Sig Multiphase
The German Special Interest Group on Multiphase Flows in OpenFOAM® was initiated at the Southern German user meeting "OpenFOAM® Stammtisch" in 2009.
Contents
1 Special Interest Group on Multiphase Flows in OpenFOAM
Special Interest Group on extend-project.de: Multiphase Flows
Please note: This offering is not approved or endorsed by OpenCFD® Limited, the producer of OpenFOAM® software and owner of the OpenFOAM® and OpenCFD® trademarks.
2 Objectives
- Identify common interests with OpenFOAM® for the different multiphase flow types, and plan joint activities.
- Develop OpenFOAM® for multiphase applications, including pre-processing, solution methods, and post-processing.
- Provide tutorials on how to produce accurate results using OpenFOAM® for multiphase flows.
- Distribute relevant validation test cases and corresponding OpenFOAM® applications.
- Use OpenFOAM® to develop Best Practice Guidelines for CFD for multiphase flows.
- Connect people with the same interest: OpenFOAM® and multiphase flows.
- Organize meetings, workshops and collaborations.
3 Guidelines
Source files and tutorial cases should be located in the OpenFOAM extensions on SourceForge.net under the SVN repository.
Detailed written reports and tutorials should be added to the workspaces below.
4 Work space for Tutorials
Please provide some additional tutorials along with some description in order to give a first help for new FOAMers!
4.1 Tutorials for particle based methods
The tutorials for particle based methods have moved to its own Wiki page.
5 Work space for Reports and Validation
5.1 Surface tracking validation suite
5.1.1 Validation cases from the scientific literature
The accuracy of two-phase DNS methods will significantly depend on the accuracy of the sub-algorithm used to evolve the interface between the immiscible fluids. In the literature, over time, standardized advection test cases have been developed:
- Zalesak disk rotation test case
Zalesak, Steven T. "Fully multidimensional flux-corrected transport algorithms for fluids." JCP (1979)
- Liovic shear test case
Liovic, Petar, et al. "A 3D unsplit-advection volume tracking algorithm with planarity-preserving interface reconstruction." CAF (2006)
- Enright deformation test case
Enright, Douglas, et al. "A hybrid particle level set method for improved interface capturing." JCP (2002)
- Aulisa 3D shear test case
Aulisa, Eugenio, et al. "Interface reconstruction with least-squares fit and split advection in three-dimensional Cartesian geometry." JCP (2007)
5.1.2 Software design of the validation suite
- There exist different versions of Foam and the validation suite should be decoupled from any version.
- There exist different surface tracking methods that are required to provide *same* quality in terms of accuracy and performance: advection errors (L1, L2), volume conservation and CPU time.
A possible solution to the validation suite design is to implement velocity potential functions as function objects, together with error evaluators into a separate function object library that compiles against all platform versions.
5.2 SourceForge validation database
For a comprehensive validation database for free-surface flows have a look into the OpenFOAM® extensions on SourceForge.net under the SVN repository. You will find
- Advection Tests (Cylinder in Vortex Flow, Zaleski's Disc)
- Spurious Currents (Droplet under zero-gravity conditions)
- Surface Tension Implementation (Oscillating Droplet)
- Overall Performance I (Dambreak Tests (with and without obstacle))
- Overall Performance II (Rising Bubble)
- Overall Performance III (Sloshing Tank (will be added soon))
Please find below a LaTeX template for typesetting technical reports describing the validation of OpenFOAM®'s top-level multiphase solvers. The template holds both FOAM-specific macros for finite volume and FOAM-specific macros for tensor notation in LaTeX in order to provide a reasonable basis for reports that provide detailed and comprehensive information on validation test cases for multiphase flows.
- LaTeX Technical Report Template for the SIG on Multiphase Flows in OpenFOAM® -- Download File:SIGonMultiphaseFlows-LaTeXTemplate.tar
If you are interested in working with us on the field of Multiphase Flows within the Special Interest Group, please download the provided report template / specific reports and complete or correct them where appropriate; add yourself to the list of authors and upload the new report version to this page. Please have a close look at the provided packages and macros, i.e. the pgfplots package enables any user of the above test cases to provide the original validation data (numerical values) to the community for re-use along with a illustrative plot within the report.
- Working group on extend-project: interFoam Working group
This group is for problems on the interFoam solver and solutions. This group's goal is to collect, sort and (if possible) solve problems of the interFoam solver. A discussion platform for this is the next OpenFOAM® Stammtisch (probably in Munich in Jan-Feb 2012), where the results will be presented and discussed.
6 Current projects
- Creating a two-phase surface tracking advection test suite
- Creation of a comprehensive validation database for particle flows (planned)
- Work on specific projects
- Organize the next meeting
