Use the 1D model (an example is given in sample ../1D_ism_init) to obtain
the file init_ism.dat containing density and temperatue profiles for the 
initial condition in this 3D supernova driven turbulence model of the ISM.
The 1D model has identical vertical grid and hydrodynamic run parameters.
Magnetic field and cosmic rays can be added to this 3D model

The averaged SN heating substitutes for the SN driven turbulence and will be
smoothly superceded by the SN explosions as the turbulence evolves.

SN are spatially distributed according to a uniform distribution in the 
horizontal plane and gaussian distribution vertically centred about the 
centre of mass, which fluctuates near to the midlplane. Default SN frequency
rates are milky way estimates and default mass and gravitional acceleration
are taken from the solar vicinity.

Directory:
    ${PENCIL_HOME}/samples/supernova-driven-turbulence/HD3D
SVN Id:
    $Id$
Maintainer:
    Axel Brandenburg <brandenb/nordita[dot]org>
    Fred A. Gent <fred.gent.ncl/gmail[dot]com>
Added:
    18-Jan-2016
Status:
    has been working in this form since 3-Jun-2006
Recommended resolution:
    at least 64x64x128 (dx=dy=dz=4pc) 
Comments:
    This model tests supernova energy injection and the cooling function
References:
    1. Brandenburg, A., Korpi, M. J., & Mee, A. J.: 2007, ``Thermal
       instability in shearing and periodic turbulence,''
       Astrophys. J. 654, 945-954
    2. Korpi, M. J., Brandenburg, A., Shukurov, A., Tuominen, I.,
       & Nordlund, Å.: 1999, ``A supernova regulated interstellar
       medium: simulations of the turbulent multiphase medium,''
       Astrophys. J. Lett. 514, L99-L102
    3. Gent, F.A., Shukurov, A., Fletcher, A., Sarson, G.R.S., &
       Mantere, M.J.: ``Supernova Driven Turbulence. I. The Multiphase
       Structure'',
       MNRAS, 432, 1396-1423 
    4. Gent, F.A., Shukurov, A., Sarson, G.R.S., Fletcher, A., &
       Mantere, M.J.: ``Supernova Driven Turbulence. II. The Mean
       Magnetic Field'',
       MNRAS, 430, L40-L44