ETH-OFTools-2.3.X

Chair of Building Physics (ETH Zurich) addons for OpenFOAM-2.3.x.

Version:

Authors:

• Marc Immer
• Marcel Vonlanthen

Contributors:

• Lukas Lebovitz

How to cite:

If you use the Filtered Noise Inflow Generator BC (FilteredNoiseInflowGenerator or FilteredNoiseInflowGeneratorScalar), please cite the following: Immer, Marc Christian. Time-resolved measurement and simulation of local scale turbulent urban flow. ETH-Zürich (2016). http://dx.doi.org/10.3929/ethz-a-010657618

Installation:

Exectute the following lines in a terminal to install all the addons. Each addon can be installed separately by executing wmake in its folder.

1. git clone https://github.com/ETH-BuildingPhysics/ETH-OFTools-2.3.X.git
2. cd ETH-OFTools-2.3.X
3. git checkout -b development remotes/origin/development
4. ./Allwmake

Contents

Boundary Conditions

• FilteredNoiseInflowGenerator
  Variant of Kleins Filtered Noise turbulent inflow boundary condition Documentation is available in the Doctoral Thesis: http://e-collection.library.ethz.ch/view/eth:49140
• FilteredNoiseInflowGeneratorScalar
  Variant FilteredNoiseInflowGenerator including turbulent scalar generation http://dx.doi.org/10.3929/ethz-a-010657618
• LEMOSinflowGeneratorMod
  Modification of https://github.com/LEMOS-Rostock/LEMOS-2.3.x/tree/master/libLEMOS-2.3.x/boundaryConditions/inflowGenerator to read input files similar to the OpenFOAM BC TimeVaryingMappedFixedValue
• nestedBlendedVelocity
  Nested boundary condition for the velocity. To use with a nested solver.

Function Objects

• CnC
  Job control function object
• scalarVelocityProduct
  Creates the field Us, where s is any scalar field. Must be placed before the OpenFOAM function object fieldAverage, to get the averaged UsMean field. Useful to get the fields required for scalarCovariance
• timeAbort
  Job control function object

Python tools

Sampling libraries

• foamFileSmall
  Similar to the file format foamFile, however does not save the points and faces. Useful for runtime sampling of surfaces if mesh does not change.
• hdf5
  New surface file type: hdf5. Saves a surface as a h5 file. Needs the hdf5 library installed

Solvers

• nestedImpBlendDsPimpleFoam
  One-way, downscale, nested solver with an implicit blending at the nested boundaries. It solves the Navier-Stokes equation with the pimple algorithm. The turbulence model can be laminar, RANS or LES. The solver has nesting cascade capabilities.
• pisoScalarSourceFoam230
  The OpenFOAM pisoFoam solver with passive scalar transport of an arbitrary number of scalars. The list of scalars to be solved is defined in the transportProperties as: scalars ( A B C ); a generic boundary condition can be defined with the file 0/sdefault. Use fvOptions do define sources. Also writes the product field Us, to be used with runtime averaging and the utility scalarCovariance

Utilities

• cellVolumes
  Save the cell volumes into a file cellVolumes
• gradU
  saves the fields gradU and gradUMean of the internal field (not at boundaries)
• LESdelta
  saves the LES filter width sgsModel->delta() in the field LESdelta
• postAvg
  Averages scalar fields, saves the averaged field with the postfix Mean. E.g nuSgs will be saved as nuSgsMean
• Q2D
  Similar to Q, but sets the off-plane components of the velocity gradient tensor to zero (off-plane is z component). Emulates what a Stereo-PIV system would measure.
• resLES
  Useful for analyzing statistics of LES computations. Needs the fields UMean,UPrime2Mean and kMean. Outputs TKE in TKEMean, the ratio of resolved TKE to total TKE in resLES and the production of resolved TKE in TKEMeanProd
• scalarCovariance
  To compute the scalar covariance, e.g the turbulent temperatur flux <u'T'> is written to UPrimeTPrimeMean, calculated by UTMean - (UMean * TMean). Important: the product field UT must be sampled and averaged!
• scalarFluxes
  Used in combination with the pisoScalarSourceFoam230 solver. Not needed with proper runtime averaging and the scalarCovariance utility
• SGSValues
  For LES. Saves the production of subgrid TKE in a field kSgsProd. Computed using 2.0 * nuSgs * magSqr(symm(gradU)));
• snGradU
• TKEProd2D
• yPlusMeanLES
  Compute yPlus mean for a LES. The fields UMean, nuSgsMean must exist. They can be created with the default OpenFOAM functionObject fieldAverage. If nuSgsMean does not exist, it can be created with postAvg