Difference between revisions of "OpenFOAM guide/Table of common fields"

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This table should give a list of the field names commonly written by the OpenFOAM-Solver.
 
This table should give a list of the field names commonly written by the OpenFOAM-Solver.
  
It was inspired by the discussion [http://tfdpc67.tfd.chalmers.se/foam/discus/messages/1/655.html?1117098392 What's the meaning of variables in the computed results] in the MessageBoard:
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It was inspired by the discussion [http://www.cfd-online.com/Forums/openfoam-post-processing/61422-whatbs-meaning-variables-computed-results.html What's the meaning of variables in the computed results] in the Forum:
  
{| border="1" cellpadding="2"
+
 
|+Fields written by OpenFOAM
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{| class="wikitable"
 +
|+ '''Fields written by OpenFOAM'''
 
|-
 
|-
 
! Filename !! Description !! Dimension
 
! Filename !! Description !! Dimension
Line 10: Line 11:
 
! U
 
! U
 
| Velocity  
 
| Velocity  
|| <math>\frac{m}{s}</math>
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| align="center" | <math>\frac{m}{s}</math>
 
|-
 
|-
 
! U_0
 
! U_0
| Velocity at previous timestep (needed for restarting higher order time-stepping schemes
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| Velocity at previous timestep (needed for restarting higher order time-stepping schemes)
|| <math>\frac{m}{s}</math>
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| align="center" | <math>\frac{m}{s}</math>
 +
|-
 +
! phi
 +
| Flow through cell faces. Depends on whether the solver is for incompressible or compressible flow.
 +
| align="center" | incompressible flow: <math>\frac{m^3}{s}</math> <hr> compressible flow: <math>\frac{kg}{s}</math>
 +
|-
 +
! p
 +
| Pressure.  For incompressible solvers (example:  simpleFoam), this field is actually the pressure normalized by constant fluid density.  To get true pressure, you need to multiply by the density of your fluid in post processing.  For compressible solvers, '''p''' is the true pressure.
 +
| align="center" | incompressible flow:  <math>\frac{m^2}{s^2}</math> <hr> compressible flow:  <math>\frac{kg}{ms^2}</math>
 +
|-
 +
! epsilon
 +
| Turbulence dissipation rate
 +
| align="center" | <math>\frac{m^2}{s^3}</math>
 +
|-
 +
! k
 +
| Turbulence kinetic energy
 +
| align="center" | <math>\frac{m^2}{s^2}</math>
 +
|-
 +
! rho
 +
| Gas density
 +
| align="center" | <math>\frac{kg}{m^3}</math>
 +
|-
 +
! alpha
 +
| Dispersed phase volume fraction
 +
| align="center" | (Dimensionless, usually <br> within the interval [0, 1])
 +
|-
 +
! Theta
 +
| Granular temperature
 +
| align="center" | <math>\frac{m^2}{s^2}</math>
 +
|-
 +
! rDeltaT
 +
| The inverse of the timestep.  For solvers that vary the local timestep (LTSInterFoam and similar) this indicates the local timestep.  This can be especially useful for debugging.  A high value of rDeltaT may indicate a need for further mesh refinement within a region.
 +
| align="center" | <math>s^{-1}</math>
 
|}
 
|}
 +
 +
[[Category:OpenFOAM overview]]

Latest revision as of 13:11, 30 June 2016

This table should give a list of the field names commonly written by the OpenFOAM-Solver.

It was inspired by the discussion What's the meaning of variables in the computed results in the Forum:


Fields written by OpenFOAM
Filename Description Dimension
U Velocity \frac{m}{s}
U_0 Velocity at previous timestep (needed for restarting higher order time-stepping schemes) \frac{m}{s}
phi Flow through cell faces. Depends on whether the solver is for incompressible or compressible flow. incompressible flow: \frac{m^3}{s}
compressible flow: \frac{kg}{s}
p Pressure. For incompressible solvers (example: simpleFoam), this field is actually the pressure normalized by constant fluid density. To get true pressure, you need to multiply by the density of your fluid in post processing. For compressible solvers, p is the true pressure. incompressible flow: \frac{m^2}{s^2}
compressible flow: \frac{kg}{ms^2}
epsilon Turbulence dissipation rate \frac{m^2}{s^3}
k Turbulence kinetic energy \frac{m^2}{s^2}
rho Gas density \frac{kg}{m^3}
alpha Dispersed phase volume fraction (Dimensionless, usually
within the interval [0, 1])
Theta Granular temperature \frac{m^2}{s^2}
rDeltaT The inverse of the timestep. For solvers that vary the local timestep (LTSInterFoam and similar) this indicates the local timestep. This can be especially useful for debugging. A high value of rDeltaT may indicate a need for further mesh refinement within a region. s^{-1}