In recent years we have developed a series of codes able to compute complex wind-dynamics and to derive synthetic spectra from the computed density, velocity, and temperature structure. This code package is freely available for all people interested in using it in their research.

AMRCART is a highly flexible code to compute magnetic and radiative flows in one up to three space dimensions. It makes use of a high-resolution finite volume integrator and has an adaptive algorithm implemented which automatically adjusts the spatial and temporal discretization where a higher resolution is needed. The code is user friendly in the sense that only three subroutines have to be changed to adapt the code for a new problem. Together with the numerical techniques we present a variety of astrophysical applications, from magnetic jets in young stellar objects to colliding wind binaries.

D3NEBEL is a code to compute optically thin NLTE radiative transfer in moving media under nebular conditions. Under such conditions, it is able to compute the temperature and ionization structure of 3D density and velocity distributions into which an ionizing source is embedded. Synthetic, Doppler-shifted line profiles can be computed as well. The computations are performed along a series of independent rays, all emerging from the radiation source. We present applications to colliding wind and accretion models of symbiotic binaries.

Still under development is the code TR3D which is able to compute optically thick NLTE radiative transfer in moving media in 3D. It uses a mean intensity approach and short characteristics. The transfer part is solved using modern iterative techniques. Lines are treated with Sobolev approximation, generalized to 3D. We present the numerical techniques as well as a first application, a toy model of the hot star colliding wind binary gamma Velorum.