Three-Dimensional Simulation of Rarefied Plasma Flows Using a High Order Particle in Cell Method J. Neudorfer 4 , T. Stindl 1 , A. Stock 3 , R. Schneider 5 D. Petkow 1 , S. Roller 4 , C.-D. Munz 3 , and M. Auweter-Kurtz 2 1 Institut f¨ ur Raumfahrtsysteme, Abt. Raumtransporttechnologie, Universit¨at Stuttgart, Stuttgart, Germany, petkow@irs.uni-stuttgart.de 2 Steinbeis Transferzentrum Plasma- und Raumfahrttechnologie, Stuttgart, Germany, info@plasma-raumfahrt.de 3 Institut f¨ ur Aerodynamik und Gasdynamik, Universit¨at Stuttgart, Stuttgart, Germany, munz@iag.uni-stuttgart.de 4 German Research School for Simulation Sciences GmbH, Aachen, Germany, s.roller@grs-sim.de 5 Forschungszentrum Karlsruhe, Institut f¨ ur Hochleistungsimpuls- und Mikrowellentechnik, Karlsruhe, Germany, rudolf.schneider@ihm.fzk.de Summary. A three-dimensional Particle In Cell scheme for unstructured grids is presented. Since simulations of this kind require large computational resources, the solver was parallelized. The scalability of two parallel simulations is shown and an engineering application as well as two validation test cases for the scheme are presented. 1 Introduction A hybrid particle code currently under development for the fully kinetic mod- elling of the complete Boltzmann equation has been described previously [4]. In the present report, the focus is on the advancements regarding the Particle In Cell (PIC) part of the code. The newly incorporated high order discon- tinuous Galerkin (DG) approach for solving Maxwell’s equations is described in Sect. 2. Section 3 presents the charge and current deposition and interpo- lation methods. The performance of a newly implemented fourth-order low storage Runge-Kutta scheme to compute the particle movement is compared to that of the previously used second order Leap-Frog scheme in Sect. 4. In Sect. 5, the parallelization concept is described and results of scalability tests are shown. Finally, preliminary results of different simulation examples for the PIC solver are given in Sect. 6, followed by a summary and an outlook on future activities. W.E. Nagel et al. (eds.), High Performance Computing in Science and Engineering ’10, DOI 10.1007/978-3-642-15748-6 43, © Springer-Verlag Berlin Heidelberg 2011 593