terms of the local barycentric coordinates of the current tetrahedron, rather than the global coordinate system. Barycentric tracking works on any mesh, irrespective of mesh quality. Particles do not get "lost", and tracking does not require ad-hoc "corrections" or "rescues" to function robustly, because the calculation of particle-face intersections is unambiguous and reproducible, even at small angles of incidence. Each particle position is defined by topology (i.e. the decomposed tet cell it is in) and geometry (i.e. where it is in the cell). No search operations are needed on restart or reconstruct, unlike when particle positions are stored in the global coordinate system. The particle positions file now contains particles' local coordinates and topology, rather than the global coordinates and cell. This change to the output format is not backwards compatible. Existing cases with Lagrangian data will not restart, but they will still run from time zero without any modification. This change was necessary in order to guarantee that the loaded particle is valid, and therefore fundamentally prevent "loss" and "search-failure" type bugs (e.g., 2517, 2442, 2286, 1836, 1461, 1341, 1097). The tracking functions have also been converted to function in terms of displacement, rather than end position. This helps remove floating point error issues, particularly towards the end of a tracking step. Wall bounded streamlines have been removed. The implementation proved incompatible with the new tracking algorithm. ParaView has a surface LIC plugin which provides equivalent, or better, functionality. Additionally, bug report <https://bugs.openfoam.org/view.php?id=2517> is resolved by this change.
README for OpenFOAM-dev
- About OpenFOAM
- Copyright
- Download and installation instructions
- Documentation
- Source code documentation
- OpenFOAM C++ Style Guide
- Reporting bugs in OpenFOAM
- Contacting the OpenFOAM Foundation
#
About OpenFOAM
OpenFOAM is a free, open source computational fluid dynamics (CFD) software package released by the OpenFOAM Foundation. It has a large user base across most areas of engineering and science, from both commercial and academic organisations. OpenFOAM has an extensive range of features to solve anything from complex fluid flows involving chemical reactions, turbulence and heat transfer, to solid dynamics and electromagnetics.
Copyright
OpenFOAM 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 COPYING 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.