About Finite Element Model Representations

Finite element model representations are alternative representations of geometries that contain meshes. A finite element model representation can also be called a FE Model representation or FEM representation.

Finite element model representations are 1D, or 2D simplified and abstract representations of design models.

As with other representations, the FEM representation is attached to a product, and a product can contain several FEM representations. However, only one FEM representation can be associated with each simulation.

The process of splitting a complex part into elements is called meshing; the resulting collection of finite element meshes is a finite element model. For more information, see About Meshes.

You must define a FEM representation before simulating a mechanical structure in a Physics Simulation app.

For an assembly, you can define a FEM representation using a mesh of the assembly.

The first method is the default; it creates a FEM representation that includes one mesh containing all the parts in the assembly. This method is appropriate for assemblies where uniform mesh controls are suitable for all components and where there are few instances of the same parts. The second method provides you with controls to link existing FEM representations or to create new ones for each component in the assembly. Creating an assembly of meshes allows you to retain customized meshes for individual components and to avoid extra computational expense when multiple instances of the same parts are used in the assembly.

You must have a FEM representation before you can perform any other model action. If you enter a model creation app without first creating or selecting a FEM representation for the model, the procedure to create a new FEM representation is started automatically. If you enter a model creation app by switching from a scenario creation app, you are required to select an existing FEM representation or to create one before switching.

FEM Representation Categories

A finite element model (FEM) representation contains predefined categories that help you to classify the objects stored in the finite element model.

A FEM representation contains:

  • Meshes made of finite elements
  • Structural properties applied to the finite elements
  • Groups of elements
  • Abstractions

In the tree:

  • Meshes are stored under the Nodes and Elements category.
  • Structural properties are stored under the Properties category.
  • Groups of elements can be stored under the Groups category or directly under a mesh.
  • Abstractions (for example, rigid bodies and fluid cavities) are stored under the Abstractions category.