The PorousFlowDictator

The PorousFlowDictator is a UserObject that holds information about the nonlinear variables used in the PorousFlow module, as well as the number of fluid phases and fluid components in each simulation.

Other PorousFlow objects, such as Kernels or Materials query the PorousFlowDictator to make sure that only valid fluid components or phases are used.

The PorousFlowDictator also resolves the FE type of the variables that nodal Materials read at the nodes, and produces an error if they do not all share one. See which nodes are evaluated for why they must.