Foam Construction Module

Integrates Foam construction utility into the MoDeNa software framework. More...

Modules
	C++ Source Code
	Source Code Documentation.

Namespaces
	FoamConstruction
	Module definition of the Foam construction utility.
	FoamConstruction.FoamGeometryConstruction_Periodic
	Packing and tesselation.
	FoamConstruction.periodicBox
	Moves foam into a periodic box.
	FoamConstruction.run
	Python script, which organizes creation of the foam.
	FoamConstruction.vtkconv
	Converts binary VTK to ASCII VTK file.

Detailed Description

Integrates Foam construction utility into the MoDeNa software framework.

Creates files describing the morphology of foam with desired number of cells, cell size distribution, porosity and strut content.

README

Foam Construction

Scope of this module

This module contains an utility, which can create a spatially three-dimensional image of foam morphology with desired foam density, cell size distribution and strut content. This module does not contain any MoDeNa model.

Installation

The code depends on several third-party applications. They are listed in Dependencies of Foam construction utility.To install all of these on Ubuntu, do:

sudo apt-get install libmatheval-dev gmsh gsl-bin libgsl0-dev python-vtk \
    lib3ds-1-3 libjpeg62 freeglut3 libnlopt-dev libboost-dev \ libboost-date-time-dev libboost-thread-dev zlib1g-dev libpng12-dev \
    libjpeg8-dev libtiff5-dev libopenexr-dev

Then download and install neper from http://neper.sourceforge.net/downloads.html. You will need to unpack neper, go to its src folder and then:

mkdir build
cd build
cmake ..
make
sudo make install

Install POV-Ray from sources:

cd where-you-want-source-files
git clone https://github.com/POV-Ray/povray.git
cd povray/unix
./prebuild.sh
cd ..
./configure COMPILED_BY="your name <email@address>"
make
sudo make install

Download meshconv from http://www.patrickmin.com/meshconv/, download binvox from http://www.patrickmin.com/binvox/ and copy meshconv and binvox to $PATH. You can do this manually or in terminal using

wget http://www.patrickmin.com/meshconv/linux64/meshconv
chmod +x meshconv
sudo mv meshconv /usr/local/bin/meshconv
wget http://www.patrickmin.com/binvox/linux64/binvox
chmod +x binvox
sudo mv binvox /usr/local/bin/binvox

To install voro++:

cd foamreconstr
sudo ./install_voro++.sh

If that doesn't work, you will need to download it from http://math.lbl.gov/voro++/download/ and install it manually.To compile foamreconstr go to foamreconstr/ folder and:

cmake .
make

Files

The folder FoamConstruction contains following files:

• FoamGeometryConstruction_Periodic.py - tessellation, creation of RVE
• periodicBox.py - creation of the box with periodic boundary conditions
• vtkconv.py - conversion from binary vtk to ascii vtk
• run - main executable script

All files must be in one directory.

Inputs

The code is controlled by the input.json file, which must be located in the root of FoamConstruction folder. Default input file can be found in example_inputs directory. Following inputs can be adjusted:

• MU - mean of cell size distribution
• SIGMA - standard deviation of cell size distribution
• NumOfCells - number of cells in RVE (representative volume element)
• porosity - desired porosity of voxelized foam
• strutContent - desired strut content of voxelized foam
• filename - name of the output file with RVE
• deleteFiles - delete some redundant output files after execution
• packing - call packing algorithm, which creates seeds and radii for tessellation
• alternativePackingAlgorithm - uses alternative packing algorithm from "spherepack"
• tesselation - call tessellation program, which creates foam with desired cell size distribution based on results of packing
• visualizeTesselation - visualizes tessellation using the POV-Ray
• geometry - limits the foam to RVE
• statistics - compute and save cell volumes, face surfaces, etc.
• hypermesh - create input for Hypermesh
• moveToPeriodicBox - move RVE to box with periodic boundary conditions
• renderBox - show the box with periodic boundary conditions
• binarizeBox - voxelize the box with periodic boundary conditions

Execution

Prepare input.json, then:

./run.py

Optimizing porosity and strut content of voxelized foam is relatively time consuming. You can switch to Bounded method if you approximately know the size of the box in voxels (usually form experience with the program). In that case you need to edit the run script.

Outputs

Several output files are created:

• PeriodicRVE.geo which is the periodic geometry of foam in .GEO format.
• CellVolumes_PeriodicRVE.txt containing the volumes of all the cells in RVE.
• FaceAreas_PeriodicRVE.txt containing the areas of all the faces in RVE.
• EdgeLengths_PeriodicRVE.txt containing the lengths of all the edges in RVE.
• HyperMeshinput.cmf which is a input file for Hypermesh to recreate the geometry.
• PeriodicRVEBox.stl - surface mesh of the box with periodic boundary conditions
• PeriodicRVEBox.ply - surface mesh of the box with periodic boundary conditions
• PeriodicRVEBox.vtk - voxelized version of the box with periodic boundary conditions - main output for foam with no struts
• PeriodicRVEBox-ascii.vtk - voxelized version of the box with periodic boundary conditions - ascii version
• PeriodicRVEBoxStruts.vtk - voxelized version of the box with periodic boundary conditions - main output for foam with struts

Generally, .geo files can be viewed with gmsh, .stl, .ply and .vtk files can be viewed with paraview.