Solver configuration

Note

ember.config.SolverConfig (documented on this page) belonged to the legacy ember.run solver loop and has been removed. The current solver’s configuration is ember.scree.ScreeConfig.

The Navier–Stokes algorithm page describes how each parameter below influenced the stages of the legacy time-stepping loop.

class ember.scree.ScreeConfig(n_step, n_step_log=10, n_step_source=1, n_step_avg=1, cfl=0.4, sf4=0.008, sf2=0.002, dampin=None, inviscid=False, fac_visc=1.0, sf_resid=0.0, gain_filt=0.0, delta_filt=1.0, n_stage=0, n_levels=0, fac_mgrid=0.2)

Configuration for the scree explicit time march.

n_step: int

n_step_log: int = 10

Number of steps between convergence log messages.

n_step_source: int = 1

Number of steps between source term refreshes.

n_step_avg: int = 1

Number of steps to average over.

cfl: float = 0.4

Constant CFL number for the scree march

sf4: float = 0.008

Fourth-order smoothing factor.

sf2: float = 0.002

Second-order smoothing factor.

dampin: float | None = None

Negative-feedback damping factor on integrated residual.

inviscid: bool = False

Skip viscous terms in the sources evaluation.

fac_visc: float = 1.0

Multiplier on the turbulent-diffusion timestep radius; >1 tightens the viscous limit to recover the inviscid stable CFL.

sf_resid: float = 0.0

Implicit residual smoothing factor

gain_filt: float = 0.0

Selective frequency damping gain.

delta_filt: float = 1.0

Selective frequency damping filter width (higher is smoother).

n_stage: int = 0

Number of time integration stages per step. 0 for scree, >=1 for RK.

n_levels: int = 0

Number of coarse multigrid levels; 0 disables multigrid.

fac_mgrid: float = 0.2

Scaling factor on multigrid corrections.