15.  Define element types and options.

In any analysis, you need to select from a library of element types and define the appropriate ones for your analysis.

For this analysis, we’ll use only one element type, PLANE82, which is a 2-D, quadratic, structural, higher-order element. The choice of a higher-order element here allows us to have a coarser mesh than with lower-order elements while still maintaining solution accuracy. Also, some triangle shaped elements will be generated in the mesh that would otherwise be inaccurate if lower-order elements (PLANE42) were used. We’ll need to specify plane stress with thickness as an option for PLANE82. (The thickness will be defined as a real constant in the next step.)

1. Main Menu:  Preprocessor
        Element Type
             Add/Edit/Delete
2. Add an element type  -»
3. Structural solid family of elements  -»
4. Choose the 8-noded quad (PLANE82)  -»
5. OK to apply the element type and close the dialog box  -»
6. Options for PLANE82 are to be defined  -»
7. Choose plane stress with thickness option for element behavior  -»
8. OK to specify options and close the options dialog box  -»
9. Close the element type dialog box  -»