Release 2.0.0

The major version increase to 2.0.0 comes with the introduction of shared memory windows following the MPI3.0 standard into PICLas. The particle communication has been moved from the inter-core to the inter-node level. This development responds to the current trend in high-performance computing of many-core CPUs.

Features

• Shared memory implementation following the MPI3.0 standard. Details on the implementation can be found within the developer guide (piclas/doc/developerguide/)
• Radiative equilibrium boundary condition: Calculation of the temperature based on the incoming heat flux
• New electronic relaxation modelling, where each simulation particle carries an electronic energy distribution function
• Boundary conditions of rotating systems: rotational periodic boundary condition and rotating wall
• Simple ambipolar diffusion model: electrons are "attached" to the ionic species (and thus move with their velocity), but have a separate velocity vector, which is utilized for relaxation and chemical processes
• Cross-section based chemistry modelling and extension to four products (e.g. allowing dissociative ionization reactions and other reaction types)

Improvements

• Possibility to individually select the reactions, whose backward reactions shall be treated with the equilibrium constant
• The reaction type is now determined automatically and a reaction model (e.g. "TCE", "QK" or "XSec") must be selected
• Refactoring of several routines

Release 1.9.0

Documentation

• Compilation on Hawk (HPE Apollo @ HLRS)
• Installation guide for CentOS 7

Features

• Multi-species ESBGK modelling (see Section "4.9.2 Bhatnagar-Gross-Krook Collision Operator")
• Python script to create a cylindrical mesh with HOPR (in piclas/tools/createCylinderHOPR)

Fixes

• Removed "read*" occurrences from code

Release 1.8.0

With the introduction of the Variable Soft Sphere model in the current release, the input parameters of the collision model have changed:

! Old: Part-Species1-VHSReferenceTemp = 273
Part-Species1-Tref = 273 
! Old: Part-Species1-VHSReferenceDiam = 4E-10
Part-Species1-dref = 4E-10
! Old: Part-Species1-omegaVHS = 0.24
Part-Species1-omega = 0.24

The code will abort, when using the old parameters. More details can be found in Section "4.7.4 Species Definition" and "4.7.5 Pairing & Collision Modelling".

Features

• 1D Simulation (e.g. for shock-tube simulations, see Section "4.7.3 Symmetric Simulations")
• Variable Soft Sphere (VSS) collision model and support for collision and species-specific VHS/VSS parameters (see Section "4.7.5 Pairing & Collision Modelling")

Improvements

• Display the elapsed CPU time in std.out when ABORT is called

Fixes

• Bugfix in photo-ionization: third particle did not receive a velocity change
• Fixed evaluation of BGField in EvaluateFieldAtPhysPos and EvaluateFieldAtRefPos

Release 1.7.0

Features

• Modelling of photo-ionization processes by photon impact with a background gas and a surface

Improvements

• Improved reproducibility of simulation results by including the compile flags in the "userblock" as well as the git commit hash (next to the version number) in standard output
• Increased performance of the HDG solver:
  • Fixed the load balance weighting method
  • Restart without recomputing the HDG lambda solution

Fixes

• Bugfix in treatment of identical particles in the rotational 2D symmetry case with radial weighting

Release 1.6.4

Fixes

• Fixed compilation (make) and installation (make install) for shared libs for cmake versions <3.14

Release 1.6.3

Improvements

• Added calculation of field and particle ElemTime separately and added output to ElemTimeStatistics.csv
• Output error norms for HDG to FieldAnalyze.csv
• Updated tools for determining the electric current from PartStateBoundary files
• Extended tool for merging of state files (DSMCState, DSMCSurfState, PartStateBoundary, TimeAvg, etc.) for post-processing

Fixes

• Fixed the compilation under GCC 9/10 (new default in Ubuntu 20.04)
• Fixed compilation with fixed polynomial degree
• Missing load balance timer in background gas particle insertion
• Missing load balance timer in HDG
• Fixed installation target for the shared library

Release 1.6.2

Improvements

• Included electronic energy relaxation at the wall and added a regression test for energy accommodation at the wall

Fixes

• Fix of compilation with the Intel compiler and Intel MKL

Release 1.6.1

Features

• Output of lost particles during tracking and restart in a single file for debugging (see Section "5.1 Particle Data")

Improvements

• Clean-up and speed-up of nightly regression tests
• Refactoring of the DSMC main routine and particle pairing routines

Fixes

• Avoid overflows in exponential functions in DSMC chemistry

Release 1.6.0

Features

• Added new SEE-I model for Ar+ bombarding different types of metal
• Background gas: Extension to polyatomic molecules and gas mixtures
• Boris-Leapfrog time integration for PIC (Poisson)
• Delete specified products after a chemical reaction

Improvements

• Regression tests for MCC and background gas routines
• h5piclas2vtk: Automatic output of DG_Source if it is available

Fixes

• Fix of inner boundaries in combination with an open boundary
• Fix in h5piclas2vtk for VisuParticles=T
• Fix particle time integration analytical initial conditions
• Fix in the nearest neighbour search in DSMC

Release 1.5.2

Documentation

• Added troubleshooting for access to Gitlab with port-forwarding

Features

• Implemented diatomic species with the cubic Fokker-Planck method

Improvements

• Added a "Time remaining" status line as console output (enabled by "doPrintStatusLine=T")

Fixes

• Fixed a bug in the FinalizeDSMC routine
• Fixed a bug in the h5piclas2vtk converter tool