Particle propagator

PushEtaPC

Advances var.

What it solves

For each marker

p

, solves

\frac{d x _{p} ( t )}{d t} = v_{p} + U (x_{p} (t)),

for constant $v_{p}$ and $U$ in logical space given by $x = F (η)$ :

\frac{d η _{p} ( t )}{d t} = D F^{- 1} (η_{p} (t)) v_{p} + vec (U^),

where

vec (U^^{1}) = G^{- 1} U^^{1}, vec (U^^{2}) = \frac{U ^ ^{2}}{g}, vec (U^) = U^.

Available algorithms:

rk4 (4th order, default) forward_euler (1st order) heun2 (2nd order) rk2 (2nd order) * heun3 (3rd order)

The variables this step updates over a time step dt, and the discrete spaces each one accepts.

Name	Kind	Accepted spaces
`var`	PICVariable or SPHVariable	—

Set these on the propagator in a parameter file, for example PushEtaPC.Options(butcher=...).

Option	Default	Choices	Description
`butcher`	`None`	ButcherTableau	Butcher tableau used for explicit Runge-Kutta marker pushing. If `None`, defaults to `ButcherTableau()`.
`use_perp_model`	`True`	bool	Flag forwarded to the particle kernel to select the perpendicular model formulation.
`u_space`	`Hdiv`	`HcurlHdivH1vec`	FEEC space used to interpret `u_tilde` in the pusher kernel.

Each model splits its time step into a sequence of propagators. This one appears in 1 model, at the position shown.