FEM CalculiX/it

Questa pagina raccoglie tutte le informazioni relative al solutore utilizzato dal Modulo FEM di FreeCAD. Viene anche descritta l'interfaccia tra il risolutore e FreeCAD in pre e post elaborazione. Al momento (Mid 2015 e FreeCAD 0.16dev) l'unico solver supportato dal modulo FEM è [CalculiX].

CalculiX

Depending on the operating system you are working with you need to install CalculiX first. Check out [FEM Install].

Interface

Interaction between FEM Module and CalculiX is done by text files. The FEM Module writes a CalculiX input file, starts CalculiX, logs the output of CalculiX and read the output files of CalculiX if they are available. The FEM_Calculation tool manages the whole process. User interaction in the process is possible.

Preprocessing interface

CalculiX uses abaqus input file format. The input file could be edited before the solver is started. The units used in the CalculiX input file are independet from the units used in FreeCAD. They will be mm and N. (ToDo: check this. What happens with the mesh if inch is used in FreeCAD. Density was introduced. With this we have kg and s and no longer N?! how about this !?!)

The FEM Module - CalculiX interface supports the following objects:

FEM Elements

• Tet4 and Tet10 --> FEM_Mesh#Tetrahedron_element Tetrahedron
• S3 and S6 as well as B31 and B32 are in development

Analysis

• linear static analysis

Materials

• one linear elastic isotropic (uniformity in all directions) material
• multiple material is in development

Postprocessing interface

read resulting stress (Von Mises) and all displacement