Contents
1 Introduction
- Source code repository
- perturbU at GitHub
- Description
- A few utilities for initializing fields for LES simulations for OpenFOAM.
- These utilities were created by Eugene de Villiers and are related to his PhD Thesis "The Potential of Large Eddy Simulation for the Modeling of Wall Bounded Flows", available here.
- The repository perturbU at GitHub has been created by Bruno Santos (wyldckat) to assist in maintaining an easier way to keep updating the code to be usable with the latest OpenFOAM versions.
- Original sources for these utilities:
- perturbUChannel: LES - post #34
- perturbUCylinder: LES turbulent pipe flow - post #2
- perturbUGeneric: LES turbulent pipe flow - post #26
- Support pages
-
- Issue/bug tracker: perturbU Issue Tracker
- Forum support thread: PerturbU
2 Installation
Valid versions: 
Template:Version1906
The installation depends on the way you download the source code:
2.1 Using Git
- Go to your user folder:
mkdir -p $FOAM_RUN cd $FOAM_RUN/..
- Clone the repository and go into the cloned repository:
git clone https://github.com/wyldckat/perturbU.git cd perturbU - Checkout the repository respective to the version of OpenFOAM you are using:
- OpenFOAM.com v1906 and newer :
git checkout OFcom1906
- OpenFOAM.org 8 and newer (might work with OpenFOAM 6 and 7):
git checkout OF8
- OpenFOAM.org 4.0 and newer:
git checkout OF4x
- OpenFOAM.org 3.0 to 3.0.x:
git checkout OF30x
- OpenFOAM.org 2.0 to 2.4:
git checkout OF20x
- OpenFOAM 1.7 and older:
git checkout OF17x
- Build perturbU* utilities by running:
wmake all
2.2 Using Zip
- Go to your user folder:
mkdir -p $FOAM_RUN cd $FOAM_RUN/..
- Get the Zip file for the repository respective to the version of OpenFOAM you are using:
- OpenFOAM.com v1906 and newer :
wget https://github.com/wyldckat/perturbU/archive/OFcom1906.zip -O perturbU.zip
- OpenFOAM.org 8 and newer (might work with OpenFOAM 6 and 7):
wget https://github.com/wyldckat/perturbU/archive/OF8.zip -O perturbU.zip
- OpenFOAM 4.0 and newer:
wget https://github.com/wyldckat/perturbU/archive/OF4x.zip -O perturbU.zip
- OpenFOAM 3.0 to 3.0.x:
wget https://github.com/wyldckat/perturbU/archive/OF30x.zip -O perturbU.zip
- OpenFOAM 2.0 to 2.4:
wget https://github.com/wyldckat/perturbU/archive/OF20x.zip -O perturbU.zip
- OpenFOAM 1.7 and older:
wget https://github.com/wyldckat/perturbU/archive/OF17x.zip -O perturbU.zip
- Unzip the respective file and go into the respective folder, for example:
unzip perturbU.zip mv perturbU-OF20x perturbU cd perturbU - Build perturbU* utilities by running:
wmake all
3 Usage
- Assuming you've already followed the instructions given in the section Installation, then copy the file perturbUChannel/perturbUDict to your case folder's system sub-folder. For example, from within your case folder, run:
cp $FOAM_RUN/perturbU/perturbUChannel/perturbUDict system/ - Edit the file perturbUChannel/perturbUDict and adjust to your needs.
- Run the respective utility for your situation:
- For channel simulations:
perturbUChannel
- For cylinder simulations:
perturbUCylinder
- In theory, this should work for any simulation:
perturbUGeneric
- For channel simulations:
3.1 Usage Notes
3.1.1 Getting a turbulent field in steady-state
Source: PerturbU - post #26 Quoting from the post:
The default perturbUDict has the bulk velocity set to false. As Eugene mentions in his thesis this would lead to damping the perturbations, to get a turbulent field in steady state set it back to true.
3.1.2 Problems with transportProperties file
Valid versions:
Source: PerturbU - post #26
perturbUChannel complains about not being able to read the file constant/transportProperties. Therefore, try changing from something like this:
Ubar [0 1 -1 0 0 0 0] (0.1335 0 0); transportModel Newtonian; nu [0 2 -1 0 0 0 0] 2e-05;
to this:
Ubar Ubar [0 1 -1 0 0 0 0] (0.1335 0 0); transportModel Newtonian; nu nu [0 2 -1 0 0 0 0] 2e-05;
