Submitted by alexp on
Version 2.75 (build 2026-882-d4c63274) of the unstructured flow solver Arion is available for download.
Major features/changes/fixes in this release (relevant directive or option in parentheses):
Turbulence models
---------------------------------
Added the Spalart–Allmaras turbulence model, positive 2012 version.
(i.e. 'turbulent.sa')
Improved wall-function models for k-ω and Spalart–Allmaras models.
(i.e. 'nichols.wall.function')
Improved Laplacian calculation in SST-SAS.
(i.e. 'turbulent.kw.sst.sas')
Hybrid RANS/LES Turbulence models
---------------------------------
Added the IDDES RANS/LES hybrid turbulence model for both Spalart-Allmaras
(i.e. 'turbulent.sa.iddes') and k-w-SST
(i.e. 'turbulent.kw.sst.iddes')
IDDES models support the shear layer adapted length scale
(i.e. 'sla')
Added blended spatial differencing of the flow equations.
(i.e. '-hyb.didd.type', '-hyb.diss.min')
Frozen-chemistry simulations
----------------------------
Added an option for frozen-chemistry simulations with temperature-dependent heat-capacity ratio.
(i.e. 'mcg.frozen')
Ideal-gas system
----------------------------
Added AUSM.DV flux to the ideal-gas system.
(i.e. 'ausm.dv')
Time marching
----------------------------
Added 1st-order and limited blended 1st/2nd-order dual time schemes.
Note that the blended scheme is now the default. For backward compatibility, use the 2nd-order scheme.
(i.e. '-dual.time', '1st.order', '2nd.order', 'auto.order')
General additions
----------------------------
Added new line-search options.
(i.e. '-line.search flavor')
Wall distance calculation
-------------------------
New algorithm for wall distance is implemented, which also uses load balancing between ranks.
The algorithm has several flavors, and can, if the user request, verify the results against different flavor, or even against brute force search.
(i.e. '--solve -wall.distance')
Intermediate grid files
-----------------------
New common intermediate grid files folder in the "grid" folder.
Although Arion is backward compatible, it will overwrite a file if restarting to a similar folder, hence it is recommended, unless a must, to continue old version runs but to a new folder. The 'save' folder will be copied with a 'conversion' table (*.cnv) for restarting.
After the run, all the intermediate grid files in the grid folder can be removed (or kept to save time and compatibility for additional runs). During a run the 'lock' file is created to flag other processes that the grid is currently used, and while it exists, no other Arion process will commence reading the grid. In the event of a crash or user halting the process before Arion had a chance to remove the locking file, it is the responsibility of the user to remove it. A proper message is displayed to the user when Arion is run when the lock file is on.
Convergence criteria
------------------
Other convergence criteria can be included using: forces, moments and coefficients.
(i.e. '--converge', '-converge')
CGNS output file
----------------
Default is set to a single CGNS file containing all the simulation.
Added an option to use SIDS-standard variable names in the output.
Added an option to export only boundaries and/or walls to the plot output (CGNS only).
(i.e. '--plot -cgns')
Please refer to the command-line help for additional information.
Updated licenses will be available via regular distribution channels (upload/downoad facilities)
The relevant files are available for download from our website on the Arion downloads page.
