Investigation of the influence of divertor recycling on global plasma confinement in JET

0433627 - ÚFP 2015 JP eng A - Abstract
Tamain, P. - Joffrin, E. - Bufferand, H. - Brezinsek, S. - Beurskens, M. - Ciraolo, G. - Clever, M. - Giroud, C. - Dejarnac, Renaud - Drewelow, P. - Delabie, E. - Devaux, S. - Groth, M. - Hacquin, S. - Lipschutz, B. - Marsen, S. - Meigs, A. - Lomas, P. - Nunes, I. - Oberkofler, M. - Solano, E. - Wiesen, S. … Total 23 authors
Investigation of the influence of divertor recycling on global plasma confinement in JET.
21st International Conference on Plasma Surface Interactions 2014. Toki City: National Institute for Fusion Science, 2014. O33-O33.
[International Conference on Plasma Surface Interactions 2014/21./. 26.05.2014-30.05.2014, Kanazawa]
Institutional support: RVO:61389021
Keywords : Confinement * JET * recycling * ILW
Subject RIV: BL - Plasma and Gas Discharge Physics
http://psi2014.nifs.ac.jp/Files/Files/Abstracts/O33_Tamain_PSI2014.pdf

In this paper we investigate the possible influence of divertor recycling on the plasma confinement based on the analysis and modelling of dedicated experiments conducted in JET.A series of H-mode discharges was performed in which the divertor geometry was changed by moving the position of the strike points with respect to the pump duct entrances while keeping the main plasma’s shape as constant as possible.Low triangularity plasmas were considered in order to minimize the influence of main chamber recycling.At constant deuterium fuelling (puff from the private flux region) and power injection rates, changes of the confinement were observed.The H98 factor ranged from 0.7 to 0.95 with a maximum when the strike points were located in the corners, ie close to the pump duct entrances (corner configuration). Edge density and temperature profiles are impacted by the divertor configuration.The height of the density pedestal drops by a factor of 2 when the outboard pump duct entrance
Permanent Link: http://hdl.handle.net/11104/0237823