FEM MeshNetgenFromShape

Constant vacuum permittivity

FEM mesh from shape by Gmsh

FEM

Description

For a finite element analysis, the geometry needs to be discretized into a FEM Mesh. This command uses Netgen (which needs to be installed on the system) to generate the mesh. Netgen meshes are not supported by Elmer.

Depending on your operating system and installation package, Netgen might be bundled with FreeCAD or not. For further information see FEM Install.

Usage

1. Select the shape you want to analyze. For a volume, this needs to be solid or compsolid. A compsolid is necessary if your part is made from multiple materials (a compsolid can be created with the Part BooleanFragments command).
2. Activate the tool in one of the following ways:
   • Press the FEM mesh from shape by Netgen button.
   • Select the Mesh → FEM mesh from shape by Netgen option from the menu.
3. Optionally, set the max/min element size (the default setting usually creates meshes that are too coarse) and element order (using the Second Order checkbox).
4. Optionally, change the Fineness to one of the predefined choices or choose UserDefined and manually edit the parameters.
5. Click the Apply button to generate the mesh. introduced in 1.0: Optionally, use the Cancel button to abort meshing if using the new Netgen implementation.
6. Click the OK button to generate the mesh and close the dialogue. You can also click the Cancel button to cancel the changes or creation of the mesh object.

Properties

• DataMax. Size: Maximum size of the element in mm.
• DataMin. Size: introduced in 1.0: Minimum size of the element in mm.
• DataSecond order: Second order elements contain more nodes per element. Usually, it is enough to use rougher mesh to obtain same solution precision as with the first order elements,
  • true (default); second order elements,
  • false; first order elements.
• DataFineness: Offers predefined levels of mesh density.
• DataGrowth Rate: Defines how much adjacent elements can differ in size.
• DataNb. Segs per Edge: Defines the minimum number of mesh segments per edge.
• DataNb. Segs per Radius: Defines the minimum number of mesh segments per radius.
• DataOptimize:
  • true (default): applies optimization algorithm to improve mesh quality
  • false

Constant vacuum permittivity

FEM mesh from shape by Gmsh

FEM

FEM

• FEM Analysis

• Materials: Solid, Fluid, Nonlinear mechanical, Reinforced (concrete); Material editor

• Element geometry: Beam (1D), Beam rotation (1D), Shell (2D), Fluid flow (1D)

---

Constraints

• Electromagnetic: Electrostatic potential, Current density, Magnetization

• Fluid: Initial flow velocity, Initial pressure, Flow velocity

• Geometrical: Plane rotation, Section print, Transform

• Mechanical: Fixed, Displacement, Contact, Tie, Spring, Force, Pressure, Centrif, Self weight

• Thermal: Initial temperature, Heat flux, Temperature, Body heat source

• Overwrite Constants: Constant vacuum permittivity

---

• Mesh: Mesh Netgen, Mesh GMSH, Mesh boundary layer, Mesh region, Mesh group, Nodes set, Mesh to mesh

• Solve: CalculiX Standard, Elmer, Mystran, Z88; Equations: Deformation, Elasticity, Electrostatic, Electricforce, Magnetodynamic, Magnetodynamic 2D, Flow, Flux, Heat; Solver: Solver control, Solver run

• Results: Purge, Show; Postprocessing: Apply changes, Pipeline from result, Warp filter, Scalar clip filter, Function cut filter, Region clip filter, Contours filter, Line clip filter, Stress linearization plot, Data at point clip filter, Filter function plane, Filter function sphere, Filter function cylinder, Filter function box

• Utilities: Clipping plane, Remove clipping planes, Open FEM examples; Mesh clear, Mesh display 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