Release 1.5.1

Documentation

• Updated release and deploy developer guide section

Fixes

• Fixed crucial quadtree bug in 2D BGK

Release 1.5.0

The last major release for this year brings a ton of features and 2 major changes:

• The introduction of the parameter TrackingMethod replaces the parameters DoRefMapping and TriaTracking in the parameter files. The default tracking method is now TrackingMethod=triatracking, which is the appropriate method for most applications on regular linear meshes. This is equivalent to DoRefMapping=F and TriaTracking=T. The other available options refmapping and tracing are described in Section "4.1 Particle Tracking".
• The memory access has been optimized, leading to a change of the data format. To utilize state files produced by PICLas version < 1.5.0, a conversion of the state file is required. For this purpose, a script is provided in piclas/tools/flip_PartState/flip_PartState.py.

The complete list of features, improvements and fixes is available below.

Documentation

• Documentation of the background gas feature (see Section "4.7 Background Gas")
• Introduced a "Visualization & Output" chapter, which details the available output data in terms of particle information as well as gas flow, electromagnetic field and surface variables

Features

• Usage and calculation of a constant magnetic background field by coils and permanent magnets (see Section "4.6 Background Field")
• Detailed modelling of reactive surfaces (see Section "4.3.3 Surface Chemistry")
• Possibility to insert macroscopic bodies inside of the computational domain (e.g. to model droplets, see Section "4.8 Macroscopic Bodies")
• Deposition of charges on dielectric surfaces (see Section "4.3.4 Deposition of Charges on Dielectric Surfaces")
• Output of the particle data at the boundary (e.g. to visualize the impact energy at a boundary, see Section "5.1 Particle Data")
• Utilization of read-in cross sections for the collision probability with a background gas (see Section "4.7.1 Cross-section based collision probability")
• Linear temperature gradient as a variable wall temperature (see Section "4.3.1 Diffuse Wall")
• Consideration of dielectric materials in the simulation domain (see Section "4.2.3 Dielectric Materials")
• Modelling of diffusion through a wall possible with an adaptive inlet (Type=4) and surface flux (see Section "4.4.2.2 Adaptive Boundaries")
• Enabled the output of the mass flow rate by the surface flux emission (CalcMassflowRate = T)
• Variable relaxation probabilities based based on the models by Boyd & hang (see Section "4.7.6 Inelastic Collisions & Relaxation")

Improvements

• Introduced the TrackingMethod parameter to simplify the selection of the particle tracking method
• Removed and cleaned-up deposition methods routines
• Removed obsolete compiler and time discretization options
• Optimized memory access
• Updated default HDF5 version to 1.10.5: you may need to remove the compiler-specific folders within the "share" folder and recompile

Fixes

• Important bug fix for surface sampling communicators, which could cause a dead-lock for specific MPI domain decompositions
• Fix of multiple porous BC on a single boundary using regions
• Various smaller bug fixes

Release 1.4.0

Documentation

• Instructions for HEXPRESS usage

Features

• 2D/Axisymmetric DSMC & BGK simulations (see Section "2D/Axisymmetric Simulation" in Chapter "Features & Models")
• Variable time step for DSMC & BGK simulations (see Section "Variable Time Step" in Chapter "Features & Models")
• HDG is now compatible with mortar meshes

Improvements

• Added new read-in variable for specifying the length of the time stamp, e.g. "TimeStampLength=21"
• Enabled output of number density for reservoir simulations (per species, for complete domain) in PartAnalyze.csv ("CalcNumDens = TRUE")
• Added the cell-based output of new plasma parameters ("CalcPICCFLCondition" and "CalcMaxPartDisplacement")
• Added new preprocessor functions for skipping particles at interpolation, push and deposition

Fixes

• Several smaller fixes

Release 1.3.0

Documentation

• Added a guide for the simulation at bwUni cluster

Reggie

• Merged PIC regression test cases into a corresponding build folder

Features

• Support of non-conforming meshes (elements with hanging nodes) with TriaTracking for HOPR and HEXPRESS meshes
• Output of the coupled power can be enabled by "CalcCoupledPower=T"
• New "Linear Distribution Over Cell Interfaces" deposition method for PIC (for details see Chapter "Charge and Current Deposition")

Fixes

• Smaller bugfixes in TriaTracking
• Bugfixes when using a porous BC as a pump with a constant pumping speed
• Missing particle output in for Leapfrog time discretization with HDG

Release 1.2.0

Documentation

• Description of the particle emission through sampling, DSMC quality factors, surface flux, adaptive & porous BC, and gas-surface interaction modelling
• Description of the shape function as deposition method for PIC

Reggie

• Testing of inner BC, dielectric region and local shape function deposition elements
• Testing surface flux emission after check-in (ARM: DoRefMapping, Tracing & TriaTracking, TriaSurfaceFlux: only TriaTracking)

Features

• Modelling of near-continuum gas flows with the BGK and FP particle methods (see Section "Modelling of Continuum Gas Flows" in Chapter "Features & Models" of the user guide)
• 2D shape function (see Section "Particle-in-Cell" in Chapter "Features & Models" of the user guide)

Improvements

• Output of halo region in ElemData container of State.h5 file (through CalcHaloInfo=T parameter flag)
• Local deposition for the shape function at boundaries (through DoSFLocalDepoAtBounds=T parameter flag)

Fixes

• Missing use in Leapfrog time discretization method

Release 1.1.1

Features

• Skipping field update for the HDG solver for user-defined number of iterations
• Enabled output of inner boundary conditions (e.g. dielectric region with surface output)

Improvements

• Speed-up by skipping/cycle over neutral particles in deposition, interpolation and particle push due to electric/magnetic fields
• Flag to remove particles from dielectric regions
• Various regression test for relaxation and chemistry routines
• Output velocity vector as a vector (again), changed variable name "Pressure" to "ForcePerArea"
• QK Chemistry: included case for two possible reaction paths: dissociation and ionization (decision based on the analytic QK rate for each reaction)
• Output of current density for HDG solver

Fixes

• Treatment of non-linear polyatomic molecules during analyze and wall interaction
• Wrong call of chemistry routine from QK
• Various smaller bug fixes

Release 1.1.0

Documentation

• Added a user guide skeleton

Features

• Ioinization
  • Initial ionization with user-specified degree of ionization
  • Secondary electron emission to surface flux
  • Consideration of fully ionized species with Part-Species1-FullyIonized=T flag
  • Regression checks for QK ionization and recombination
• Validation for different types of magnetostatic analytic solution for time EOC verification
• Added compile option 'PICLAS_INTKIND8' in order to use KIND=8 integers when, e.g., running simulations with more than 2,147,483,648 particles
• Reworked existing adaptive boundary conditions and added new BCs (Constant mass flow and a porous BC to act as a pump)
• Post-processing: converter tool h5piclas2vtk enables visualization of DSMC output on a connected mesh

Fixes

• Restored original FillFlux routine by moving the InterFace decision to a separate routine. Additionally, the original Riemann() routine is now RiemannVacuum() routine
• Deallocate PPWCell, PPSCell, PPSCellEqui
• Changed the style guide rules: english language
• Bugfix DSMC sampling of electronic relaxation
• Hotfix memory allocation
• Empty dummy container for PartData in state file
• Bugfix in MCSoverMFP calculation