Freestream

Freestream#

class Freestream[source]#

Bases: BoundaryBaseWithTurbulenceQuantities

Freestream defines the freestream boundary condition.

Example

  • Define freestream boundary condition with velocity expression and boundaries from the volume mesh:

    >>> fl.Freestream(
...     surfaces=[volume_mesh["blk-1/freestream-part1"],
...               volume_mesh["blk-1/freestream-part2"]],
...     velocity=["min(0.2, 0.2 + 0.2*y/0.5)", "0", "0.1*y/0.5"]
... )

  • Define freestream velocity with a compile-time vector expression:

    >>> spanwise_direction = fl.UserVariable(
...     name="spanwise_direction", value=[0, 1, 0]
... )
>>> velocity_basis = fl.UserVariable(
...     name="velocity_basis", value=[0, 0, 12] * u.m / u.s
... )
>>> fl.Freestream(
...     surfaces=[volume_mesh["blk-1/freestream-part1"]],
...     velocity=fl.math.cross(spanwise_direction, velocity_basis)
... )

  • Define freestream boundary condition with turbulence quantities and automated farfield:

    >>> auto_farfield = fl.AutomatedFarfield()
... fl.Freestream(
...     entities=[auto_farfield.farfield],
...     turbulence_quantities= fl.TurbulenceQuantities(
...         modified_viscosity_ratio=10,
...     )
... )

Attributes

entities: EntityList[Surface, MirroredSurface, GhostSurface, WindTunnelGhostSurface, GhostSphere, GhostCircularPlane]#

List of boundaries with the Freestream boundary condition imposed.

turbulence_quantities: TurbulentViscosityRatio | TurbulentKineticEnergy | TurbulentIntensity | TurbulentLengthScale | ModifiedTurbulentViscosityRatio | ModifiedTurbulentViscosity | SpecificDissipationRateAndTurbulentKineticEnergy | TurbulentViscosityRatioAndTurbulentKineticEnergy | TurbulentLengthScaleAndTurbulentKineticEnergy | TurbulentIntensityAndSpecificDissipationRate | TurbulentIntensityAndTurbulentViscosityRatio | TurbulentIntensityAndTurbulentLengthScale | SpecificDissipationRateAndTurbulentViscosityRatio | SpecificDissipationRateAndTurbulentLengthScale | TurbulentViscosityRatioAndTurbulentLengthScale, optional#

The turbulence related quantities definition.See TurbulenceQuantities() documentation.

Default:

None

name: str, optional#

Name of the Freestream boundary condition.

Default:

'Freestream'

velocity: tuple[str, str, str] | Expression | Velocity.Vector3, optional#

The default values are set according to the AerospaceCondition.alpha and AerospaceCondition.beta angles. Optionally, provide a legacy expression for each component or one compile-time expression for the velocity vector.

Default:

None

Methods

classmethod remap_symmetric_to_user_name(value)#

Remap ‘symmetric’ ghost entity to user’s symmetry surface name for UDF backward compat.

classmethod ensure_surface_existence(value)#

Ensure all boundaries will be present after mesher