| Matrix or Vector | Geometry | Shape Functions | Integration Points |
|---|---|---|---|
| Diffusivity Matrix and Diffusing Substance Generation Load Vector | Brick | Equation 11–238 | 14 |
| Wedge | Equation 11–213 | 3 x 3 | |
| Pyramid | Equation 11–197 | 2 x 2 x 2 | |
| Tet | Equation 11–190 | 4 | |
| Damping Matrix | Same as diffusivity matrix. If KEYOPT(1) = 1, the damping matrix is diagonalized as described in Lumped Matrices. | ||
| Diffusion Flux Load Vector | Quad | Equation 11–93 | 3 x 3 |
| Triangle | Equation 11–65 | 6 | |
Diffusion in the Mechanical APDL Theory Reference describes the derivation of diffusion element matrices and load vectors as well as diffusion flux evaluation.