Generating the mesh can be the most time-consuming part of FE analysis. To make it easier, FEMdesigner includes 3 ways to make the mesh. In each, elements are created from "regions" of points. For each region edge you can control the amount and shape of the elements within the region.
Method 1: Create regions by picking points on the screen using the mouse. With this method, the region points can be defined in cartesian, cylindrical or polar coordinate systems and can be defined relative to another point. Point coordinates may also be input as expressions with variables, eg. a+(b/2), allowing you to rapidly modify a mesh for different geometries, just by changing the values of the variables.Click here to download Screencam movies of this method.
Method 2: You can also create a CAD line drawing with extra line, curve and arc entities which differentiate plane and solid regions. On importing as a dxf file, drawing errors are fixed, intersections are found, and plane, shell or solid regions are automatically identified and created.
The above two procedures create fast, accurate curved quadrilateral 2D and hexahedral 3D elements and are recommended for simpler structures.
Method 3: You can import a solid model as an IGES file from your CAD or solid modeller application. This is the recommended method for very complex geometries. You still have local mesh control at the surface of the 3D mesh but you also specify a global element size for greater simplicity. These models tend to be quite large so a special solver was developed for them. Click here for more information and examples.
Once the regions are created, they can be manipulated and tweaked in FEMdesigner until the user is happy with the mesh. Restraints, constraints and loads can be applied directly to the regions and will be automatically transferred to the mesh.
If the stresses are beyond the allowable limits then the geometry can be readily altered by moving the points which define the regions and the analysis may be re-run. This procedure can be repeated as many times as required, allowing the user to see graphically the effect of changes.