Element Type

The user can choose between 4 different finite Element Types in the Mesh Setup dialog:

• 3 noded triangle
• 6 noded triangle
• 4 noded quadrilateral
• 8 noded quadrilateral

3-noded triangle, 4-noded quadrilateral

6-noded triangle, 8-noded quadrilateral

Linear Elements

The 3-noded triangle and 4-noded quadrilateral elements has two nodes per element side (see figure above), which are referred to as linear elements. The shape functions in these elements are linear.

Quadratic Elements

The 6-noded triangle and 8-noded quadrilateral elements has three nodes per element side (see figure above), which are referred to as quadratic elements. An additional midside node exists on each element side, enabling the shape functions to be quadratic. This higher order shape function allows for curved sides approximation.

If you are using quadratic elements, the midside nodes will be displayed on the mesh as small circular dots at the midpoint of each finite element edge. The display of the midside nodes can be turned on or off at any time, in the Display Options dialog.

The user should be aware that using elements with midside nodes will greatly increase the size of the matrices used to solve the problem, and will therefore increase solution time and memory requirements.