses a method for simulating the blade flutter boundary of an aviation turbine engine, which is based on the principle of energy law and adopts a weak coupling method to design a flutter forecasting method, thus obtaining the blade flutter boundary of the engine by pneumatic damping value. The method comprises: first, a solid model of a blade is set up; then, modal analysis is carried out on the blade; after that, a flow field model of the blade is set up; the vibration displacement of the linear interpolation blade can be obtained, grid files needed by flow field analysis are generated by adopting multilayer dynamic mesh processing, a dynamic mesh module is invoked to obtain the parameters in the flow field, pneumatic damping is acquired under every working condition, and finally, the flutter boundary can be obtained. Based on the one-way weak coupling, the method greatly simplifies the calculation, saves the calculation cost, and can realize the pneumatic damping calculation under any frequency and different flow field states, thus having good engineering applicability.

The invention discloses a simulation method for the wind pressure coefficient of a reflection plane antenna panel, and the method comprises the steps: firstly building an antenna panel geometric model through ProE software; secondly importing the geometric model into preposed dividing grid software ICEM-CFD, building and computing a flow field region range, and carrying out the grid dividing of the flow field region; thirdly enabling a grid file to be imported into flow field solving software FLUENT, carrying out the computing and solving through a series of settings, and obtaining the wind pressure distribution of the antenna panel; finally exporting the computing and solving result of the FLUENT, and compiling a MATLAB program to solve the blocked mean wind pressure coefficient value. The method solves a problem that a conventional reflection plane antenna is short of related tunnel test data, and determines the blocked wind pressure coefficient values of the antenna panel under various conditions through a software simulation method. The method can provide the visual flow field information, is low in cost, can carry out the repeated operation, facilitates the control of the change of simulation environment conditions, and is complete in result collection.

The invention aims to provide a river water quality prediction method. The method includes the steps that a specific boundary of a to-be-predicted river is depicted; a .kml format file of the predicted river boundary is converted into a point; the WGS 1984 coordinates of the point are converted into coordinates with meter as the unit; the converted to-be-predicted river boundary point position coordinates are stored; grid division is carried out on the predicted river by using CVLGrid1.0 software, and the divided predicted river grid is exported; a grid file of the to-be-predicted river is imported into an EFDC-Explorer; on the basis of establishing a hydrodynamic model, a water quality model of the predicted river is established; real-time monitored flow and water quality data of the flow boundary of the predicted river are imported into the water quality model, the water quality distribution situation of the to-be-predicted river is simulated within a period of time, and water quality prediction of the to-be-predicted river is achieved. The method is unique, easy to operate and apply, accurate in prediction effect and beneficial to ecological environment protection of rivers, and has remarkable economic and social benefits.

The invention discloses a mining area automatic semantic segmentation method in remote sensing image in the technical field of automatic target detection and depth learning, characterized in that: thespecific steps are as follows: 1, establishing a training sample set: acquisition of Remote Sensing Images of Mining Areas, and artificial delineating the boundaries of the mining area, forming a Boundary Grid File, 448*448 being generated by ArcGIS, 512*512 fishing nets of two scales, the remote sensing image of the mining area being cut in batches by using the two generated fishing nets to generate image blocks of different sizes as input data of the depth learning network, and the boundary files of the mining area grid in the image being cut through the fishing nets to generate boundary files corresponding to each mining area image block as label data of the network. The invention adopts a hybrid network Den-Res Net can abstract the extracted features while preserving the integrity offeatures, which can be used to solve the redundancy problem of Dense Net network, and the method has high efficiency, automatic semantic segregation and high accuracy.

The present invention provides a stirred tank reactor simulation method based on an immersed boundary method. The method includes: a preparation phase including determination and setting of calculating parameters, generation of fluid grid files, generation of Lagrange mark point information, and preparation of calculating resources; numerical calculation: setting boundary conditions of computational domains and solving velocity fields and temperature fields based on fluid grids; combining with a discrete element method to achieve an interface analytic simulation of two-phase flow of particle flow, wherein the immersed boundary method is directly employed to apply non-slip boundary conditions to particle surfaces; a post-processing phase, and outputting information of each Euler mesh and information of each particle after a simulation is completed. According to the characteristics of different boundaries, in the calculation, the mixed immersed boundary method is employed to process, and the mass numerical simulation of turbulent flow in the stirred tank reactor is achieved through combination of large eddy simulation and high performance parallel computing technology. The simulation method may be applied to simulation of turbulent flow and simulation of solid particle suspension in the stirred tank reactor and the like.

The invention discloses a grid parallel preprocessing method based on MPI. The grid parallel preprocessing method based on the MPI comprises the following steps: giving a partition number of grids in a computation area; starting MPI multiprocessing, setting a process number; judging whether the process number is equal to the partition number; opening grid files if the process number is equal to the partition number, reading grid cell information files by a main process, initially and averagely assigning the grid cells to each process, creating an adjacent array of each process; otherwise, restarting the MPI multiprocessing; invoking ParMETIS by each process to divide the grids; reading the grid cell information by blocks into the array through each process, setting an index position of the array; looping through the grid cell information files by each process, judging whether the difference of subtracting the index position number of the array from the array length is less than the length of the grid cell information; if the answer is yes, reading data of the grid cell information files and filling the array with the data; otherwise, assigning array elements to the grid cells; judging whether the partition number of the grid cell is equal to the process number; if the answer is yes, storing the grid cell information into a process file; otherwise, keeping judging circularly.

A method and an apparatus for authenticating location-based services without compromising location privacy, which comprises a comprehensive solution that preserves unconditional location privacy when authenticating either range queries using three authentication schemes for R-tree and grid-file index, together with two optimization techniques, or k-nearest neighbor queries using two authentication schemes for R-tree and Voronoi Diagram index.

The invention relates to a system for the transmission of mass high-energy physical experimental data. The system comprises a multipath source data scanning module, a data buffer area module, an efficient polling module, a transmitting optimization module, a transmitting module, a data buffer area automatic release module, efficient receiving modules, data validation modules, receiving optimization modules, storage modules, a user management configuration module and a monitoring module, wherein the multipath source data scanning module, the data buffer area module, the efficient polling module, the transmitting optimization module, the transmitting module and the data buffer area automatic release module are located in a source-end efficient transmitting module, and the efficient receiving modules, the data validation modules, the receiving optimization modules and the storage modules are located at the destination end. The invention also relates to a method for the transmission of the mass high-energy physical experimental data, and the method comprises three steps. According to the system and the method, the multipath parallel transmission of the high-energy physical experimental data is realized based on a GridFTP (Grid File Transfer Protocol), and the function of each module of the system can be configured through a user management configuration interface, so that the graphic monitoring of stages during the process of system operation and no mutual interference during the process of multipath transmission are realized, and the problems of single transmission destinations, single configurable items, system instability, difficulty in extension and the like of the existing data transmission system are sovled.

The invention provides an automatic simulation analysis method and device based on STAR-CCM +. The method comprises the following steps: starting the STAR-CCM + according to a preset automatic script;reading the grid file to build a simulation analysis model; reading the parameter file to perform parameter setting on the simulation model; performing simulation operation analysis according to thesimulation analysis model after parameter setting is completed; and carrying out post-processing on the operation result to generate a result file. According to the invention, the automation of simulation analysis can be realized, the working efficiency is improved, the cost is reduced, and the accuracy of a simulation result is improved.

The invention discloses a method for analyzing swing high-speed jet characteristics of an underwater engine nozzle, and belongs to the field of fluid mechanical engineering. The implementation methodcomprises the following steps of: through establishing a geometric model of an underwater solid rocket engine nozzle, establishing a fluid calculation domain, carrying out geometric optimization on aninterface of the two fluid calculation domains, setting an interface between the calculation domains for data transmission to achieve simulation of the swing working condition of the nozzle, carryingout grid division on the fluid domains in a partitioned mode, carrying out grid independence verification, and obtaining the optimal grid number; importing the obtained final grid file into a FLUENTsolver, setting boundary conditions, an adopted calculation model and a calculation method, and carrying out solving; carrying out numerical simulation analysis and post-processing on a numerical calculation result. The rocket engine nozzle swing high-speed jet flow characteristic is accurately simulated and analyzed, the nozzle swing high-speed jet flow rule and mechanism can be easily disclosed,a theoretical basis is provided for the engine nozzle structure design of underwater powered missile launching, and the actual engineering application problem of underwater powered missile launchingis solved.

The invention provides a radial oil film bearing dynamic mesh updating method based on Fluent. The method comprises the following steps that (1), a bearing oil film mesh file is established; (2), a UDF control macroprogram in Fluent software is compiled; (4) a data file obtained in the third step is treated with an Excel tool; (5) fluid calculation software Fluent is started, the mesh file is imported, a UDF program is mounted, and UDF control conditions are set; (6), flow field calculation is controlled through a UDF dynamic mesh program; and (7) whether a bearing neck center track is convergent or not is judged. According to the radial oil film bearing dynamic mesh updating method based on the Fluent, the problem that due to the fact that the length-width ratio of bearing oil film meshes is too large, mesh distortion is prone to occur in the dynamic mesh moving process is solved, and equal-interval distribution, in the circumferential direction, of mesh lines in the radial direction before and after the moving process is guaranteed. When the method is used for calculating node coordinates of dynamic meshes, the mesh lines are always perpendicular to the bearing neck surface, the meshes are not prone to distortion, accumulated errors of mesh calculation are avoided, and the bearing performance calculating speed is increased.