Attributes:

1DDI (for 1D fractures) (for 1K or 2K transport models)

2DDI (for 2D fractures) (for 1K or 2K transport models)

Attribute: DISP (element wise) (transport model)

To calculate the mass transfer, the longitudinal dispersivity must be specified for each element (and each fracture).

For the mesh elements (DISP), the transverse-horizontal dispersivity is automatically assumed to be 1/10 of the longitudinal dispersivity. In 3D models, the transverse-vertical dispersivity is assumed to be 1/100 of the longitudinal dispersivity. These preset factors can be changed in the dialog box for the mass transport calculation.

For fractures, the transverse dispersivity is equal to 0.

Schematic representation of the dispersion process