# Rigid-Field Hydrodynamics model

As the next step beyond the RRM model, the Rigidy Field Hydrodynamics (RFHD) model introduced by Townsend et al. (2007) simulates the flow along each rigid field line using a 1-dimensional non-Cartesian hydrodynamical code. (The non-Cartesian bit takes care of the natural area divergence of magnetic flux tubes). By conducting simulations for many separate field lines, and then stitching them together, a complete 3-dimensional model can be built up at a fraction of the computational cost cost of an equivalent MHD simulation.

## Implementation

My current RFHD code is based on the VH-1 code developed by John Blondin and co-workers. Modifications to the code include the implementation of the non-Cartesian geometry; the inclusion of radiative driving using the standard CAK formalism; the addition of radiative cooling using my exact integration scheme (Townsend 2009), and most recently the inclusion of thermal conduction.

## Selected Bibliography

- Townsend, Owocki & ud-Doula (2007) — the original RFHD paper