OpenCCM is a CFD-based compartment modelling software package. It is primarily intended for convection dominated reactive flows which feature a weak or one-way coupling between the reactive species and the carrier fluid, i.e. the reaction does not substantially influence the fluid flow over the course of the simulation.
Compartments which are only connected to domain inlets/outlets are no longer considered for merging since they don't have anything to be merged into. Such compartments can show up in certain flow reactors, but are very rare outside of structured meshes.
When calculating connections between compartments, we now keep track of if the connection from A -> B was rejected due to being to small to avoid doing the same calculation when it comes time to evaluate B's connections.