Using GiD the mesh may be generated in different ways, depending on the needs of each project. The two basic types of body-fitted meshes are the structured2 and the unstructured mesh. For volumes only there is one additional type, the semi-structured3 mesh.
For all these types of mesh a variety of elements may be used (line ones, triangles, quadrilaterals, circles, tetrahedra, hexahedra, prisms, spheres or points). In this tutorial you will become familiarized with the mesh-generating combinations available in GiD. _____________________________________________________________________
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2 A structured mesh is one in which each internal node is connected to a constant number of elements.
3 A semi-structured volume mesh is one in which you can distinguish a fixed structure in one direction, i.e. there is a fixed number of divisions. However, within each division the mesh may not be structured. This kind of mesh is only possible for topologically prismatic volumes.