User Guide

PICLas comes with a vast variety of models and methods. Originally being centered around Particle-in-Cell (PIC) and Direct Simulation Monte Carlo (DSMC) methods, PICLas has been extended to other particle-based methods, namely Bhatnagar-Gross-Krook (BGK) and Fokker-Planck (FP) models. Each of these models, some of which can be combined, offer distinctive features such as

• Coupled Particle-in-Cell with Direct Simulation Monte Carlo methods

• Particle-based Bhatnagar-Gross-Krook (Ellipsoidal Statistical, Shakov, Unified) and Fokker-Planck (Cubic, Ellipsoidal Statistical) models for continuum gas flows

• Arbitrary order nodal polynomial tensor product basis using Gauss or Gauss Lobatto collocation points for electrostatic and electromagnetic solvers

• Matching high order curved mesh generation from external mesh formats (CGNS, GMSH) or simple analytic blocks via the open source preprocessor HOPR [1]

• Non-conforming interfaces [2] based on the mortar approach [3, 4] (electromagnetic solver)

• Non-reflecting boundary conditions via CFS-PMLs [5] (electromagnetic solver)

• Automatic domain decomposition for parallel simulations based on a space filling curve

• High order low-storage explicit Runge-Kutta time integration [6]

• I/O using the HDF5 library optimized for massively parallel jobs

Table of Contents

• 1. Installation
• 2. Mesh Generation
• 3. Workflow
• 4. Features & Models
• 5. Visualization & Output
• 6. Tools
• 7. Tutorials
• 8. Cluster Guidelines
• 9. Appendix

This user guide is organized to both guide the first steps as well as provide a complete overview of the simulation code’s features from a user and a developer point of view.

• Chapter Installation contains step by step instructions from obtaining the source code up to running a first simulation and visualizing the simulation results. In addition, it provides an overview of the whole simulation framework and the currently implemented features.

• Chapter Mesh Generation describes the preprocessing step of creating mesh files via the in-house tool HOPR that also handles mesh formats created with external mesh generators

• Chapter Workflow outlines the workflow and the visualization of results produced with PICLas.

• Chapter Features & Models shall serve as a reference for the models and features implemented in PICLas.

• Chapter Visualization & Output presents the options and parameters for the output of particle data, field and flow variables.

• Chapter Tools lists tools within the PICLas repository, including the post-processing tools.

• Simulation tutorials are contained in Chapter Tutorials.

• Cluster-specific user guidelines are given in Chapter Cluster Guidelines.