M van Berkel, Gijs Lukas Derks, Lennard Ceelen, Thomas Bosman, B. Kool, T. Ravensbergen, J.T.W. Koenders, Chris Orrico, Loes Jansen, J. Roman, A. Perek, Himank Anand, Marco de Baar, M. Bernert, Dominik Brida, Ivo Samuel Carvalho, Basil P Duval, David Eldon, N. Fedorczak, O. Février, C. Galperti, S. Henderson, R.J.R. van Kampen, D. King, K. Kirov, O. Kudláček, M. Lennholm, Anthony Leonard, Nicola Lonigro, J. Lovell, Remy Nouailletas, Adam Parrot, L. Piron, Holger Reimerdes, B. Sieglin, Jelle Slief, H.J. Sun, Tuomas J J Tala, C. Theiler, D. Valcárcel, Kevin Verhaegh, C. Vincent, D. Weldon, Egbert Westerhof, T. Wijkamp, Sven Wiesen, the EUROfusion Tokamak Exploitation Team, the AUG Team, the DIII-D Team, the JET Team, the MAST-U Team, the TCV Team, the WEST Team
Abstract The understanding of the time-scales and associated transient behavior of fusion exhaust plasmas plays a crucial role in its dynamic modeling and its control. This work presents an overview of experimental investigations of the exhaust dynamics in TCV, MAST-U, ASDEX-Upgrade, WEST, DIII-D, and JET. From the presented experiments, a clear picture arises on properties of the exhaust dynamics across machines. Particularly, we observe that the scrape-off layer equilibrates on fast time-scales ( > 70 Hz) and that exhaust dynamics measured in response to gas valve modulations mostly behave smoothly and linearly, with similarities across devices, across scenarios (H-mode, L-mode), injected species, and injection locations. The measurements presented have formed the basis for systematic exhaust control on the considered devices. We now present this database for the essential validation of dynamic exhaust models for reactor design and control.