Changes
Page history
version 4.2
authored
Oct 30, 2025
by
Udo Ziegler
Show whitespace changes
Inline
Side-by-side
3-NIRVANA-user-guide/3.1-Code-basics.md
View page @
6042be78
...
...
@@ -405,7 +405,8 @@ individually selected by the user. The standard implementation covers
the following criteria:
-
derivatives-based (most important in practice):
!
[
amr_deriv
](
uploads/25c608e1a335aca4242b34afb9e4ffeb/amr_deriv.png
)
{width=80%}
!
[
amr_deriv
](
uploads/25c608e1a335aca4242b34afb9e4ffeb/amr_deriv.png
)
{width=100%}
The criterion is applied to physical variables $U$
($=\{\varrho,\mathbf{m},e,\mathbf{B},C_\mathrm{c}\}$). Undivided
first ($\delta U$) and second ($\delta^2U$) differences are computed along
...
...
@@ -430,7 +431,7 @@ the following criteria:
side) to decide whether a child block is to be created.
-
Jeans-length-based (important in simulations involving selfgravity):
!
[
amr_Jeans
](
uploads/57691ce992d4c86be15b6e7b5637166b/amr_Jeans.png
)
{width=
8
0%}
!
[
amr_Jeans
](
uploads/57691ce992d4c86be15b6e7b5637166b/amr_Jeans.png
)
{width=
10
0%}
where the first factor is the local Jeans
length with $c_s$ the sound speed and $G$ the gravitational
...
...
@@ -441,7 +442,7 @@ the following criteria:
-
Field-length-based (potentially relevant for simulations involving a
heatloss source but rarely used in practice):
!
[
amr_Field
](
uploads/de458510a631f1c2c18766c32f92eff1/amr_Field.png
)
{width=
8
0%}
!
[
amr_Field
](
uploads/de458510a631f1c2c18766c32f92eff1/amr_Field.png
)
{width=
10
0%}
where the first factor is the Field length with
$L(\varrho, T)$ the density- and temperature-dependent heatloss
...
...
...
...