ALCF Science 1 - Argonne National Laboratory

argonne leadership computing facility
Fusion
Global Simulation of Plasma Microturbulence at the
Petascale and Beyond
As the current global energy economy focuses on alternatives to fossil
fuels, there is increasing interest in nuclear fusion, the power source
of the sun and other stars, as an attractive possibility for meeting
the world’s growing energy needs. Properly understanding turbulent
transport losses, which demands the application of computational
resources at the extreme scale, is of the utmost importance for the
design and operation of future fusion devices, such as the multibillion
dollar international burning plasma experiment known as ITER
– a top priority investment in the Department of Energy’s Office of
Science. This Early Science project will achieve significantly improved
understanding of the influence of plasma size on confinement
properties in advanced tokamak systems such as ITER. This will
demand a systematic analysis of the underlying nonlinear turbulence
characteristics in magnetically confined tokamak plasmas that span the
range from current scale experiments, which exhibit an unfavorable
“Bohm-like” scaling with plasma size to the ITER scale plasma that
is expected to exhibit a more favorable “gyro-Bohm” scaling of
confinement. The “scientific discovery” aspect of such studies is that
while the simulation results can be validated against present-day
tokamaks, there are no existing devices today that are even one-
third of the radial dimension of
ITER. Accordingly, the role of
high physics fidelity predictive
simulations takes on an even more
important role—especially since
the expected improvement in
confinement for ITER-sized devices
cannot be experimentally validated
until after it is constructed and
operational. In dealing with this
challenge, researchers will deploy
GTC-P and GTS, which are highly
scalable particle-in-cell gyrokinetic
codes used for simulating
microturbulence-driven transport
in tokamaks.
Early Science Program
Allocation:
7.5 Million Hours
EARLY SCIENCE PROGRAM
31
Fully kinetic 3-D plasma microturbulence simulation in a tokamak fusion device of the
self-consistent electrostatic potential. The red and blue represent regions of positive and
negative potential respectively. Elongated structures in the toroidal direction follow the
magnetic field lines and is characteristic of the large anisotropy between the dynamics
parallel and perpendicular to the magnetic field observed in tokamak experiments.
Contact William Tang
Princeton Plasma Physics Laboratory | wtang@princeton.edu