*Research Group Prof. Vornberger*

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Abstract: CFD with Adaptive FEM on Massively Parallel Systems

F. Lohmeyer, O. Vornberger

An explicit finite element scheme based on a two-step Taylor-Galerkin
algorithm allows the solution of the Euler and Navier-Stokes
equations for a wide variety of flow problems. To obtain useful results
for realistic problems, one has to use grids with an extremely
high density to obtain a good resolution of the interesting parts of a
given flow. Since these details are often limited to small regions
of the calculation domain, it is efficient to use unstructured grids to
reduce the number of elements and grid points. As such
calculations are very time consuming and inherently parallel, the use of
multiprocessor systems for this task seems to be a very natural
idea. A common approach for parallelization is the division of a given
grid, where the problem is the increasing complexity of this
task for growing processor numbers. Some general ideas for this kind of
parallelization and details of a Parix implementation for
Transputer networks are presented. To improve the quality of the
calculated solutions, an adaptive grid refinement procedure was
included. This extension leads to the need for a dynamic load balancing
for the parallel version. An effective strategy for this
task is presented and results for up to 1024 processors show the general
suitability of this approach for massively parallel systems.

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Strömungssimulation mit Hochleistungsrechnern

Reihe: Notes on Numerical Fluid Dynamics

Postscript (240 kB)