Hydra

Hydra is an adaptive particle-particle, particle-mesh plus smoothed particle hydrodynamics code.

The latest version (Hydra 4.2) is available as a gzipped tar file. This file also contains an installation file that describes how to compile, test and run the code, additional documentation, both a cosmological initial conditions generator and a skeleton isolated boundary conditions generator, two simple installation tests, several utilities, and a disclaimer.

New in Hydra4 (complete listing):

New, space-saving data format
New units for non-expanding simulations
New program structure resulting in faster execution
New version of SPH with Monaghan-like viscosity
New option to force SPH particle to find exactly nsph neighbours
New correction term for varying smoothing lengths
New option to use entropy as state variable
New option to allow data storage in opposite endianness
New option to save accelerations in backup files
New option to read transfer functions from CMBFAST output
New option to implement steady-state photoionization
New logging options

If you are going to use Hydra then please register by e-mailing Hugh Couchman so that we can send you code updates. We may have already patched that annoying bug !!!