Prof. Dr.-Ing.
Stefanos Fasoulas


Prof. Dr.-Ing. Sabine Klinkner

Prof. Dr. rer. nat. Alfred Krabbe

Prof. Fasoulas

Sheyla Fröhler-Valdez

Prof. Klinkner

Annegret Möller

Prof. Krabbe

Barbara Klett


Dr. Thomas Wegmann


Institut für Raumfahrtsysteme
Pfaffenwaldring 29
70569 Stuttgart

Tel. +49 711 685-69604
Fax +49 711 685-63596

Directly to


Particle Methods

Figure: Reentry of the Orion Crew Module with 7600 meters per second at an angle of attack of 26° and an altitude of 105 km

The Institute of Space Systems (IRS) and the Institute of Aerodynamics and Gasdynamics (IAG) cooperatively developed the particle simulation "PICLas", a flexible simulation suite for the computation of three-dimensional plasma flows. It is a coupled solver, which consists of a module for Particle in Cell (PIC) and module for Direct Simulation Monte Carlo (DSMC). The PIC module is responsible for the collisionless electromagnetic interactions and is complemented by the DSMC module, which calculates the collisions and chemical reactions of the particles. Both methods are being used in a variety of numerical applications. A different approach is taken for the numerical simulation of flows with large local density gradients. Here, the DSMC method is coupled with the new Low Diffusion (LD) method. LD is a special type of particle methods since it is based on particles but is in fact a continuum method.

Recent research results were summarized in a brochure: Download (PDF).


Spin-off - boltzplatz

A spin-off company "boltzplatz" is in preparation since mid of 2018, organised by alumni of the Institute of Space Systems and Institute of Aerodynamics and Gas Dynamics. The goal of the spin-off is the application of PICLas in other high-tech industries. More information and contact opportunities can be found at


Ortwein, P. et al. (2019). A particle localization algorithm on unstructured curvilinear polynomial meshes. Computer Physics Communications 235, 63-74. doi:10.1016/j.cpc.2018.09.024
Binder, T. et al. (2018). Load balancing strategies for the DSMC simulation of hypersonic flows using HPC. arXiv:1811.04742
Ortwein, P. et al. (2018). A Load Balance Strategy for Hybrid Particle-Mesh Methods, arXiv:1811.05152
Pfeiffer, M. (2018). Extending the particle ellipsoidal statistical Bhatnagar-Gross-Krook method to diatomic molecules including quantized vibrational energies. Physics of Fluids 30, 116103. doi:10.1063/1.5054961
Pfeiffer, M. (2018). Particle-based fluid dynamics: Comparison of different Bhatnagar-Gross-Krook models and the direct simulation Monte Carlo method for hypersonic flows. Physics of Fluids 30, 106106. doi:10.1063/1.5042016
Mirza, A., Nizenkov, P., Pfeiffer, M., and Fasoulas, S. (2017). Three-dimensional implementation of the Low Diffusion method for continuum flow simulations. Computer Physics Communications 220, 269-278. doi:10.1016/j.cpc.2017.07.018
Nizenkov, P., Pfeiffer, M., Mirza, A., and Fasoulas, S. (2017). Modeling of chemical reactions between polyatomic molecules for atmospheric entry simulations with direct simulation Monte Carlo. Physics of Fluids 29(7), 077104. doi:10.1063/1.4995468 Scilight Article
Pfeiffer, M. & Gorji, M.H. (2017). Adaptive particle-cell algorithm for Fokker-Planck based rarefied gas flow simulations. Computer Physics Communications 213, 1-8. doi:10.1016/j.cpc.2016.11.003
Nizenkov, P., Noeding, P., Konopka, M. and Fasoulas, S. (2016). Verification and validation of a parallel 3D direct simulation Monte Carlo solver for atmospheric entry applications. CEAS Space Journal 9(1), 127-137. doi:10.1007/s12567-016-0133-5
Pfeiffer, M., Nizenkov, P., Mirza, A., and Fasoulas, S. (2016). Direct simulation Monte Carlo modeling of relaxation processes in polyatomic gases. Physics of Fluids 28(2), 027103. doi:10.1063/1.4940989
Pfeiffer, M., Munz, C.-D. and Fasoulas, S. (2015). Hyperbolic divergence cleaning, the electrostatic limit, and potential boundary conditions for particle-in-cell codes. Journal of Computational Physics 294, 547–561. doi:10.1016/
Pfeiffer, M., Mirza, A., Munz, C.-D. and Fasoulas, S. (2015). Two statistical particle merge and split methods for Particle-In-Cell codes. Computer Physics Communications 191, 9–24. doi:10.1016/j.cpc.2015.01.010
Munz, C.-D., Auweter-Kurtz, M., Fasoulas, S. et al. (2014). Coupled Particle-In-Cell and Direct Simulation Monte Carlo method for simulating reactive plasma flows. Comptes Rendus Mécanique 342(10-11), 662–670.
Pfeiffer, M., Mirza, A. and Fasoulas, S. (2013). A grid-independent particle pairing strategy for DSMC. Journal of Computational Physics 246, 28–36. doi:10.1016/
Stindl, T., Neudorfer, J., Stock, A. et al. (2011). Comparison of coupling techniques in a high-order discontinuous Galerkin-based particle-in-cell solver. Journal of Physics D: Applied Physics 44, 194004. doi:10.1088/0022-3727/44/19/194004


31st International Symposium on Rarefied Gas Dynamics, 23-27 July, 2018, Glasgow, UK
  • Conference proceedings to be published soon
35th International Electric Propulsion Conference, 8-12 October, 2017, Atlanta, Georgia, USA
  • Binder, T., Leiter, H., Pfeiffer, M., Fasoulas, S. High-Fidelity Particle-In-Cell Simulations of Ion
    Thruster Optics.
8th Direct Simulation Monte Carlo Workshop, 27-30 August, 2017, Santa Fe, New Mexico, USA
  • Nizenkov, P., Zimmer, A.K., Elliot, J.O., Lyons, D.T., Fasoulas, S. Convective Heat Flux and Species Composition in the Wake of a Generic Capsule During an Aerobraking Maneuver at Titan
  • Pfeiffer, M., Copplestone, Munz, C.-D., Fasoulas, S. Simulation of Plasma Laser Interaction Using PIC-DSMC
  • Reschke, W., Pfeifer, M., Fasoulas, S. Modeling and Simulation of Catalytic Gas-Surface Interactions within DSMC.
14th International Planetary Probe Workshop, 12-16 June, 2017, The Hague, Netherlands
  • Nizenkov, P., Zimmer, A.K., Elliot, J.O., Lyons, D.T., Fasoulas, S. Simulation of the Flow During an Aerobraking Maneuver at Titan.
7th International Workshop on Radiation of High Temperature Gases, 21-25 November, 2016, Stuttgart
  • Pfeiffer, M. Nizenkov, P. Mirza, A., Fasoulas, S. First steps towards the coupling of the DSMC method with the radiation transport solver PARADE.
30th International Symposium on Rarefied Gas Dynamics, 10-15 July, 2016, Victoria, Canada
  • Binder, T. et al. Transmission Probabilities of Rarefied Flows in the Application of Atmosphere-Breathing Electric Propulsion. AIP Conference Proceedings 1786, 190011. doi:10.1063/1.4967689
  • Mirza, A., Nizenkov, P., Fasoulas, S. Flow Simulation around a 70-Degree Blunted Cone with Two Particle Methods in a Wide Knudsen Number Range. AIP Conference Proceedings 1786, 190001. doi:10.1063/1.4967679
  • Nizenkov, P. et al. Numerical Investigation of the Aerodynamics of the REX-Free Flyer in the Rarified Gas Regime. AIP Conference Proceedings 1786, 190005. doi:10.1063/1.4967683
  • Pfeiffer, M., Binder, T., Copplestone, S., Munz, C.-D. Comparison of Plasma Plume Expansion Simulations Using Fully Kinetic Electron Treatment and an Electron Fluid Model. AIP Conference Proceedings 1786, 130005. doi:10.1063/1.4967631
  • Reschke, W. et al. Recent Developments of DSMC within the Reactive Plasma Flow Solver PICLas. AIP Conference Proceedings 1786, 130003. doi:10.1063/1.4967629
7th Direct Simulation Monte Carlo Workshop, 12-19 September, 2015, Kauai, Hawaii, USA
  • Binder, T. et al. Application of PICLas to the Simulation of Electric Propulsion Systems
  • Nizenkov, P. et al. Application of PICLas to the Simulation of Atmospheric Entry Maneuvers
  • Fasoulas S., Mirza, A. et al. PICLas: A Highly Flexible Particle Code for the Simulation of Reactive Plasma Flows
8th European Symposium on Aerothermodynamics for Space Vehicles, 2-6 March, 2015, Lisbon, Portugal
  • Mirza, A., Mansk, R., Fasoulas, S. Implementation of Multitemperature Models in the Low Diffusion Particle Method for the Simulation of Internal Energy Nonequilibrium Effects in Continuum Flow Regions.
  • Nizenkov, P., Fasoulas, S. Validation of a Parallel 3D Direct Simulation Monte Carlo Solver for Atmospheric Entry Applications.