[FLASH-USERS] FLASH4-beta released

[Klaus Weide]

The Flash Center is pleased to announce the beta release of the next
version of the FLASH code, version 4 beta. FLASH 4 beta includes
several new capabilities and resolves many bugs found in
previous releases up to 4-alpha.


The capabilities added since the alpha release are :

Capabilities added since the FLASH4-alpha include:

* 3T capabilities, support for non-Cartesian geometry, and support for
stationary rigid bodies in the unsplit hydrodynamics solver

* Upwind biased constrained transport (CT) scheme in the unsplit staggered mesh MHD solver

* Full corner transport upwind (CTU) algorithm in the unsplit hydro/MHD solver

* Multi-Temperature Multi-Material Multi-Table Eos 

* Ability to use cold opacities

* Several solvers have been threaded with two different degrees of parallelism. The
  block level threading  is coarser grained with one FLASH block being given to one 
  thread, there is a finer grain threading which threads performance critical loops. 
  Both modes use OpenMP.

* Laser drive is reconfigured and threaded.

* Several new HEDP simulation setups have been added.


Improvements to capabilities since the alpha release include:

* The HEDP capabilities have been more extensively tested, and are therefore more robust.

* Eos related runtime parameters are clearer.

* Several new shortcuts have been added to make it easier to use the
  new HEDP capabilities.

* The use of Gravitational acceleration is handled more accurately in Hydrodynamics.

* The interface with Hypre is more robust for diffusion.

* More boundary conditions in PFFT, some Poisson solvers can now handle
  combinations of different boundary conditions (DIRICHLET, NEUMANN, PERIODIC)
  on different domian boundaries.


Known Limitations:

* The new multipole solver is missing the ability to treat
  a non-zero minimal radius for spherical geometries, and the
  ability to specify a point mass contribution to the potential.

* Unsplit diffusion does not work in 3D.

* HYPRE needs to be installed to use Unsplit Diffusion, Unsplit diffusion
  uses hypre-2.7.0b (might not be backward compatible).

* Usage of HYPRE Split solver in FLASH4 is only for internal debugging purposes 
  and is not generally recommended for usage.

* Split diffusion has not been tested with PARAMESH.

* Some configurations of hydrodynamic test problems with Chombo grid
  show worse than expected mass and total energy conservation.  Please
  see the Chombo section in Hydro chapter of the FLASH user guide for
  details.

* We have experienced the following abort when running
  IsentropicVortex problem with Chombo Grid:
  "MayDay: TreeIntVectSet.cpp:1995: Assertion `bxNumPts != 0' failed. !!!"
  We are currently in contact with the Chombo team to resolve this
  issue.

* The absoft compiler produces erroneous results with optimization in
  gr_markRefineDerefine routine. The results are fine without
  optimization. There may be other files with similar behavior, but
  this is the only one we are aware of.

* The PG compiler fails to compile source files which contain OpenMP
  parallel regions that reference threadprivate data.  This happens in
  the threaded versions of the Multipole solver and the within block
  threaded version of split hydro.  A workaround is to remove
  "default(none)" from the OpenMP parallel region.

* The unsplit hydro solver has an issue with preserving symmetry in 
  non-fixed block size mode in UG.

* The ReineckeMeyer setup will not compile with the NAG compiler because
  of the presence of f77 like file used computing analytical solution

* We have been unable to use Hyper with OpenMPI in the FLASH code, the
  runs result in execution failures.

* The -index-reorder setup flag does not work in all the configurations.
  If you wish to use it please contact the FLASH team. 

* A longer list of changes is contained in the User's Guide in Section 1,
 What's New in This Release.

The release is available at:

http://flash.uchicago.edu/site/flashcode/

A stripped down version of FLASH3 that may be downloaded without a
license is also available at the same site.  This is essentially the
FLASH framework without any implementations. Additionally a collection
of mini-apps that represent the FLASH workload in many different
configurations is also availble under the general FLASH license
agreement. 


The Flash Center continues to provide support for "add-ons" to the
code.

Additionally, the FLASH testing software FlashTest, which became
available with the FLASH3, continues to be available for
download at:

http://flash.uchicago.edu/site/flashcode/

The code architecture and most interfaces of FLASH4 are compatible
with FLASH3.  Many, but not all parts are also backward compatible
with FLASH2.  The Flash Center 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/site/flashcode/user_support/

The website also contains other documentation including a User's Guide
and a developer's section.  A new feature from FLASH3 onward is the
online description of the public interface routines to various code
units. A new feature from the current release is a list of available
setup shortcuts.


Development of the FLASH Code was funded by the DOE-supported
ASC/Alliance Center for Astrophysical Thermonuclear Flashes,
and continues to be funded by DOE NNSA and NSF.  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 Flash Center for Computational Science.
 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 Flash Center for Computational Science
        at the University of Chicago."