AMUN is a parallel code to perform numerical simulations in fluid approximation on uniform or non-uniform (adaptive) meshes. The goal in developing this code is to create a solid framework for simulations with support for number of numerical methods which can be selected in an easy way through the parameter file. The following features are already implemented:

• hydrodynamic and magnetohydrodynamic set of equations (HD and MHD),
• both classical and special relativity cases for the above equations,
• Cartesian coordinate system,
• uniform and adaptive mesh generation and update,
• 2nd to 4th order time integration using Strong Stability Preserving Runge-Kutta methods,
• 2nd order TVD interpolation with number of limiters and higher order reconstructions,
• Riemann solvers of Roe- and HLL-types (HLL, HLLC, and HLLD),
• periodic and open boundary conditions,
• viscous and resistive source terms,
• data stored in the HDF5 format,
• MPI parallelization,
• completely written in Fortran 2003.

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

Developers

• Grzegorz Kowal grzegorz@amuncode.org

Requirements

• Fortran 2003 compiler (tested compilers include GNU Fortran version 4.5 or newer, Intel Fortran compiler version 9.0 or newer)
• HDF5 libraries version 1.8 or newer.
• OpenMPI version 1.8 or newer for parallel runs.

Environment Variables

If the HDF5 libraries are not installed in the default location, i.e. in the system directory /usr, make sure that the environment variable HDF5DIR is set in your ~/.bashrc (or ~/.cshrc) and pointing to the location where the HDF5 libraries have been installed.

Compilation

1. Clone the AMUN source code: git clone https://bitbucket.org/amunteam/amun-code.git, or unpack the archive downloaded from page Downloads.
2. Go to directory build/hosts/ and copy file default to a new file named exactly as your host name (name returned by command hostname).
3. Customize your compiler and compilation options in your new host file.
4. Go up to directory build/ and copy file make.default to make.config.
5. Customize compilation time options in make.config.
6. Compile sources by typing make in directory build/. The executable file amun.x should be created there.

Usage

In order to run some test problems you can simply copy corresponding parameter from directory problems/ to the location when you wish to run your test. Copy the executable file amun.x compiled earlier to the same directory. If you provide option -i <parameter_file>, the code will know that the parameters have to be read from file <parameter_file>. If you don't provide this option, the code will assume that the parameters are stored in file params.in in the same director.

In order to run serial version, type in your terminal: amun.x -i params.in.

In order to run the parallel version (after compiling the code with MPI version), type in your terminal: mpirun -n N ./amun.x -i params.in, where N is the number of processors.