Questions tagged [finite-element-analysis]

Anything related to finite element analysis or finite element methods (FEMs), i.e. a number of advanced numerical analysis techniques for finding approximate solutions of differential equations. FEMs are heavily used in many branches of engineering, for example to simplify the design phase of a project.

The methods transform the differential equation into a weak form over the problem domain, which is then discretized by a set of elements (e.g. a triangle-shaped plate or quadrilateral shells). This allows for a per-element approximation of the solution and an assembly of global quantities by local quadrature rules, resulting in a possibly nonlinear system of equations. For large problem statements, finding a solution might require parallel computing strategies.

Many areas of engineering profit from these techniques, e.g. solid and structural mechanics on various time- and size-scales, electrical field theory or diffusion problems, and there are plenty of (free) software solutions available. In scientific computing, users regularly need to extend the method by custom element formulations or new solution procedures, which is often done in fortran, c++ or python.

See also the Wikipedia page on FEMs.

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Finite difference - wave equation - boundary conditions and setting things up

I am working on a project that has to do with solving the wave equation in 2D (x, y, t) numericaly using the central difference approximation in MATLAB with the following boundary conditions: The general assembly formula is: I understand some of…
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Summing squared area changes from Voronoi cells given area of triangles in 3D?

I have a list of triangles in 3D that form a surface (ie a triangulation). The structure is a deformed triangular lattice. I want to know the change in area of the deformed hexagons of the voronoi tessalation of the lattice with respect to the rest…
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fenics: applying force on a particular point

I am a newbie in fenics and finite element methods. I try to implement a method to estimate the elasticity parameters (young modulus and poisson ratio) of a deformable object. What I want to do is this: An object fixed from the bottom(as a start a…
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Tetrahedralization from surface mesh of thin-walled object

I need to generate a tetrahedral (volume) mesh of thin-walled object object. Think of objects like a bottle or a plastic bowl, etc, which are mostly hollow. The volumetric mesh is needed for an FEM simulation. A surface mesh of the outside surface…
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Write multi columns list on the fly

Hi i am writing a list as follow: > l = [[10312, -13.069404602050781], [10313, -28.044403076171875], > [10314, -32.765602111816406], [10315, -47.353294372558594], > [10312, -63.069404602050781], [10313, -78.044403076171875], > [10314,…
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Trying to use matplotlib with ABAQUS. Getting error involving dateutil

I am wondering if any of you use matplotlib for your python codes that are coupled with ABAQUS. I'm using ABAQUS 6.12, which has python 2.6. Also, I'm using Windows 64 bit. I have downloaded matplotlib, but when I import matplotlib onto the…
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Matlab solution for implicit finite difference heat equation with kinetic reactions

I am trying to model heat conduction within a wood cylinder using implicit finite difference methods. The general heat equation that I'm using for cylindrical and spherical shapes is: Where p is the shape factor, p = 1 for cylinder and p = 2 for…
wigging
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What should I do, in material calibration, when Abaqus model fails to converge and etc.?

A common practice that I do when building models in Abaqus, is to fit the material property. For example, I try out all the possible material properties and look at the surface deflection given by the model, and then find out the one that matches…
Yuxiang Wang
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Efficiently searching arrays in FORTRAN

I am trying to store the stiffness matrix in FORTRAN in sparse format to save memory, i.e. I am using three vectors of non-zero elements (irows, icols, A). After finding out the size of these arrays the next step is to insert the values in them. So…
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Getting started with Finite Elements methods

There is a cubic block of fractured rock; the question is: how to simulate fluid flow from top-side to down-side or left-side to right-side? Is FEA (FEM,...) the only practical solution? If so for the question above in its simplest…
Developer
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Rearranging a vector in matlab

I'm writing a code for adaptive finite element method in 1d. I have an interval let say [0,1] and in first iteration I have a mesh, x=0:.25:1 and in second iteration I would like to divide the second and last segment in 3 and 5 segments. So the…
REZA
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Using tetrahedron to model deformable objects in OpenGL

I want to render a mesh made up of tetrahedron in OpenGL because I am trying to implement animation which requires the use of the 'finite element method'. As a novice of OpenGL, I am not quite sure how to approach this. So far, I have come across…
Aaron
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FEM: computing edge values from continuous function (Whitney p-forms)

I'm writing a Finite element method based on Whitney p-forms, where the solution coefficients are defined on edges and faces. For example, the electric field can be approximated as vec(E) = sum e_i vec(W)_i where the sum is over the edges (e.g. 3…
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How to get damping matrix for structural model in FE analysis

I need to implement in C a method of obtaining transient solution Rdm of damped FE models based on modal results R for a structural model (imported CAD geometry) defined with hysteretic (structural) damping, the method is also available in Matlab by…
Piotr
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saving the results of post_process function using sfepy Library

I'm trying to calculate the effective conductivity of a two-phase material using the sfepy library in Python. The material consists of two phases with different conductivity values. I have a 2D mesh representing the geometry of the material stored…
Yasi
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