I have been working for some time on the development of an improved version of the Euler-Euler two-fluid solver in OpenFOAM®, in order to improve its stability when a dense granular phases is present. An initial version of the solver, derived from twoPhaseEulerFoam, with the following modifications
- Adoption of the PIMPLE (PISO/SIMPLE) algorithm instead than PISO, to allow equation under-relaxation and ensure the convergence of all the equations at each time-step
- Solution of the momentum predictor, accounting for the strongly varying terms using flux-reconstruction
is available on github. You can download it by typing
- git clone git://github.com/AlbertoPa/twoPhaseEulerPimpleFoam.git
and keep it up to date typing
- git pull
in a terminal opened in the base directory containing the solver.
To build the solver, simply type ./Allwmake in the directory containing the source code. The executable is named twoPhaseEulerPimpleFoam, and is stored in $FOAM_USER_APPBIN.
Two test-cases are provided, showing how to set them up. The tutorial called fallingBlockFine shows some difficulties of the solution algorithm when sharp interfaces are present in granular flows. This problem has been fixed in the development tree of the code, which is currently under testing and further development, and will be released when ready (interpret this as: when Alberto is happy, all test-cases are passed and all the known critical bugs are fixed :-D). The release will include, progressively, the following changes:
- Conservative form of the momentum equation
- Implementation of the partial elimination algorithm to improve the robustness of phase coupling
- Stabilization of the particle pressure term when kinetic theory and frictional models are activated
- Implementation of additional sub-models for the description of gas-particle flows
As a longer term goal, the code will be extended to manage an arbitrary number of phases, and advanced models for the particulate phase will be implemented.
Volunteers are always welcome to contribute, even only suggestions and comments.
Thanks. 🙂
This offering is not approved or endorsed by OpenCFD Limited, the producer of the OpenFOAM software and owner of the OPENFOAM®  and OpenCFD®  trade marks. I am not an OpenFOAM developer, but I develop with OpenFOAM technology.