RAMSES was developed in Saclay to study large scale structure and galaxy formation. It is now a rather flexible package to be used for general purpose simulations in self-gravitating fluid dynamics.
It is written in Fortran 90 with extensive use of the MPI library. It is a free software for non-commercial use only.
This code is a grid-based hydro solver with adaptive mesh refinement. As opposed to patch-based AMR, cells are refined on a cell by cell basis: is therefore called a tree-based AMR.
A very simple interface based on Fortran namelist can be used to specify runtime parameters.
A few routines can be modified to set more complex initial or boundary conditions.
Examples of domain decomposition used in
RAMSES to perform parallel computing.