@@ -30,14 +30,24 @@ When a 3D simulation is done by considering only one disk hemisphere (in case of
is automatically introduced at disk midplane. The vertical boundary condition will be then applied only to the gridcells having $`\phi =`$ Opening.
Possible boundaries are:
1.``open`` valid both for 2D and 3D disc. An open boundary will
1.``open``is a radial boundary condition valid both for 2D and 3D disc. An open boundary will
let the gas flowing out at the innermost and outermost radial
gridcell by copying the density of the first active layer
into the ghost one. The sign of the radial velocity controls the
outflow condition.
2.``reflectingR`` and ``reflectingZ`` (3D case only) are commonly used boundaries.
All the quantities are copied from the active cell
2.``reflectingZ`` for the 3D case only, is a mandatory choice for the 3D case unless the user set his own vertical boundary condition.
All the quantities are copied from the first active layer into the
ghost one except the component of the velocity normal to the layer
that is reflected (copied changing the sign).
3.``reflectingR`` is a radial boundary condition (2D and 3D simulations). As for the vertical condition ``reflectingZ`` all the hydro dynamical quantities are copied from the first active layer into the ghost one a part the radial component of the velocity which is reflected.
3.`` evanescent `` is probably the most used radial boundary condition. The aim is to damp waves that propagates and reflect at the ghost cell creating annoying reflections phenomena in the whole
disk. The damping function is described in : de Val-Borro M., Edgar R.~G., Artymowicz P., Ciecielag P., Cresswell P., D'Angelo G., Delgado-Donate E.~J., et al., 2006, MNRAS, 370, 529.
This condition is active in a specific radial domain (whose size in
the code is set according to Benitez-Llambay P., Ramos X.~S., Beauge C., Masset F.~S., 2016, ApJ, 826.
This condition requires to provide azimuthally averaged values for
the whole set of hydrodnamical quantities in the damping domain.
In general such values are provided by initial conditions. The idea
is that the disc is unperturbed at the innermost and outermost radial layers. The damping domain ensures convergence to unperturbed conditions.
