39 results about "Finite element stress analysis" patented technology

There is provided a method and apparatus for determining the risk of rupture of a blood vessel using a set of 2-D slice images obtained by scanning the blood vessel. The invention includes elements and steps for generating a mesh model of the blood vessel using the set of 2-D slice images, conducting finite element stress analysis on the mesh model to calculate the level of stress on different locations on the mesh model and determining the risk of rupture of the blood vessel based on the calculated levels of stress on different locations on the mesh model.

A method for determining the risk of rupture of a blood vessel using an appropriate set of 2-D slice images obtained by scanning the blood vessel, the method comprising: generating a mesh model of the blood vessel using the set of 2-D slice images; conducting finite element stress analysis on the mesh model to calculate the level of stress on different locations on the mesh model; and determining the risk of rupture of the blood vessel based on the calculated levels of stress on different locations on the mesh model.

Improved methods and systems for defining and creating simulated rigid bodies in finite element analysis are disclosed. One or more rigid finite elements in a finite element model are designated for forming one or more simulated rigid bodies (RBs). Each simulated RB comprises an arbitrary number of rigid finite elements connecting to one another in an arbitrary shape. Each simulated RB is created by locating all of the elements embedded in the model through shared node or nodes. A procedure of using element definition as a guide to set up an array of node flags, each node flag for one node such that all RBs defined in the model can be located efficiently. Once all RBs have been located, each unique RB is defined as a unique list of connected rigid finite elements.

In another preferred form of the present invention, there is provided a method for determining the risk of rupture of a blood vessel using an appropriate set of 2-D slice images obtained by scanning the blood vessel, the method comprising:generating a mesh model of the blood vessel using the set of 2-D slice images;conducting finite element stress analysis on the mesh model to calculate the level of stress on different locations on the mesh model; anddetermining the risk of rupture of the blood vessel based on the calculated levels of stress on different locations on the mesh model.In another preferred form of the present invention, there is provided an apparatus for determining the risk of rupture of a blood vessel using an appropriate set of 2-D slice images obtained by scanning the blood vessel, the apparatus comprising:apparatus for generating a mesh model of the blood vessel using the set of 2-D slice images;apparatus for conducting finite element stress analysis on the mesh model to calculate the level of stress on different locations on the mesh model; andapparatus for determining the risk of rupture of the blood vessel based on the calculated levels of stress on different locations on the mesh model.

The invention relates to a safety state evaluation method for a large-diameter thick-wall part of a high-parameter unit, and the method comprises the steps: arranging a stress measurement point at thelarge-diameter thick-wall part of the unit, carrying out the field stress testing through an online stress monitoring device, and obtaining the actual measurement data; based on a finite element stress analysis method, carrying out numerical simulation calculation on the stress level of the position where the measuring points are arranged, and obtaining simulation data; carrying out linear fitting on the simulation data and the actual measurement data, and carrying out verification and correction on the simulation data and the actual measurement data to enable the deviation between the simulation data and the actual measurement data to be within a range of + / -5%; setting the stress early warning value of the on-site online stress monitoring device to be 80% of the allowable stress value of the corresponding material at the same temperature; setting a stress early warning value of a finite element stress analysis method to be 85% of an allowable stress value of the corresponding material at the same temperature; and obtaining a safety state evaluation result of the large-diameter thick-wall part based on the evaluation index F value. According to the invention, accurate evaluationof the safety state of the large-diameter thick-wall part is realized.

The invention discloses a method for calculating the joint bearing capacity of multiple spatial complex pipe columns. The method comprises the following steps: establishing a finite element model of the multiple spatial complex pipe columns; performing finite element analysis on the finite element models of the multiple spatial complex pipe columns to obtain a finite element analysis result; and performing regression fitting on the finite element analysis result to obtain a calculation formula of the ultimate bearing capacity of the spatial column node. According to the method, a calculation formula of the ultimate bearing capacity of the multiple spatial complex pipe column joints is fitted, and a reference can be provided for engineering design through calculation according to the formula.

Improved methods and systems for defining and creating simulated rigid bodies in finite element analysis are disclosed. One or more rigid finite elements in a finite element model are designated for forming one or more simulated rigid bodies (RBs). Each simulated RB comprises an arbitrary number of rigid finite elements connecting to one another in an arbitrary shape. Each simulated RB is created by locating all of the elements embedded in the model through shared node or nodes. A procedure of using element definition as a guide to set up an array of node flags, each node flag for one node such that all RBs defined in the model can be located efficiently. Once all RBs have been located, each unique RB is defined as a unique list of connected rigid finite elements.

The invention relates to a structural material rapid selection method based on finite element analysis, and belongs to the field of mechanical structure finite element analysis. Two relational expressions of Young's modulus of a structural material satisfying corresponding design requirement conditions are deduced respectively through a theoretical relationship among a load, displacement and a stiffness matrix in a finite element theory, and a material meeting requirements can be selected rapidly by means of simple calculation and judgment through the two relational expressions, so that a rapid selection way is provided for the selection of the structural material. The method comprises the following specific implementation steps: firstly, solving a maximum displacement and corresponding j-order inherent frequency when the structural material is any certain known material through the finite element analysis; secondly, bringing a solving result and a corresponding design requirement into corresponding expressions, and calculating a material Young's modulus satisfying a requirement; and lastly, selecting an appropriate material according to the result. The method disclosed by the invention has the advantages of rapidness, small calculated amount, easiness in solving and the like.

The invention relates to the technical field of petroleum and natural gas exploration, and discloses an exploration method for oil and gas reservoirs controlled by strike-slip faults, including: describing the strike-slip structural form of the target area through three-dimensional seismic data, and finding specific reservoir-controlling parts in the strike-slip fault; Low-velocity, low-resistivity, and low-density body locations are used to determine deep hydrocarbon sources; further, through rock mineralogical analysis and geochemical means to confirm whether there is a deep heat source in the formation corresponding to the reservoir-controlling part obtained by S1; further, through surface exploration and combined with The well logging and logging data of the existing wells confirm that there are oil and gas shows in the parts with deep heat sources obtained by S3; finally, through the finite element stress analysis, the favorable oil and gas enrichment areas are determined. Through the above steps, the location of the oil and gas reservoir controlled by the target strike-slip fault can be accurately determined.

The invention discloses a computer aided design (CAD) system for a composite type earth pressure shield cutter head, which belongs to the field of computer software. In the system, Solidworks 2008 is developed secondarily based on Visual Basic 6.0 to realize parametric modeling, and UDEC 4.0, MATLAB 7.0 and ANSYS Workbench 10.0 are called to perform automatic analysis and optimization. The system comprises a user input module, a basic function module, a performance analysis module, an optimization design module and a historical data management module. A user inputs geological parameters and technical requirements, and the system automatically combines theories of opening design, cutting tool type selection and cutting tool layout to perform basic configuration design, cutting tool geology adaptability type selection, cutting tool optimization layout, cutter head finite element stress analysis and cutter head structural parameter optimization design on the composite type earth pressure shield cutter head so as to obtain an optimal three-dimensional design result of a target cutter head, and the system automatically stores the data input by the user and a corresponding design result. By the CAD system, a corresponding relation between the geological parameters and key design parameters of the cutter head can be quickly established, and design reliability and design efficiency can be improved.

The invention relates to a mesoscopic structure design method guided by force flow, which comprises the following steps: 1) establishing a finite element analysis model according to the load and boundary conditions under the actual working condition of the part, and obtaining the finite element stress analysis result; The stress information required for force flow visualization is obtained from the meta-stress analysis results; 3) The force flow lines are generated according to the stress information and the number of interpolation points N; 4) The mesoscopic structure is generated guided by the force flow lines. Compared with the prior art, the present invention considers the force flow information under the actual working conditions of the parts, and can generate different force flow lines according to different force flow definitions, and then generate mesoscopic structures with different arrangements, realizing the same geometry of the parts Under the different internal mesoscopic structure design, the specific strength and specific stiffness of the part structure are improved.

A method for solving and visually displaying a self-defined stress function belongs to the technical field of finite element numerical simulation mechanical strength analysis. The present invention aims at the difficulties that may be encountered when general-purpose finite element software performs comprehensive analysis of specific theoretical requirements on the stress state of components under different working conditions, and is characterized in that: based on MSC.Marc / Mentat 2005 software, different working conditions For the finite element stress analysis results of the lower member, by extracting the stress component data of the unit integration points under various working conditions, set and calculate and solve the custom stress function data outside the general finite element software, and realize the custom stress function data by means of data replacement. Visualization of stress function data on MSC.Marc / Mentat 2005 finite element model. The advantages and positive effects of the present invention are that the realization method is simple and easy, the application range is wide, and the use limitation of professional software or secondary development can be avoided.

The invention discloses a method for calculating a load of a wing integral fuel tank. The method comprises the steps of first calculating loads which fuel is subjected to in the X-direction, Y-direction and Z-direction by utilizing the principle that the loads can be overlaid linearly in the structure on-line elastic range; respectively calculating pressure distribution of each end face of the inner wall of the fuel tank under unidirectional overloads; finally overlaying pressure generated by each unidirectional overload, and obtaining pressure distribution of the wing fuel tank; establishing a wing fuel tank local detail finite element model in a full-aircraft overall finite element model, adding the pressure load of each end face of the fuel tank to the finite element model, applying corresponding working condition aerodynamic loads, and performing finite element stress analysis to obtain finite element stress result under each working condition. Under the conditions that the aircraft wing integral fuel tank is not pressurized and an inertial load of the fuel to the fuel tank exists, the method for calculating the load of the fuel tank is used for intensity assessment, and the load which the fuel tank is subjected to can be reflected genuinely.

The invention discloses a bearing simplifying method in finite element simulation analysis. According to the method, a three-dimensional gap unit is used for simplifying finite element analysis of an angular contact bearing, and a three-dimensional model of the bearing is drawn in three-dimensional mapping software solidworks. The bearing model is imported into finite element pre-processing software Hypermesh. An outer ring and an inner ring of the bearing are divided into hexahedral meshes. The outer ring and the inner ring of the bearing are connected through the three-dimensional gap unit. The spring stiffness K in the gap unit is worked out through a bearing radial stiffness calculation program. The finite element model is exported from the Hypermesh, then the finite element model is imported into engineering simulation software ANSYS, and mechanical calculation is conducted. According to the method, the calculation amount of finite element analysis can be simplified, the efficiency can be increased, and the calculation accuracy cannot be damaged.