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How to deal with cad-geometry

A simple step-reader is integrated in cgx. It can deal with 2D sections containing points and lines. You might start with such a file and sweep it in the 3rd dimension to create your geometry.This is the approach which i use most often to generate my models. For complicated models you should consider to use a tet-mesher like NETGEN [4] which can read step and generates quite nice tet-meshes. You can read this (abaqus)-meshes with cgx and combine it with cgx-geometry and meshes. Then create your boundary conditions etc. But you can also create a so called stl-file based on your cgx-geometry and feed it to external meshers. The following section explains how to do that:

In general hexahedra-elements perform better that tets but if the mesh should be derived from a cad-geometry it is often more convenient to create a tetrahedra mesh as to modify or rebuild the geometry to make it meshable with hexahedra-elements. In this case the user can mesh the surfaces with unstructured triangles and export them in the stl-format (see ''send'') as a basis for an auto-mesher [4]. The following steps have to be done:

Figure 9: CAD-file meshed with tet-elements using NETGEN
\begin{figure}\epsfig{file=halter.eps,width=9cm}\end{figure}


next up previous contents
Next: Remarks Concerning Duns and Up: Tips and Hints Previous: How to run cgx   Contents
root 2010-07-31