[FLASH-USERS] FLASH3.1 Release

[Anshu Dubey]

The Flash Center is pleased to announce the release of the
next version of the FLASH code, version 3.1. FLASH 3.1 offers
many new features, and a few bug-fixes  added since FLASH 3.0 release.
The new features of FLASH 3.1 are :

* Support for Paramesh 4, which includes operation of Paramesh in
 library mode.

* Major performance improvement in the Particles data movement algorithm
 released with 3.0, and a new Particles data movement algorithm which is
 more efficient in some situations.

* Support for multiple particle types in a single simulation. This has
 had limited testing.

* An algorithm to map paramesh grid to uniform grid which, when coupled
 with the multigrid solver, permits the coarse grid exact solve at
 higher resolution in parallel. This could significantly improve the
 scalability of the multigrid solver.

* Enhancement in the IO unit to permit splitting of a single checkpoint
 or plotfile. This feature is included to enable scalability of parallel
 file write on hundreds of thousands of processors.

* Fully supported implementations of Ionize, conductivity, viscosity
and diffusion.

* Reorganization of the Hydro and Driver units to better architect the
split versus un-split time integration.

* Enhancement in the Logfile unit to allow any processor in the simulation to
 be able to create and write into a private logfile. This feature is
 useful in gathering extra information from single/few processor
 failures when those failures do not occur on the master processor.


The FLASH3.1 release is available for download with a license agreement
at:

http://flash.uchicago.edu/website/download/

A stripped down version of FLASH3 that may be downloaded without a
license is also available at the same location. This version is
essentially the FLASH framework without any implementations.
Flash Center is also providing support for "add-ons" to the
code. Please see the section on "What's new in this release" in the
first chapter of the user's guide for details.


Additionally, the FLASH testing software FlashTest, which became
available with the alpha release, continues to be available for
download at:

http://flash.uchicago.edu/website/codesupport/

Many, but not all parts of FLASH3 are backwards-compatible with
FLASH2.  The Flash code group has written extensive documentation
detailing how to make the transition from FLASH2 to FLASH3 as smooth
as possible.  The user should look to:

http://flash.uchicago.edu/website/codesupport/

The website also contains other documentation including
a user's guide and a developer's section.  A new feature in FLASH3
documentation is the online description of the public interface
routines to various code units.


FLASH should be portable to most UNIX-like operating systems with a
python interpreter, Fortran 90 compiler,  C compiler and MPI library.
Please see the RELEASE-NOTES included in the FLASH source home
directory for a list of compilers, platforms and
library versions that are known to be compatible with FLASH.

FLASH output can be visualized using VisIt, a free interactive
visualization tool developed by Lawrence Livermore National
Laboratories under the ASCI initiative. VisIt is available from

http://flash.uchicago.edu/website/codesupport/visit, and
https://wci.llnl.gov/codes/visit

Development of the FLASH Code was funded by the DOE-supported
ASC/Alliance Center for Astrophysical Thermonuclear Flashes.  We
acknowledge support received from Lawrence Livermore National
Laboratory and the University of Chicago.

All publications resulting from the use of the FLASH Code must
acknowledge the ASC/Alliance Center for Astrophysical Thermonuclear
Flashes.  Addition of the following text to the paper acknowledgments
will be sufficient.

       "The software used in this work was in part developed by the
       DOE-supported ASC/Alliance Center for Astrophysical Thermonuclear
       Flashes at the University of Chicago."