Dear MFIX user,
We are pleased to announce the release of the new stable version of MFIX (MFIX2010-1). Please visit https://mfix.netl.doe.gov/members/download.php to download the latest version. Please see the attached release notes that highlight the changes from the previous version.
Please send any software related questions to mfix-help@mfix.netl.doe.gov or administrative questions toadmin@mfix.netl.doe.gov.
Regards,
MFIX Development Team
Changes from MFIX2007-4 (Date: 12/31/2007) to MFIX2010-1 (Date: 02/02/2010)
Changes in existing features:
- Bug fixes and enhancements:
- Solids inventory reporting problem for parallel runs
- Unit conversion from CGS to SI for dimensional quantities.
- Print format changes to accommodate processor counts > 100
- Enhancements:
- Semi-implicit treatment of IA conductivity term
- Conducted extensive debugging and verification of the DEM code
- Updated DEM test cases
- Updated documents:
- Equations document [1]
- Readme file [2]
New features added:
- HYS polydisperse drag model and test case
- The Holloway, Yin and Sundaresan (HYS) drag relation accounts for the effect of finite Reynolds number on the fluid-particle drag experienced by particles in polydisperse suspensions.
- The HYS drag model is described in mfix/doc/HYS_drag.pdf.
- DEM
- Expanded DEM code so particles of differing size and density can be modeled (polydispersity).
- Added a second order integration method (Adams Bashforth) to DEM as an option (DES_INTG_METHOD).
- Added the Hertzian collision model to DEM as an option (DES_COLL_MODEL).
- Created an updated user guide/document for the DEM code that includes a discussion on theory, numerics, and the verification tests [3]
- Cartesian Grid cut cell technique
- This new capability allows the definition of curved or sloping boundaries, instead of the usual stair-step representation.
- Computational cells are truncated at the wall to conform to the shape of the boundaries.
- The Cartesian grid technique is available for the Euler-Euler approach and includes no-slip and free-slip boundary conditions for either gas or solids phases.
- A user guide describing the utilization of the cut cell technique is located in mfix/doc/Cartesian_grid_user_guide.pdf [4].
- Some tutorials located at mfix/Cartesian_grid_tutorials illustrate the new capability.
- Distributed I/O
- Option to compile using gfortran
Under Development:
- GHD (Garzo, Hrenya, and Dufty) granular kinetic theory
- Code was updated with GHD granular kinetic theory and a simple shear flow case was added to tests/GHD to show how this model is used.
- The major difference between this theory and previous KT's that it solves mixture momentum and granular energy equations instead of the individual solids phases equations.
- Currently this theory is for granular flows (no fluid) and only simple wall BC can be applied (i.e. no slip, free slip)
- The effect of fluid-solid drag was included in the GHD theory.
- DEM
- Adding inlet/outlet capabilities to DEM
References
- S. Benyahia, M. Syamlal, T.J. O'Brien, "Summary of MFIX Equations", From URL
https://mfix.netl.doe.gov/documentation/MfixEquations2005-4-4.pdf, August 2009. - https://mfix.netl.doe.gov/documentation/Readme.pdf
- https://mfix.netl.doe.gov/documentation/dem_doc_2010.pdf
- https://mfix.netl.doe.gov/documentation/Cartesian_grid_user_guide.pdf