AdvectionBase

class fridom.framework.modules.advection.AdvectionBase

Bases: Module

Base class for advection schemes.

Description

This class implements the base interface for 1D, 2D, and 3D advection schemes. For that, it is assumed that the velocity field is stored in the state vector as the components u, v, and w. Child classes must implement the advection method to calculate the advection term:

\[\mathcal{A}(\boldsymbol{v}, q) = -\boldsymbol{v} \cdot \nabla q\]

where \(q\) is the quantity to be advected and \(\boldsymbol{v}\) is the velocity field, which is the sum of the velocity field in the state vector and the background velocity field, stored in the background attribute. This update routine of this module adds the advection term multiplied by the nonlinear scaling factor to the tendency term of all fields that are not flagged with NO_ADV:

\[\partial_t q \leftarrow \partial_t q + \rho \mathcal{A}(\boldsymbol{v}, q)\]

where \(\rho\) is the nonlinear scaling factor.

__init__() → None

Methods

__init__()
advect_state(z, dz)	Advect the state vector.
advection(velocity, quantity)	Advect a quantity using the given velocity field.
disable()	Disable the module.
enable()	Enable the module.
is_enabled()	Whether the module is enabled or not.
reset()	Stop and start the module.
setup(mset[, setup_mode])	Set the module up.
start()	Start the module.
stop()	Stop the module.
update(mz)	Update the model state.

Attributes

background	The background state.
diff_module	The differentiation module to be used by this module.
disable_nonlinear	Whether to disable advection by the state vector itself.
grid	The grid of the model settings.
info	Return a dictionary with information about the time stepper.
interp_module	The interpolation module to be used by this module.
is_setup	Whether the module is set up.
mset	The model settings.
name
required_halo	The required halo points for this module.
scaling	A scaling factor for the nonlinear terms (default: 1.0).

name = 'Advection Base'

abstract advection(velocity: VectorField, quantity: ScalarField) → ScalarField

Advect a quantity using the given velocity field.

advect_state(z: VectorField, dz: VectorField) → VectorField

Advect the state vector.

update(mz: ModelState) → ModelState

Update the model state.

Description

This method is called by the model at each time step. Child classes should overwrite this method to update the module. Make sure to decorate the method with the @module_method decorator.

Parameters

mzfr.ModelState

The model state at the current time step.

Returns

fr.ModelState

The updated model state.

property disable_nonlinear: bool

Whether to disable advection by the state vector itself.

Advection by the background state is still enabled.

property scaling: float

A scaling factor for the nonlinear terms (default: 1.0).

Description

Some modules require to scale the nonlinear terms, as for example the optimal balance projection (fridom.framework.projection.OptimalBalance). This parameter provides an interface to set this scaling factor.

property background: VectorField

The background state.