Output Variables
This section describes the outputs you can obtain from the Flow module. The following types of data are available for output from the Flow module:
Primary Variables
Properties
Derived Variables
Boundary Variables
Integrated Quantities
Pressure Distribution
Velocity Distribution
Output of Primary Variables
Primary variables are the fundamental variables for a given set of modules and models. They are required as part of the solution.
Primary Variables for Flow Module
Label in Results Panel Variables List
Label in GUI X-Y Plot Menu
Label in points.txt
Label in integral.txt
Definition
Units
Display or Output Options
Pressure
Pressure
P_
NA
Pressure at a point
N/m2
At a Point and in the GUI Display Window
Velocity X
Velocity X
u_
NA
Cartesian velocity component in X direction
m/s
Same
Velocity Y
Velocity Y
v_
NA
Cartesian velocity component in Y direction
m/s
Same
Velocity Z
Velocity Z
w_
NA
Cartesian velocity component in Z direction
m/s
Same
Primary variables are automatically activated for selected geometric entities such as boundaries, derived surfaces, interfaces, streamlines, particles, or volumes depending on the modules and models that are selected.
Output of Property Variables
Property variables are the physical properties for the fluids and solids in the domain. They are required as part of the solution.
Physical Properties for Flow Module
Label in Results Panel Variables List
Label in GUI X-Y Plot Menu
Label in points.txt
Label in integral.txt
Definition
Units
Display or Output Options
Density
NA
rho_
NA
Effective density
N/m2
At a Point and in the GUI Display Window
Viscosity
Viscosity
mu_
NA
Effective viscosity
m/s
At a Point and in the GUI Display Window
Physical property output for the Flow module is automatically activated for selected volumes and boundaries, except point probes, depending on the models that are selected.
Output of Derived Variables
Derived variables are engineering data computed from the primary variables. While not required as part of the solution, they can provide valuable information for analysis of the results.
Derived Variables for Flow Module
Label in Results Panel Variables List
Label in GUI X-Y Plot Menu
Label in points.txt
Units
Display or Output Options
Comments
Mach Number
Mach Number
mach_
-
At a Point and in the GUI Display Window
Compressible only
Speed of Sound
Speed of Sound
sspd
m/s
Same
Compressible only
Total Pressure
Total Pressure
totalP_
Pa
Same
Velocity Magnitude
Velocity Magnitude
vMag_
m/s
Same
Vorticity Magnitude
Vorticity Magnitude
vorticityMag
1/s
Same
Vorticity X, Y, Z
Vorticity X
vorticity_x_
1/s
Same
Radial Velocity
Radial Velocity
labVr
m/s
Same
Tangential Velocity
Tangential Velocity
labVt
m/s
Same
Axial Velocity
Axial Velocity
labVa
m/s
Same
Relative Velocity Magnitude
Relative Velocity Magnitude
vrMag
m/s
Same
Multi reference frame
Relative Radial Velocity
Relative Radial Velocity
relVr
m/s
Same
Multi reference frame
Relative Tangential Velocity
Relative Tangential Velocity
relVt
m/s
Same
Multi reference frame
Relative Axial Velocity
Relative Axial Velocity
relVa
m/s
Same
Multi reference frame
Strain
Strain
strain
1/s
Same
Derived variable output for the Flow module is automatically activated for selected volumes and boundaries, (other than point probes) depending on the models that are selected.
Output of Boundary Variables
Boundary variables are data associated with a Boundary. You can integrate primary and derived variables over a selected Boundary The quantities available for output for the boundary for the Flow module depend on the boundary type.
Integrated Boundary Outputs (Closed Boundaries) for Flow Module
Output Quantity
Flow Module Boundary Type
Rotating Wall
Symmetry
Wall
Area
Yes
Yes
Yes
Normal
Yes
Yes
Yes
Average Static Pressure
Yes
Yes
Average Total Pressure
Yes
Yes
Mass Averaged Total Pressure
Yes
Yes
Power
Yes
Yes
Pressure Distribution
Yes
Yes
Pressure Force
Yes
Yes
Torque in Axis Direction
Yes
Yes
Torque
Yes
Yes
Viscous Force
Yes
Yes
Integrated Boundary Outputs (Open Boundaries) for Flow Module
Output Quantity
Flow Module Boundary Type
Resistor Capacitor
Specified Pressure Inlet
Specified Pressure Outlet
Specified Total Pressure
Specified Velocity
Specified Volumetric Flux
Area
Yes
Yes
Yes
Yes
Yes
Yes
Normal
Yes
Yes
Yes
Yes
Yes
Yes
Average Static Pressure
Yes
Yes
Yes
Yes
Yes
Yes
Average Total Pressure
Yes
Yes
Yes
Yes
Yes
Yes
Mass Averaged Total Pressure
Yes
Yes
Yes
Yes
Yes
Yes
Mass Flow Rate
Yes
Yes
Yes
Yes
Yes
Yes
Momentum
Yes
Yes
Yes
Yes
Yes
Yes
Pressure Force
Yes
Yes
Yes
Yes
Yes
Yes
Volumetric Flow Rate
Yes
Yes
Yes
Yes
Yes
Yes
You can activate the required output for a selected boundary under the Flow module in the Properties panel.
Boundary Variables for Flow Module
Label in Results Panel Variables List
Label in GUI X-Y Plot Menu
Label in points.txt
Label in integral.txt
Definition
Units
Display or Output Options
Wall Displacement
NA
NA
NA
Wall displacement for a flexible wall
At a Point and in the GUI Display Window
In the GUI Display Window
Wall Velocity
NA
NA
NA
Wall velocity for a flexible wall
Same
In the GUI Display Window
Output of Integrated Quantities
Integrated output are quantities that are integrated over a Boundary, Interface, or Volume.
Integrated Quantities for Flow Module
Label in Properties Panel Output Choices
Label in GUI X-Y Plot Menu
Label in integral.txt
Units
Definition
Relevant Geometric Entity
Area*
Area*
area_t
m2
Area
Boundaries and Interfaces
Average Static Pressure or Pressure
Average Static Pressure
p_
N/m2
Average static pressure
Open Boundaries, Interfaces and Volumes
Average Total Pressure or Total Pressure
Average Total Pressure
pt_
N/m2
Average total pressure
Boundaries and Interfaces
Mass Averaged Total Pressure
Mass Averaged Total Pressure
mpt_
N/m2
Mass averaged total pressure
Open Boundaries and Interfaces
Mass Flow Rate
Mass Flux
q_
kg/s
Instantaneous mass flux
Open Boundaries and Interfaces
Momentum
Momentum X
Momentum Y
Momentum Z
mx_
my_
mz_
kg-m/s
X, Y, Z components of momentum flux
Open Boundaries, Interfaces and Volumes
Normal
Normal X
Normal Y
Normal Z
norm_x
norm_y
norm_z
Normalized
X, Y, Z component of the surface normal
Boundaries and Interfaces
Power
Power
pow_
Watts
Instantaneous Power
Solid Boundaries
Pressure Force
Pressure Force X
Pressure Force Y
Pressure Force Z
px_
py_
pz_
N
Instantaneous pressure force in X, Y, Z direction
Boundaries and Interfaces
Revolution Average Mass Flux
Revolution Average Mass Flux
qa_
kg/s
Revolution averaged mass flux
Boundaries, when using RPM for the timestep
Revolution Average Power
Revolution Average Power
powa_
watts
Revolution averaged power
Rotating Components
Revolution Average Volume Flux
Revolution Average Volume Flux
qva_
Gallons/min
Revolution averaged volumetric flux
Boundaries, when using RPM for the timestep
Shear Force
Shear Force X
Shear Force Y
Shear Force Z
tx_
ty_
tz_
N
X, Y, Z components of shear
Solid Boundaries
Torque
Torque X
Torque Y
Torque Z
torqx_
torqy_
torqz_
N-m
X, Y, Z components of torque around a specified center
Solid Boundaries
Torque in Axis Direction
Torque
torq_
N-m
Torque of rotating component about its rotation vector
Rotating components
Velocity
Velocity X
Velocity Y
Velocity Z
u_
v_
w_
N
Average velocity in X, Y, Z direction
Volumes
Viscous Force
Shear Force X
Shear Force Y
Shear Force Z
tx_
ty_
tz_
N
Instantaneous shear force in X, Y, Z direction
Solid Boundaries
Volumetric Flow Rate
Volumetric Flux
qv_
m3/s
Instantaneous volumetric flux
Boundaries and Interfaces