TY - JOUR
T1 - Stationarity of I-mode operation and I-mode divertor heat fluxes on the ASDEX Upgrade tokamak
AU - the ASDEX Upgrade Team
AU - the EUROfusion MST1 Team
AU - Happel, T.
AU - Griener, M.
AU - Silvagni, D.
AU - Freethy, S. J.
AU - Hennequin, P.
AU - Janky, F.
AU - Manz, P.
AU - Prisiazhniuk, D.
AU - Ryter, F.
AU - Bernert, M.
AU - Brida, D.
AU - Eich, T.
AU - Faitsch, M.
AU - Gil, L.
AU - Guimarais, L.
AU - Merle, A.
AU - Nille, D.
AU - Pinzón, J.
AU - Sieglin, B.
AU - Stroth, U.
AU - Viezzer, E.
N1 - Publisher Copyright:
© 2018 The Authors
PY - 2019/1
Y1 - 2019/1
N2 - Recent I-mode investigations from the ASDEX Upgrade tokamak are reported. It is shown that neutral-beam-injection heated I-modes can be stationary, which is important in terms of extrapolability towards future fusion devices. Furthermore, detailed studies on the weakly coherent mode are reported. In particular, experimental observations point towards its existence in L-mode, before I-mode starts. Moreover, its impact on density and temperature fluctuations is evaluated. Studies of stationary divertor heat fluxes show that in I-mode, the upstream power fall-off length is between those observed in L-mode and H-mode, and it is connected to the scrape-off layer temperature fall-off length. Moreover, analysis of transient divertor heat loads shows that intermittent turbulent events, observed in the confinement region and linked to the weakly coherent mode, are responsible for a significant part of divertor heat loads.
AB - Recent I-mode investigations from the ASDEX Upgrade tokamak are reported. It is shown that neutral-beam-injection heated I-modes can be stationary, which is important in terms of extrapolability towards future fusion devices. Furthermore, detailed studies on the weakly coherent mode are reported. In particular, experimental observations point towards its existence in L-mode, before I-mode starts. Moreover, its impact on density and temperature fluctuations is evaluated. Studies of stationary divertor heat fluxes show that in I-mode, the upstream power fall-off length is between those observed in L-mode and H-mode, and it is connected to the scrape-off layer temperature fall-off length. Moreover, analysis of transient divertor heat loads shows that intermittent turbulent events, observed in the confinement region and linked to the weakly coherent mode, are responsible for a significant part of divertor heat loads.
UR - http://www.scopus.com/inward/record.url?scp=85059032603&partnerID=8YFLogxK
U2 - 10.1016/j.nme.2018.12.022
DO - 10.1016/j.nme.2018.12.022
M3 - Article
AN - SCOPUS:85059032603
SN - 2352-1791
VL - 18
SP - 159
EP - 165
JO - Nuclear Materials and Energy
JF - Nuclear Materials and Energy
ER -