alphaInitializerFoam

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:warning: IMPORTANT :warning: The alphaInitializerFoam has been renamed as setVofField and is available at geometricVofExt.

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Introduction

alphaInitializerFoam is a pre-processing utility designed to initialize the alpha (VOF) field with an input shape surface mesh in .stl format. It works on polyhedral unstructured meshes. The previous fluid shape will be retained.

Another copy of alphaInitializerFoam and demo cases can be found in:

Dai, Dezhi (2019), “alphaInitializerFoam”, Mendeley Data, v2

http://dx.doi.org/10.17632/wg4sx7sc57.2

Compatibility

The source code of alphaInitializerFoam is developed and maintained for the latest OpenFOAM-plus release (currently OpenFOAM-v1812). A script for generating code for other releases and old versions will be provided in the near future.

Please notify me via the email address below if you found any errors or bugs, and I will fix them as soon as possible.

Methodology

The basic idea of alphaInitializerFoam follows:

• first compute the intersection of the surface mesh (blue), which represents the liquid or gas shape, and each cell (red) in the mesh,

<img src="https://upload.wikimedia.org/wikipedia/commons/4/4a/Boolean_union.PNG" width="200"><img src="https://upload.wikimedia.org/wikipedia/commons/0/0b/Boolean_intersect.PNG" width="200">Figures are from Wikipedia.

• then initialize the fraction value by normalizing the intersection volume with the cell one.

The .stl surface mesh loading and intersection operation in alphaInitializerFoam are from libigl and Cork libs, respectively.

It should be noted that the copies of Eigen, libigl and Cork that provided together with alphaInitializerFoam are ONLY used for simplifying the installation.

Installation

Before compiling alphaInitializerFoam, make sure that the OpenFOAM environment has been set properly.

1. Download alphaInitializerFoam from this page or http://dx.doi.org/10.17632/wg4sx7sc57.2

2. Build libcork.a

cd cork
make

3. Build alphaInitializerFoam

cd ..
wmake

All of the compiling commands above have been integrated into Allwmake script.

Usage

The usage of alphaInitializerFoam is simple:

Usage: alphaInitializerFoam [OPTIONS] <stl-file>
Arguments:
  <stl-file>        The input surface mesh in .stl format
Options:
  -case <dir>       Specify case directory to use (instead of the cwd)
  -gas              Initialize the shape for gas phase
  -doc              Display documentation in browser
  -doc-source       Display source code in browser
  -help             Display short help and exit
  -help-compat      Display compatibility options and exit
  -help-full        Display full help and exit

Initialize the alpha (VOF) field with an input shape surface mesh in .stl
format. The previous fluid shape will be retained.

Using: OpenFOAM-v1812 (1812) (see www.OpenFOAM.com)
Build: v1812
Arch:  LSB;label=32;scalar=64

It should be noted that the parallel option has been disabled.

Demos

Three demo cases are available in http://dx.doi.org/10.17632/wg4sx7sc57.2 (alphaInitializerFoamTut.tar.gz).

The commands are integrated into the Allrun script for each case.

damBreak

<img src="https://i.imgur.com/xQNh65O.png"> <img src="https://i.imgur.com/B8hqsuZ.png"> <img src="https://i.imgur.com/qhpNmFU.png">

dualPiBubble

<img src="https://i.imgur.com/utTNzC1.png">

dualPiDroplet

<img src="https://i.imgur.com/Dmr2J6h.png">

Attribution

If you use alphaInitializerFoam in your academic projects, please cite this utility in general, you could use this BibTex entry:

@misc{alphaInitializerFoam,
  doi = {10.17632/wg4sx7sc57.2},
  url = {http://dx.doi.org/10.17632/wg4sx7sc57.2},
  author = {Dai, Dezhi},
  title = {alphaInitializerFoam},
  publisher = {Mendeley Data, v2},
  year = {2019}
}

Change Log

06/20/2019

• Add support to wave model boundaries. Thanks for guohuiqun @ cfd-china.

06/11/2019

• Initial release.

Contributors

• Dezhi Dai, UT Arlington, dezhi.dai@mavs.uta.edu (Developer)