FEM Mesh CalculiX

FEM element types in CalculiX

For detailed information on FreeCAD FEM elements see FEM Mesh and FEM Element Types. For CalculiX specific questions you may try the Discourse group or the Discord channel.

Segment element

**Segment element from FreeCAD to CalculiX -- node assignment**
seg2 FreeCAD nodes	seg3 FreeCAD nodes

seg2 (B31) CalculiX nodes	seg3 (B32) CalculiX nodes

FreeCAD → CalculiX, Nodes
N1, N2	N1, N3, N2

Triangle element

**Triangle element from FreeCAD to CalculiX -- node assignment**
tria3 FreeCAD nodes	tria6 FreeCAD nodes

tria3 (S3) CalculiX nodes	tria6 (S6) CalculiX nodes

FreeCAD → CalculiX, Nodes
N1, N2, N3	N1, N2, N3, N4, N5, N6

Quadrangle element

**Quadrangle element from FreeCAD to CalculiX -- node assignment**
quad4 FreeCAD nodes	quad8 FreeCAD nodes

quad4 (S4) CalculiX nodes	quad8 (S8) CalculiX nodes

FreeCAD → CalculiX, Nodes
N1, N2, N3, N4	N1, N2, N3, N4, N5, N6, N7, N8

Tetrahedron element

The following node order is not implemented ! TODO: verify node order (do not forget getccxVolumesByFace()).

**Tetrahedron element from FreeCAD to CalculiX -- node assignment**
tetra4 FreeCAD nodes	tetra10 FreeCAD nodes

tetra4 (C3D4) CalculiX nodes	tetra10 (C3D10) CalculiX nodes

FreeCAD → CalculiX, Nodes
N2, N3, N4, N1	N2, N3, N4, N1, N6, N10, N9, N5, N7, N8

Hexahedron element

**Hexahedron element from FreeCAD to CalculiX -- node assignment**
hexa8 FreeCAD nodes	hexa20 FreeCAD nodes

hexa8 (C3D8) CalculiX nodes	hexa20 (C3D20) CalculiX nodes

FreeCAD → CalculiX, Nodes
N6, N7, N8, N5, N2, N3, N4, N1	N6, N7, N8, N5, N2, N3, N4, N1, N14, N15, N16, N13, N10, N11, N12, N9, N18, N19, N20, N17

Pentahedron element

**Pentahedron element from FreeCAD to CalculiX -- node assignment**
penta6 FreeCAD nodes	penta15 FreeCAD nodes

penta6 (C3D6) CalculiX nodes	penta15 (C3D15) CalculiX nodes

FreeCAD → CalculiX, Nodes
N5, N6, N4, N2, N3, N1	N5, N6, N4, N2, N3, N1, N11, N12, N10, N8, N9, N7, N14, N15, N13

Related

FEM CalculiX page
CalculiX preferences dialog menu in the FEM Workbench preferences menu

FEM

New Analysis

Materials: Solid Material, Fluid Material, Non-Linear Mechanical Material, Reinforced Material (Concrete); Material Editor

Element Geometry: Beam Cross Section, Beam Rotation, Shell Plate Thickness, Fluid Section for 1D Flow

Electromagnetic Boundary Conditions: Electrostatic Potential Boundary Condition, Current Density Boundary Condition, Magnetization Boundary Condition, Electric Charge Density

Fluid Boundary Conditions: Initial Flow Velocity Condition, Initial Pressure Condition, Flow Velocity Boundary Condition

Geometrical Analysis Features: Plane Multi-Point Constraint, Section Print Feature, Local Coordinate System

Mechanical Boundary Conditions and Loads: Fixed Boundary Condition, Rigid Body Constraint, Displacement Boundary Condition, Contact Constraint, Tie Constraint, Spring Boundary Condition, Force Load, Pressure Load, Centrifugal Load, Gravity Load

Thermal Boundary Conditions and Loads: Initial Temperature, Heat Flux Load, Temperature Boundary Condition, Body Heat Source

Overwrite Constants: Constant Vacuum Permittivity

Mesh: Mesh From Shape by Netgen, Mesh From Shape by Gmsh, Mesh Boundary Layer, Mesh Refinement, Mesh Group, Erase Elements, FEM Mesh to Mesh

Solve: Solver CalculiX, Solver Elmer, Solver Mystran, Solver Z88; Mechanical Equations: Elasticity Equation, Deformation Equation; Electromagnetic Equations: Electrostatic Equation, Electricforce Equation, Magnetodynamic Equation, Magnetodynamic 2D Equation, Static Current Equation; Flow Equation, Flux Equation, Heat Equation, Solver Job Control, Run Solver

Results: Purge Results, Show Result, Apply Changes to Pipeline, Post Pipeline From Result, Pipeline Branch, Warp Filter, Scalar Clip Filter, Function Cut Filter, Region Clip Filter, Contours Filter, Glyph Filter, Line Clip Filter, Stress Linearization Plot, Data at Point Clip Filter, Calculator Filter; Filter Functions: Plane, Sphere, Cylinder, Box; Data Visualizations: Create Lineplot, Create Histogram, Create Table

Utilities: Clipping Plane on Face, Remove All Clipping Planes, FEM Examples; Clear FEM Mesh, Display Mesh Info

Additional: Preferences; FEM Install, FEM Mesh, FEM Solver, FEM CalculiX, FEM Concrete; FEM Element Types

User documentation

Getting started
Installation: Download, Windows, Linux, Mac, Additional components, Docker, AppImage, Ubuntu Snap
Basics: About FreeCAD, Interface, Mouse navigation, Selection methods, Object name, Preferences, Workbenches, Document structure, Properties, Help FreeCAD, Donate

Help: Tutorials, Video tutorials
Workbenches: Std Base, Assembly, BIM, CAM, Draft, FEM, Inspection, Material, Mesh, OpenSCAD, Part, PartDesign, Points, Reverse Engineering, Robot, Sketcher, Spreadsheet, Surface, TechDraw, Test Framework

Addons: Addon Manager, External workbenches, Scripting and macros

Hubs: User hub, Power users hub, Developer hub