  Piernik is a multi-fluid grid magnetohydrodynamic (MHD) code based on the
Relaxing Total Variation Diminishing (RTVD) conservative scheme. The original
code has been extended by addition of dust described within the particle
approximation. The dust is now described as a system of interacting particles.
The particles can interact with gas, which is described as a fluid. The
comparison between the test problem results and the results coming from fluid
simulations made with Piernik code shows the most important differences between
fluid and particle approximations used to describe dynamical evolution of dust
under astrophysical conditions.
