xppm

XPiecewiseParabolic

Fortran name is xppm

__call__(q_in, c, q_mean_advected_through_x_interface)

Determine the mean value per area of q_in to be advected along x-interfaces.

This is done by integrating a piecewise-parabolic subgrid reconstruction of q_in along the x-direction over the segment of gridcell which will be advected.

Multiplying this mean value by the area to be advected through the interface would give the flux of q through that interface.

Parameters:

Name	Type	Description	Default
q_in	in	scalar to be integrated	required
c	in	Courant number (u*dt/dx) in x-direction defined on x-interfaces, indicates the fraction of the adjacent grid cell which will be advected through the interface in one timestep	required
q_mean_advected_through_x_interface	out	defined on x-interfaces. mean value of scalar within the segment of gridcell to be advected through that interface in one timestep, in units of q_in	required

apply_flux(courant, q, fx1, mask)

Parameters:

Name	Type	Description	Default
courant		any value whose sign is the same as the sign of the x-wind on cell corners	required
q		scalar being transported, on x-centers	required
fx1		flux of q in units of q, on x-interfaces	required
mask		fx1 is multiplied by this before being applied	required

compute_al(q, dxa)

Interpolate q at interface.

Inputs

q: transported scalar centered along the x-direction dxa: dx on A-grid (?)

Returns:

Type	Description
	q interpolated to x-interfaces

compute_x_flux(q, courant, dxa, xflux)

Parameters:

Name	Type	Description	Default
q	in		required
courant	in		required
dxa	in		required
xflux	out		required

fx1_fn(courant, br, b0, bl)

Parameters:

Name	Type	Description	Default
courant		courant number, u * dt / dx (unitless)	required
br		???	required
b0		br + bl	required
bl		???	required