AdditiveFOAM

AdditiveFOAM is a free, open source heat and mass transfer software for simulations of Additive Manufacturing (AM) released by Oak Ridge National Laboratory. It is built upon OpenFOAM, a free, open source computational fluid dynamics (CFD) software package released by the OpenFOAM Foundation.

Citing

If you use AdditiveFoam in your work, please cite the source code. Also, please consider citing relevant AdditiveFOAM Publications listed below.

Contributors

Publications

Some select publications using AdditiveFOAM are provided:

Repository Features

Link	Description
solver	Development version of the solver
utilities	Utilities for post-processing and code wrappers
tutorials	Tutorial cases based on NIST AMB2018 single tracks

Installation

AdditiveFOAM is built on source code released by the OpenFOAM Foundation openfoam.org, which is accessible to the public through the OpenFOAM source code repositories at Github. The current supported version is OpenFOAM-10, which can be compiled from source code following the steps provided by the OpenFOAM Foundation Documentation.

Once OpenFOAM-10 is compiled, perform the following steps:

Clone the AdditiveFOAM repository into the OpenFOAM project installation directory WM_PROJECT_INST_DIR:
```
cd $WM_PROJECT_INST_DIR
git clone https://github.com/ORNL/AdditiveFOAM.git
```

Build the movingHeatSource library and the additiveFoam executable:

cd $WM_PROJECT_INST_DIR/AdditiveFOAM/applications/solvers/additiveFoam/movingHeatSource
wmake libso
cd $WM_PROJECT_INST_DIR/AdditiveFOAM/applications/solvers/additiveFoam
wmake

Documentation

To run an AdditiveFOAM simulation, it is recommended to perform the following steps:

Prepare the case directory structure using a provided template:

mkdir -p $FOAM_RUN/additivefoam
cd $FOAM_RUN/additivefoam
cp -r $WM_PROJECT_INST_DIR/AdditiveFOAM/tutorials/AMB2018-02-B userCase
cd userCase

Modify the necessary input files according to your simulation requirements. These files include:
- constant/: Contains configuration and settings that define geometric and material conditions, including:
  - transportProperties: Sets the transport properties of the material. The thermal conductivity kappa and specific heat Cp are given as temperature dependent second-order polynomials for each phase in the material.
    
    The available phases are:
    - solid
    - liquid
    - powder
    The remaining properties are all assumed constant throughout the simulation.
  - heatSourceDict: Defines number, types, and paths of moving heat sources in the simulation.
    
    The available heat sources are:
    - superGaussian
    - modifiedSuperGaussian
    The available absorption models are:
    - constant
    - Kelly
    Each heat source model has the ability to be update the depth of the heat source for keyhole modeling, by setting the transient flag to True and defining an isoValue to track the depth of an isotherm contained within the heat source radius. An example of this usage is provided in the multiBeam tutorial.
- 0/: Contains the initial fields. The available fields are provided in the files:
  - T: temperature
  - U: velocity
  - p_rgh: reduced pressure
  - alpha.solid: solid volume fraction
  - alpha.powder: powder volume fraction
- system/: Contains simulation configuration files.
  - controlDict: Set simulation time settings and numerical parameters.
  - fvSchemes: Set the discretization schemes used to solve the governing equations
  - fvSolution: Set solution algorithms and convergence criterias. Note: fluid flow can be turned off by setting nOuterCorrectors to 0 in the PIMPLE dictionary.
Run the simulation: An example run script which creates a mesh, decomposes the mesh across multiple processors, and runs the AdditiveFOAM case in parallel using MPI is provided in tutorial Allrun script.
Visualize and post-process the results using ParaView
```
touch case.foam
paraview case.foam
```

Creating Scan Path Files

AdditiveFOAM supports a scan path file format that decomposes the laser path into segments that are either a) line sources or b) point sources.

Column	Description
Column 1	mode = 0 for line source, mode = 1 for point source
Columns 2-4	(x,y,z) coordinates in meters. For a line (mode = 0), this is the final position of the line raster. For a spot (mode = 1), this is the constant position of the laser
Column 5	Value for laser power in watts
Column 6	For a line (mode = 0), this is the velocity of the laser in meters/second. For a point (mode = 1), this is the dwell time of the laser in seconds

Exporting ExaCA Data

One feature of AdditiveFOAM is its ability to export thermal information to ExaCA, a cellular automata (CA) code for grain growth under additive manufacturing conditions. This feature is enabled using the execute flag in the constant/foamToExaCADict file. The solidification conditions at the specified isotherm is tracked in the represenative volume element defined by box and a resolution defined by dx. It is recommended to track the liquidus isotherm. Users should be warned that this interpolation may cause a significant load-balancing issues if the resolution of the ExaCA data is much finer than that of the AdditiveFOAM mesh, and therefore, this feature should be used selectively.

License

AdditiveFOAM is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. See the file LICENSE in this directory or http://www.gnu.org/licenses/, for a description of the GNU General Public License terms under which you can copy the files.

Contact

For any questions, issues, or suggestions regarding AdditiveFOAM, you can reach out to the project maintainers through the GitHub repository's issue tracker or by contacting the development team in the Contributors links above.

We appreciate your interest in AdditiveFOAM and look forward to your contributions!

streeve / AdditiveFOAM