SKM 2021 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

VA: Fachverband Vakuumphysik und Vakuumtechnik

VA 1: Rarefied gas flows and novel approaches for particle simulation

VA 1.1: Invited Talk

Monday, September 27, 2021, 10:00–10:30, H2

Deterministic and stochastic numerical approaches in Rarefied Gas Dynamics — •Stylianos Varoutis and Christos Tantos — Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany

During the last decade research in the field of rarefied gas dynamics has attracted a lot of attention. This refreshed interest is due to applications in the emerging field of nano- and micro-fluidics, as well as to the more traditional fields of vacuum technology and high altitude aerodynamics. Some of these applications may include important phenomena such as those related to polyatomic gases, chemical reactions, evaporation and condensation. The gas rarefaction is specified by the Knudsen number (Kn), which is defined as the ratio of the mean free path over a characteristic length of the problem. In general, when the flow is considered as far from local equilibrium, then the well-known Navier-Stokes equations are not valid anymore. In this case, two main numerical approaches can be implemented. The first approach is based on the kinetic theory of gases as expressed by the Boltzmann equation or its associated kinetic models, in which a deterministic numerical solution is performed. The second approach is the Direct Simulation Monte Carlo (DSMC) method. Within the above framework, the first part of this talk will be devoted to the presentation of the aforementioned numerical approaches, while the second part will be devoted to the presentation of illustrative examples, as for instance, the modelling of the particle exhaust of a nuclear fusion reactor and the numerical modelling of a cryopump.