TY - JOUR
T1 - Integrated predictive modelling of the effect of neutral gas puffing in ELMy H-mode plasmas
AU - Lönnroth, J.-S.
AU - Parail, V.V.
AU - Corrigan, G.
AU - Heading, D.
AU - Huysmans, G.T.A.
AU - Loarte, A.
AU - Saarelma, S.
AU - Saibene, G.
AU - Sharapov, S.
AU - Spence, J.
AU - EFDA-JET Workprogramme, contributors to the
PY - 2003/9/1
Y1 - 2003/9/1
N2 - The effect of neutral gas puffing in ELMy H-mode plasmas is studied
using integrated predictive transport modelling, which is needed because
of the strong link between the plasma core, the edge transport barrier
and the scrape-off layer. Self-consistent results are obtained by
coupling the one-dimensional core transport code JETTO with the
two-dimensional edge code EDGE2D. In addition, magnetohydrodynamic (MHD)
stability analysis is performed on the output of the transport
simulations. The results of the MHD stability analysis is used to adjust
MHD stability limits in the transport modelling, so that there is a
feedback loop between the transport codes and the MHD stability codes.
It is shown that strong gas puffing causes a sequence of causalities
involving edge density, collisionality, bootstrap current, total edge
current and magnetic shear, eventually triggering a transition from
second to first ideal (or resistive) n = infty ballooning stability.
Qualitatively, the transition from second to first ballooning stability
resembles the experimentally observed transition from type I to type III
ELMy H-mode with the accompanying increase in ELM frequency and
deterioration of plasma confinement.
AB - The effect of neutral gas puffing in ELMy H-mode plasmas is studied
using integrated predictive transport modelling, which is needed because
of the strong link between the plasma core, the edge transport barrier
and the scrape-off layer. Self-consistent results are obtained by
coupling the one-dimensional core transport code JETTO with the
two-dimensional edge code EDGE2D. In addition, magnetohydrodynamic (MHD)
stability analysis is performed on the output of the transport
simulations. The results of the MHD stability analysis is used to adjust
MHD stability limits in the transport modelling, so that there is a
feedback loop between the transport codes and the MHD stability codes.
It is shown that strong gas puffing causes a sequence of causalities
involving edge density, collisionality, bootstrap current, total edge
current and magnetic shear, eventually triggering a transition from
second to first ideal (or resistive) n = infty ballooning stability.
Qualitatively, the transition from second to first ballooning stability
resembles the experimentally observed transition from type I to type III
ELMy H-mode with the accompanying increase in ELM frequency and
deterioration of plasma confinement.
U2 - 10.1088/0741-3335/45/9/309
DO - 10.1088/0741-3335/45/9/309
M3 - Article
SN - 0741-3335
VL - 45
SP - 1689
EP - 1711
JO - Plasma Physics and Controlled Fusion
JF - Plasma Physics and Controlled Fusion
IS - 9
ER -