User:Egm6321.f10.team2.oztekin/Newwwwwww

=Problem 6.3:Using Calculix to reproduce Beede's Models=

Calculix is an open source program that we can solve our FEA problems. Bconverged is a really good provider of calculix that would offer engineers work between different platforms. After downloading calculix software from bconverged we will have two modules of calculix and text editor called SciTE. These two modules that belongs to calculix are $$ \displaystyle\mathit{cgx} $$ and $$\displaystyle\mathit{ccx} $$. In the first module of calculix we can design our solid models and define boundary conditions on it. The solver,crunchix (ccx), is solver and post processor.Lets start building models that are presented by Beede's.Beede's examples. Also this cite and more information is provided by Dr. Vu-Quoc in our EML5526 FEA class page. Class page

FEA BEAM PART 1:Getting started
As a first step we have to open SciTE text editor that is a place where we type our commands and view our models. To run it


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$$  \displaystyle [Start] \Rightarrow [All Programs]\Rightarrow [bConverged]\Rightarrow [SciTE] $$
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Here are some information about SciTE editor.



This is very important to understand that we will use two typing methods to type our commands. This i a very beautiful property of calculix. We can type in text editor and that 'run ' all of the codes in it or we can type directly by clicking on the graph screen and execute the code by hitting enter.


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$$  \displaystyle [open SciTE]\Rightarrow [File]\Rightarrow [Save As]\Rightarrow [beam.fbd] $$
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The step presented above is a essential step. Because you can not run the codes without saving!!!


 * Type these codes into your SciTE editor. Then hit F10 key or click tools--post processor to run.
 * pnt p1 0 0 0
 * pnt p2 100 0 0
 * line l1 p1 p2 25



Let's get familiar with our codes.


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$$  \displaystyle \begin{matrix} pnt \Rightarrow name & x coord. & y coord. & z coord. & \end{matrix} $$
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$$  \displaystyle \begin{matrix} line \Rightarrow name & start point & end point & division & \end{matrix} $$
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 * Proceed with expanding commands in text editor and creating four lines and five nodes. We are partially creating this big line because if we had constructed the line in one step the mesh would have been arbitrary. So to avoid arbitrariness we are doing more steps. We want equal divisions among mesh elements.


 * Here how we can view our model in different aspects. In the area surrounded by thin black surface use this properties of mouse.


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$$  \displaystyle \begin{matrix} LMB & rotate \\ MMB & zoom\\ RMB & pan \end{matrix} $$
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 * While cgx window is active it means that we are working in 'interactive mode.' Type these commands while cgx window is active.
 * plot pa all
 * plus la all


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$$  \displaystyle \begin{matrix} plot & n(nodes) & e(elements) &f(faces) & p(points) & l(lines) & s(surfaces) & b(bodies) & all(set name) \end{matrix} $$
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$$  \displaystyle \begin{matrix} plus & n(nodes) & e(elements) &f(faces) & p(points) & l(lines) & s(surfaces) & b(bodies) & all(set name) \end{matrix} $$
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Commands are same for plot and plus. But there is a slight difference between them. Plot command plots only one type of entity removes other entities from graph screen but plus command adds entities to the other entities that are already visual in graph screen.


 * Type seta lines l l1 l2 l3 l4
 * swep lines sweplines tra 0 10 0 10
 * seta surfaces s A001 A002 A003 A004
 * swep surfaces swepsurfaces tra 0 0 1 1


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$$  \displaystyle \begin{matrix} seta & type & elements. in.set & \end{matrix} $$
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$$  \displaystyle \begin{matrix} swep & set & fx &fy & fz &  tra& dx & dy & dz \end{matrix} $$
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As we see above we have created body from swepping surfaces, surfaces from swepping lines. When we create a high order entity lower order entities will be kept in order to define the high order one. For example if we create surface lines and points will be kept.

After constructing the body now we can mesh our body.We have different kinds of elements for 1D,2D,and 3D meshes. Type these commands in interactive mode.
 * elty all he8
 * mesh all
 * plot m all


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$$  \displaystyle \begin{matrix} elty & set & meshtype \end{matrix} $$
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$$  \displaystyle \begin{matrix} mesh & set \end{matrix} $$
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By using different types of views we can get different aspects of our mesh and other entities.

FEA BEAM PART 2:Exporting mesh,loads,and boundary conditions
In this section again we start with our text editor and open beam.fbd. Now we are updating written codes in it. New codes
 * seto beam
 * pnt commands
 * line commands
 * sets and swep codes
 * setc beam
 * defining and setting up mesh

Between seto and setc commands we have defined set named beam and we put all of the entities in this general set. Also we have defined other sets just before we did in the last section.If we hit the F10 key and run our new codes beam.msh will be created automatically.Opening beam.msh yields following



As we see above two sets defined in this document. Node and element sets. Looking at element sets we can see that elements are 3D elements with 8 nodes. The style of presenting data and storing is calculix convenience.



Here we have defined another set named fixed to assign fixed nodes in it. View the appropriate section of the beam and type quadd fixed while in interactive mode. Then press r and move the cursor down and press r to create select box. Be careful to create select box that can fit all tha nodes that we are interested in. Press a to active mode a then press n to select nodes in the box. You will see the node properties in the output section and by pressing q we will have finished our job.

As mentioned in the article we have two different boundary conditions. We have defined fixed dots where we will apply restriction on their displacement. Also turn the view to see faces and viewing elements,we found element '751'.And we have applied pressure force its upward surface. And we applied two force vectors on its two nodes.

We can show element correspondence with their families.

FEA BEAM PART 3
In this section as you see in the figure we created new text file but with an extension .inp. This means that now we are using ccx commands. Generally start with '*'. First we are taking input parameter from *.msh and *.123 documents. Between STEP and ENDSTEP we are also defining material properties and selensting Solve and Post process tabs from the tools bar we can find stresses along the beam.



FEA BEAM PART 4

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$$  \displaystyle Deformed Shape $$
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$$  \displaystyle \begin{matrix} Part & Of  & Animation \end{matrix} $$
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$$  \displaystyle \begin{matrix} Y stress & At  & Portion \end{matrix} $$
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