Output Fields

Output Fields#

This page presents all the output fields supported by different output types, including, the surface and volume solutions, as well as slices, isosurfaces, probe/surface-integral monitors and UserDefinedField.

Universal Fields#

The following fields are supported by Surface, Volume, Slice and UserDefinedField types of output:

Name	Description
`Cp`	Coefficient of pressure. \(C_p=(\frac{p-p_\infty}{\frac{1}{2}\rho_\infty{U_{ref}}^2})\)
`Cpt`	Coefficient of total pressure \(C_{p_t}=(\frac{p_t-p_\infty}{\frac{1}{2}\rho_\infty{U_{ref}}^2})\)
`gradW`	Gradient of primitive solution
`kOmega`	k and omega when using the kOmegaSST model
`Mach`	Mach number
`mut`	Turbulent viscosity
`mutRatio`	Ratio between turbulent viscosity and freestream dynamic viscosity, \(\mu_t/{\mu_\infty}\)
`nuHat`	Spalart-Allmaras variable, nuHat
`primitiveVars`	Primitive solution, Outputs rho, u, v, w, p (density, 3 velocities and pressure)
`qcriterion`	Q criterion
`residualNavierStokes`	5 components of the N-S residual
`residualTransition`	Residual for the transition model
`residualTurbulence`	Residual for the turbulence model
`s`	Entropy
`solutionNavierStokes`	Solution for the N-S equation in conservative form
`solutionTransition`	Solution for the transition model
`solutionTurbulence`	Solution for the turbulence model
`T`	Temperature
`velocity`	Velocity vector divided by reference freestream velocity
`velocity_x`	Velocity X component divided by reference freestream velocity
`velocity_y`	Velocity Y component divided by reference freestream velocity
`velocity_z`	Velocity Z component divided by reference freestream velocity
`velocity_magnitude`	Velocity magnitude divided by reference freestream velocity
`pressure`	Pressure divided by reference freestream pressure
`vorticity`	Vorticity vector
`vorticityMagnitude`	Vorticity magnitude
`vorticity_x`	Vorticity X component
`vorticity_y`	Vorticity Y component
`vorticity_z`	Vorticity Z component
`wallDistance`	Wall distance
`numericalDissipationFactor`	Sensor showing where the numericalDissipationFactor has been increased
`residualHeatSolver`	Residual for the heat equation solver
`VelocityRelative`	Velocity vector from which velocity of a non-inertial frame is subtracted (velocity of the rotating zone) and is then divided by reference freestream velocity. Equals 0 on any no-slip walls within rotational blocks. More information can be found here.
`lowMachPreconditionerSensor`	Low-Mach preconditioner factor
`velocity_m_per_s`	Velocity in units of m/s
`velocity_x_m_per_s`	Velocity X component in units of m/s
`velocity_y_m_per_s`	Velocity Y component in units of m/s
`velocity_z_m_per_s`	Velocity Z component in units of m/s
`velocity_magnitude_m_per_s`	Velocity Magnitude in units of m/s
`pressure_pa`	Pressure in units of Pa

Volume and Slice Specific Fields#

The following fields are specifically supported by VolumeOutput and SliceOutput:

Name	Description
`betMetrics`	Outputs BET disk related metrics, including variables such as `VelocityRelative`, `AlphaRadians`, `CfAxial`, `CfCircumferential`, `TipLossFactor`, `LocalSolidityIntegralWeight` for all BETDisks with possible overlapping.
`betMetricsPerDisk`	Same as above but each BETdisk has its own `betMetrics` so overlapping is avoided.
`linearResidualNavierStokes`	Linear residual of Navier-Stokes solver
`linearResidualTurbulence`	Linear residual of turbulence solver
`linearResidualTransition`	Linear residual of transition solver
`SpalartAllmaras_DDES`	DDES output for Spalart-Allmaras solver
`kOmegaSST_DDES`	DDES output for kOmegaSST solver
`localCFL`	Local CFL number

Surface Specific Fields#

The following fields are specifically supported by SurfaceOutput and SurfaceProbeOutput:

Name	Description
`CfVec`	skin friction coefficient vector, = \(C_{f_{Vec}}[3]=\frac{\tau_{wall}[3]}{\frac{1}{2}\rho_\infty U_{ref}^2}\) where \(\tau_{wall}[3]\) is the 3-D wall shear stress vector
`Cf`	Magnitude of `CfVec`
`heatFlux`	Heat flux computed from nondimensional quantities. Multiply by \(\rho_\infty C_\infty^3\) to find the dimensional values.
`nodeNormals`	Wall normal direction (may not be a unit vector). Note: This variable does not support time averaging.
`nodeForcesPerUnitArea`	\(\frac{\tau_{viscous}[3]-(p-p_\infty)*normal[3]}{\rho_\infty C_\infty^2}\), where \(\tau_{viscous}[3]\) is the 3-D viscous stress vector and \(normal[3]\) is the 3-D unit normal vector pointing from solid to fluid
`yPlus`	Non-dimensional wall distance, \(y^+\)
`wallFunctionMetric`	(beta feature) : This metric is a local indicator of the quality of the wall model. A value less than 1.25 indicates a good estimation of the wall shear stress. Between 1.25 and 10 indicates lower confidence, and values greater than 10 are not reliable for wall shear stress estimation.
`heatTransferCoefficientStaticTemperature`	Surface heat transfer coefficient (static temperature as reference)
`heatTransferCoefficientTotalTemperature`	Surface heat transfer coefficient (total temperature as reference)
`wall_shear_stress_magnitude`	Wall shear stress magnitude
`wall_shear_stress_magnitude_pa`	Wall shear stress magnitude in units of Pa

IsoSurface Specific Fields#

The following fields are specifically supported by IsoSurfaceOutput:

Name	Description
`Mach`	Mach number
`qcriterion`	Q criterion
`s`	Entropy
`T`	Temperature
`Cp`	Coefficient of pressure
`Cpt`	Coefficient of total pressure
`mut`	Turbulent viscosity
`nuHat`	Spalart-Almaras variable
`vorticityMagnitude`	Vorticity magnitude
`vorticity_x`	Vorticity X component
`vorticity_y`	Vorticity Y component
`vorticity_z`	Vorticity Z component
`velocity_magnitude`	Velocity magnitude divided by reference freestream velocity
`velocity_x`	Velocity X component divided by reference freestream velocity
`velocity_y`	Velocity Y component divided by reference freestream velocity
`velocity_z`	Velocity Z component divided by reference freestream velocity

User Variables#

Another way to define output fields is to use UserVariable found in User Defined Expressions. User defined Variables can access multiple solver variables and undergo mathematical operations. Please refer to Variables section for more details about this feature as well as some usage examples.

User Defined Fields#

Users can use the UserDefinedField below to specify custom expressions to calculate outputs based on some solver variables. Please refer to the User Defined Postprocessing Tutorial for more details.

class UserDefinedField[source]#

Bases: Flow360BaseModel

Defines additional fields that can be used as output variables.

Example

Compute Mach using UserDefinedField (Showcase use, already supported in Output Fields):

>>> fl.UserDefinedField(
...     name="Mach_UDF",
...     expression="double Mach = sqrt(primitiveVars[1] * primitiveVars[1] + "
...     + "primitiveVars[2] * primitiveVars[2] + primitiveVars[3] * primitiveVars[3])"
...     + " / sqrt(gamma * primitiveVars[4] / primitiveVars[0]);",
... )

Compute PressureForce using UserDefinedField:

>>> fl.UserDefinedField(
...     name="PressureForce",
...     expression="double prel = primitiveVars[4] - pressureFreestream; "
...     + "PressureForce[0] = prel * nodeNormals[0]; "
...     + "PressureForce[1] = prel * nodeNormals[1]; "
...     + "PressureForce[2] = prel * nodeNormals[2];",
... )

type_name: Literal['UserDefinedField'] = 'UserDefinedField'#

name: str [Required]#: The name of the output field.

expression: Annotated[str, AfterValidator(func=process_expressions)] [Required]#

The mathematical expression for the field.

Constraints:

func = <function process_expressions at 0x75b1263d2320>