Use the model after Millington (1961) for the effective diffusivity.
#include <dumux/porousmediumflow/richardsextended/model.hh>
| Public Types | |
| using | type = DiffusivityMillingtonQuirk<GetPropType<TypeTag, Properties::Scalar>> | 
| using Dumux::Properties::EffectiveDiffusivityModel< TypeTag, TTag::ExtendedRichards >::type = DiffusivityMillingtonQuirk<GetPropType<TypeTag, Properties::Scalar>> |