fluidsim.solvers.sphere.ns2d.solver

NS2D equations over a sphere (fluidsim.solvers.sphere.ns2d)

class fluidsim.solvers.sphere.ns2d.solver.InfoSolverSphereNS2D(only_root=False, **kargs)

Bases: InfoSolverSphericalHarmo

Contain the information on a base pseudo-spectral solver.

_init_root()

Init. self by writting the information on the solver.

class fluidsim.solvers.sphere.ns2d.solver.SimulSphereNS2D(params)

Bases: SimulSphericalHarmo

Pseudo-spectral base solver.

InfoSolver

alias of InfoSolverSphereNS2D

tendencies_nonlin(state_spect=None, old=None)

Compute the nonlinear tendencies.

Parameters:

state_spectfluidsim.base.setofvariables.SetOfVariables

optional

Array containing the state, i.e. the vorticity, in Fourier space. If state_spect, the variables vorticity and the velocity are computed from it, otherwise, they are taken from the global state of the simulation, self.state.

These two possibilities are used during the Runge-Kutta time-stepping.

Returns:

tendencies_shfluidsim.base.setofvariables.SetOfVariables

An array containing the tendencies for the vorticity.

Notes

The 2D Navier-Stokes equation can be written

\[\partial_t \hat\zeta = \hat N(\zeta) - \sigma(k) \hat \zeta,\]

This function compute the nonlinear term (“tendencies”) \(N(\zeta) = - \mathbf{u}\cdot \mathbf{\nabla} \zeta\).

Classes

InfoSolverSphereNS2D([only_root])	Contain the information on a base pseudo-spectral solver.
Simul	alias of SimulSphereNS2D
SimulSphereNS2D(params)	Pseudo-spectral base solver.