Overview > Finite Element Anaylsis and VisualFEA > Creating a finite element model using VisualFEA

 

Creating a finite element model using VisualFEA

A finite element model designates an aggregate of data as a subject of finite element analysis, and typically consists of the following data items:   

  node data : node identification, nodal coordinates
  element data : element-node relations, connectivities
  attributes : element properties, integration rule
  boundary conditions : boundary constraints, initial states
  external effects : applied forces, temperature

The above items are in fact the input data items used at the processing stage. There are other data items which are necessary only for pre- and postprocessing purposes in VisualFEA.

A finite element model is completed by creating nodes and elements and assigning attributes, boundary conditions and external effects.

> Node and element data

The geometry of a finite element model is defined by nodes and elements in VisualFEA. An element has a specified number of nodes. The node-element relations are established as a part of a finite element mesh. Some nodes are created by dividing curves used as a seed for mesh generations, and the others are created by mesh generation.

There are line elements for frame analysis, surface elements for plane or shell analysis, and volume elements for 3-dimensional solid analysis. Line elements are created by dividing a curve, or by direct line drawing. Surface elements are created by surface mesh generation. A surface mesh is generated using boundary curves or seed curves. Volume elements are created by volume mesh generation which are usually derived from surface mesh.

A mesh has a hierarchical structure in VisualFEA. The hierarchical construction of a mesh is schematically represented in the following figure.

> Other data assignment

A finite element model is geometrically embodied by nodes and elements. But it is not complete unless proper data are assigned to nodes and elements. The finite element model becomes ready for analysis, only when the following data items at least are assigned, depending on the analysis subject.   

  structural problem: element properties, boundary conditions( initial displacements), load conditions.
  heat transfer analysis: element properties, heat boundary condition.

< Hierarchical construction of line, surface and volume elements >