Finite Element Analysis (FEA) provides a reliable numerical technique for analyzing engineering designs. The process starts with the creation of a geometric model. Then, the program subdivides the model into small pieces of simple shapes called elements connected at common points called nodes. The process of subdividing the model into small pieces is called meshing. Finite element analysis programs look at the model as a network of interconnected elements.
Meshing is a crucial step in design analysis. The software automatically creates a mixed mesh of solid, shell and beam elements. The solid mesh is appropriate for bulky or complex 3D models. Shell elements are suitable for thin parts (like sheet metals). Beam elements are suitable for structural members.
The accuracy of the solution depends on the quality of the mesh. In general, the finer the mesh the better the accuracy. The generated mesh depends on the following factors:
- Created geometry
- Active Mesh options
- Mesh control
- Contact conditions
- Global element size and mesh tolerance. The software suggests a global element size and tolerance. The global element size refers to the average length of an element edge. The number of elements increases rapidly by using a smaller global element size.
Mesh Type Based on Geometric Features
The program automatically assigns the appropriate mesh type to bodies based on their geometry features.
| Solid Mesh |
All solid models mesh with solid (tetrahedral) elements. |
| Shell Mesh |
Surface geometries and sheet metals with uniform thickness mesh with triangular shell elements. Sheet metals defined in a drop test study mesh with solid elements. |
| Beam Mesh |
Structural members and weldments mesh with beam elements. You can treat an extrusion (meshes with solid elements by default) as a beam by right-clicking on the solid icon and selecting Treat as Beam. |
| Mixed Mesh |
When different geometries are present in the same model, a mixed mesh is generated. |
Design studies and fatigue studies use the mesh of the associated studies. Drop test studies use solid mesh only. Pressure vessel studies combine results and do not require a mesh.
Adaptive Methods for Static Studies
Adaptive methods help you obtain an accurate solution for static studies. There are two types of adaptive methods: h-adaptive and p-adaptive method. The concept of the h-method is to use smaller elements in regions with high relative errors. The p-adaptive method increases the polynomial order of elements with high relative errors.