Speaker
Prof.
Paolo Ricci
(CRPP, EPFL)
Description
The methodology used to assess the reliability of numerical
simulation codes
constitutes the Verification and Validation (V&V) procedure.
V&V is composed by two
separate tasks: the verification process, which is a
mathematical issue targeted to
assess that the physical model is correctly solved by the
numerical code, and the
validation, which determines the consistency of the code
results, and therefore of the
physical model, with experimental data. In the present work,
a rigorous V&V
procedure is presented and applied showing, through a
practical example, how it can
advance our physics understanding of plasma turbulence.
Bridging the gap between
plasma physics and other scientific domains, in particular the
computational fluid
dynamics community, a rigorous methodology for the
verification of a plasma
simulation code is presented, based on the method of
manufactured solution and
Roache's grid converge index. This methodology assesses
that the model equations
are correctly solved, within the order of accuracy of the
numerical scheme, and
provides a rigorous estimate of the uncertainty affecting the
numerical results. Two-
dimensional and three-dimensional verified simulations of the
basic plasma physics
experiment TORPEX are then performed, and rigorously
validated against the
experimental data. The validation procedure allows progress
in the understanding of
the turbulent dynamics in TORPEX, by pinpointing the
presence of a turbulent regime
transition, due to the competition between the resistive and
ideal interchange
instabilities.
Primary author
Prof.
Paolo Ricci
(CRPP, EPFL)
Co-authors
Prof.
Ambrogio Fasoli
(CRPP, EPFL)
Dr
Christian Theiler
(CRPP, EPFL)
Mr
Fabio Riva
(CRPP, EPFL)
Dr
Federico Halpern
(CRPP, EPFL)
Dr
Ivo Furno
(CRPP, EPFL)
Dr
Joaquim Loizu
(IPP, MPI)
