| Matrix or Vector | Geometry | Shape Functions | Integration Points |
|---|---|---|---|
| Stiffness and Stress Stiffness Matrices | Quad | Equation 11–134 and Equation 11–135 | 2 x 2 |
| Triangle | Equation 11–112 and Equation 11–113 | 3 | |
| Mass Matrix | Quad | Same as stiffness matrix | 3 x 3 |
| Triangle | 3 | ||
| Pressure and Temperature Load Vector | Same as stiffness matrix, specialized to the edge | 2 | |
| Flow Load Vector | Linear across each edge | 2 | |
| Load Type | Distribution |
|---|---|
| Element Temperature | Same as shape functions across element, constant thru thickness or around circumference |
| Nodal Temperature | Same as element temperature distribution |
| Surface Pressure Load | Linear along each edge |
| Flow and heat flux | Linear along each edge |
Reference: Zienkiewicz(39)
General Element Formulations gives the general element formulations used by this element.