GfsAdvectionParams

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GfsAdvectionParams is used to control the parameters of various advection schemes.

The syntax in parameter files is:

GfsAdvectionParams {
  cfl = 0.8
  gradient = gfs_center_van_leer_gradient
  scheme = godunov
  moving_order = 1
  vx = 0 vy = 0 vz = 0
}

where the parameters have been set to their default values and where

cfl
is the CFL number,
gradient
the function used to compute the gradient of advected variables. One of:

none
the gradient is set to zero (i.e. spatially first-order scheme),
gfs_center_gradient
second-order centered estimate (no limiter),
gfs_center_van_leer_gradient
van Leer generalised minmod limiter (θ = 2),
gfs_center_minmod_gradient
minmod limiter,
gfs_center_sweby_gradient
sweby limiter (β = 1.5),
gfs_center_superbee_gradient
superbee limiter.

scheme
either godunov for the default Godunov advection scheme, or none to switch advection off entirely,
moving_order
only relevant for GfsSimulationMoving, either 1 for the default first-order moving boundaries scheme, or 2 for the second-order scheme,
vx, vy, vz
the components of a "sinking velocity" to add when advecting a GfsVariableTracer. It can be functions. When present. it has to be specified ALL the components of the "sinking velocity" (vx and vy in 2D; vx, vy and vz in 3D). In addition, it is advisable that each component goes in separated lines.

Examples

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