Summary: Unsteady Turbomachinery Computations Using
Massively Parallel Platforms
Edwin van der Weide
, Georgi Kalitzin
, Jšorg Schlšuter
and Juan J. Alonso §
Stanford University, Stanford, CA 94305-4035
The CPU power offered by the latest generation of supercomputers is such that the
unsteady simulation of the full wheel of a compressor or turbine is now within reach. This
CPU power is mainly obtained by increasing the number of processors beyond several
thousands, e.g. the BlueGene/L computer of Lawrence Livermore National Laboratory
has approximately 130,000 processors. Consequently extreme care must be taken when
the simulation codes are ported to these platforms.
This paper discusses the computer scientific aspects of simulating unsteady turboma-
chinery flows on massively parallel systems when multi-block structured grids are used.
Load balance, parallel IO and search algorithms are addressed, especially for the case
where the number of processors is larger than the number of blocks, i.e. when blocks must
be split during runtime. Preliminary results for cases with more than 200 million nodes
running on 1,800 processors are presented.