Doctoral seminar

CFD++ - Multi-Scale methods for Real Gas Applications, Aero Acoustics, Plasma Flows and Medical Physics in the face of HPC:
Multi-Scale simulations became more and more important over the last years. The simulation techniques in the individual fields are mature, while the step closer to reality often means to include more than one regime into a coupled application. With respect to code development and parallelization, this leads to more modular environment, encapsulating the information about the given regime while allowing for interaction between the scales and physical phenomena.
We consider aero acoustic applications, coupling the sound generation in viscous flow around complex geometries with sound propagation in the far field, where inviscid, linearized Euler equations are appropriate, but a discretization has to take into account the long distances as well as low dispersion requirements. We consider plasma flows where a particle-in-cell scheme is applied for the low density flow to couple continuous electromagnetic fields with discrete particles. We consider medical physics applications which consists of a Lattice Boltzmann simulation with a non-Newtonian model for the bulk flow, and a closely coupled suspension code for a detailed modeling of red blood cells near the wall boundaries.
To deal with applications described here, we develop a coupling framework to allow for different discretization schemes like Finite Volume on structured meshes, Discontinuous Galerkin on unstructured grids or Lattice Boltzmann schemes in sparse implementations. The scheme is a heterogenous two-stage domain decomposition, allowing for the coupling of different discretizations, time steps, and even different physical equation systems. It also includes the possibility to map the individual modules to the best suited computing hardware even on different machines. We will describe the implications and consequences to parallelization and simulation performance.
Additionally, the talk will consider some aspects of supercomputing from the users point of view. Experiences were achieved in the past years as members of Deisa, Prace and HPC Europa.

Speaker: Prof. Dr.-Ing. Sabine Roller, Applied Supercomputing in Engineering, German Research School for Simulation Sciences, RWTH Aachen University

Date: Monday, June 7, 2010

Time: 16:15

Location: Lecture Room 001, Schinkelstr. 2a, German Research School for Simulation Sciences, 52062 Aachen