We have one main routine to generate *.pvd files from existing vtk files. This is useful if no *.pvd file was generated during the simulation, or if you want to generate a *.pvd file from a collection of vtk files that were generated in different simulations. The *.pvd file can be used to animate temporal data in paraview. You can either provide a Vector of the files or the specific time step or the function reads the directory and assigns a pseudo time step to the *.pvd file.
GeophysicalModelGenerator.make_paraview_collection