ABSTRACT
Dmox denoting the dimensions of the region where the relaxation effects are important and m the average mass.
Boundary and initial conditions must be again chosen.
If one of the most delicate points of the fluid-dynamical method is to cut the equations system, another is to replace partial derivatives by finite differences. The reader interested in numerical treatments of fluid-dynamical methods will refer for instance to papers of R.B. Larson (and others) in Monthly Notices Roy. Astron. Soc., Astronomy and Astrophysics, Astrophys. Space Sci., ...
