| ... | ... | @@ -279,18 +279,18 @@ possible values or a numeric range. |
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magnetic field component is obtained by a divergence-free
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extrapolation.
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- `O`: outflow -- fluid is allowed to flow outwards through
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- `O`: outflow - fluid is allowed to flow outwards through
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the corresponding domain boundary but not to flow inwards.
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For the perpendicular velocity component this means
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$u_o=\mp\operatorname{sgn}u_i\cdot u_i$ where the
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'+'('-')-sign is valid for a lower (upper) domain boundary.
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Other variables are set likewise to inflow I.
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- `M`: mirror symmetry -- reflecting conditions, $u_o=-u_i$,
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- `M`: mirror symmetry - reflecting conditions, $u_o=-u_i$,
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for the perpendicular components of velocity and magnetic
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field. Zero derivative for the other variables.
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- `A`: anti-mirror symmetry -- same as M for non-magnetic
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- `A`: anti-mirror symmetry - same as M for non-magnetic
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variables. The magnetic field is forced to have dipole
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parity with respect to the domain boundary. This means
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$u_o=-u_i$ for the parallel magnetic field components and
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| ... | ... | @@ -299,26 +299,26 @@ possible values or a numeric range. |
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- `R`: reflection-on-axis (only of relevance in cylindrical
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geometry at the $y$-lower boundary at $R=0$ or in
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spherical geometry at the $y$-lower/upper boundaries at
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$\theta =0,\pi$) -- reflecting conditions at the geometric
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$\theta =0,\pi$) - reflecting conditions at the geometric
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axis. Same as M except for the azimutal magnetic field
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component for which $u_o=-u_i$.
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- `C`: reflection-at-center (only of relevance in spherical
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geometry at the $x$-lower boundary at $r=0$) -- reflecting
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geometry at the $x$-lower boundary at $r=0$) - reflecting
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conditions at the coordinate center. Same as M except for
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the non-radial magnetic field components for which
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$u_o=-u_i$.
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- `P`: periodicity -- periodic conditions for all variables.
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- `P`: periodicity - periodic conditions for all variables.
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- `D`: default -- zero derivative in the non-magnetic
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- `D`: default - zero derivative in the non-magnetic
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variables and perpendicular-to-boundary condition
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(pseudo-vacuum condition) for the magnetic field.
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- `F`: free boundary (only of relevance in cylindrical
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geometry at the $y$-lower boundary at $R=0$ or in
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spherical geometry at the $y$-lower/upper boundaries at
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$\theta =0,\pi$ and $x$-lower boundary at $r=0$) --
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$\theta =0,\pi$ and $x$-lower boundary at $r=0$) -
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'natural' boundary condition at the geometric axis. Boundary
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values are not set explictely but are implicitly given by
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$\pi$-shifted values. Note that when a `F`-type boundary
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