The role of the density profile in the ASDEX-Upgrade pedestal structure

被引：112

作者：

Dunne, M. G. ^{[1
]}

Potzel, S. ^{[1
]}

Reimold, F. ^{[2
]}

Wischmeier, M. ^{[1
]}

Wolfrum, E. ^{[1
]}

Frassinetti, L. ^{[3
]}

Beurskens, M. ^{[4
]}

Bilkova, P. ^{[5
]}

Cavedon, M. ^{[1
,6
]}

Fischer, R. ^{[1
]}

Kurzan, B. ^{[1
]}

Laggner, F. M. ^{[7
]}

McDermott, R. M. ^{[1
]}

Tardini, G. ^{[1
]}

Trier, E. ^{[1
]}

Viezzer, E. ^{[1
]}

Willensdorfer, M. ^{[1
]}

机构：

[1] Max Planck Inst Plasma Phys, D-85748 Garching, Germany

[2] Forschungszentrum Julich, D-52425 Julich, Germany

[3] KTH, Assoc EURATOM VR, Div Fus Plasma Phys, SE-10044 Stockholm, Sweden

[4] Max Planck Inst Plasma Phys, D-85748 Greifswald, Germany

[5] Inst Plasma Phys, Prague, Czech Republic

[6] Tech Univ Munich, Phys Dept E28, Garching, Germany

[7] TU Wien, Fus OAW, Inst Appl Phys, A-1040 Vienna, Austria

来源：

PLASMA PHYSICS AND CONTROLLED FUSION | 2017年 / 59卷 / 01期

关键词：

pedestal; scrape-off layer; peeling-balooning; prediction; ALCATOR C-MOD; TRANSPORT; TOKAMAK;

D O I：

10.1088/0741-3335/59/1/014017

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

Experimental evidence for the impact of a region of high density localised in the high-field side scrape-off layer (the HFSHD) on plasma confinement is shown in various dedicated experiments on ASDEX Upgrade (AUG). Increasing main ion fuelling is shown to increase the separatrix density and shift the density profile outwards. Predictive pedestal modelling of this shift indicates a 25% decrease in the attainable pedestal top pressure, which compares well with experimental observations in the gas scan. Since the HFSHD can be mitigated by applying nitrogen seeding, a combined scan in fuelling rate, heating power, and nitrogen seeding is presented. Significant increases in the achievable pedestal top pressure are observed with seeding, in particular at high heating powers, and are correlated with inward shifted density profiles and a reduction of the HFSHD and separatrix density. Interpretive linear stability analysis also confirms the impact of a radially shifted pressure profile on peeling-ballooning stability, with an inward shift allowing access to higher pressure gradients and pedestal widths.

引用

页数：8

共 30 条

[1] The effect of a metal wall on confinement in JET and ASDEX Upgrade [J].

Beurskens, M. N. A. ;

Schweinzer, J. ;

Angioni, C. ;

Burckhart, A. ;

Challis, C. D. ;

Chapman, I. ;

Fischer, R. ;

Flanagan, J. ;

Frassinetti, L. ;

Giroud, C. ;

Hobirk, J. ;

Joffrin, E. ;

Kallenbach, A. ;

Kempenaars, M. ;

Leyland, M. ;

Lomas, P. ;

Maddison, G. ;

Maslov, M. ;

McDermott, R. ;

Neu, R. ;

Nunes, I. ;

Osborne, T. ;

Ryter, F. ;

Saarelma, S. ;

Schneider, P. A. ;

Snyder, P. ;

Tardini, G. ;

Viezzer, E. ;

Wolfrum, E. .

PLASMA PHYSICS AND CONTROLLED FUSION, 2013, 55 (12)

[2] Comparison of hybrid and baseline ELMy H-mode confinement in JET with the carbon wall [J].

Beurskens, M. N. A. ;

Frassinetti, L. ;

Challis, C. ;

Osborne, T. ;

Snyder, P. B. ;

Alper, B. ;

Angioni, C. ;

Bourdelle, C. ;

Buratti, P. ;

Crisanti, F. ;

Giovannozzi, E. ;

Giroud, C. ;

Groebner, R. ;

Hobirk, J. ;

Jenkins, I. ;

Joffrin, E. ;

Leyland, M. J. ;

Lomas, P. ;

Mantica, P. ;

McDonald, D. ;

Nunes, I. ;

Rimini, F. ;

Saarelma, S. ;

Voitsekhovitch, I. ;

de Vries, P. ;

Zarzoso, D. .

NUCLEAR FUSION, 2013, 53 (01)

[3] Improved confinement in JET high β plasmas with an ITER-like wall [J].

Challis, C. D. ;

Garcia, J. ;

Beurskens, M. ;

Buratti, P. ;

Delabie, E. ;

Drewelow, P. ;

Frassinetti, L. ;

Giroud, C. ;

Hawkes, N. ;

Hobirk, J. ;

Joffrin, E. ;

Keeling, D. ;

King, D. B. ;

Maggi, C. F. ;

Mailloux, J. ;

Marchetto, C. ;

McDonald, D. ;

Nunes, I. ;

Pucella, G. ;

Saarelma, S. ;

Simpson, J. ;

Abhangi, M. ;

Abreu, P. ;

Aftanas, M. ;

Afzal, M. ;

Aggarwal, K. M. ;

Aho-Mantila, L. ;

Ahonen, E. ;

Aints, M. ;

Airila, M. ;

Albanese, R. ;

Alegre, D. ;

Alessi, E. ;

Aleynikov, P. ;

Alfier, A. ;

Alkseev, A. ;

Allan, P. ;

Almaviva, S. ;

Alonso, A. ;

Alper, B. ;

Alsworth, I. ;

Alves, D. ;

Ambrosino, G. ;

Ambrosino, R. ;

Amosov, V. ;

Andersson, F. ;

Andersson Sunden, E. ;

Angelone, M. ;

Anghel, A. ;

Anghel, M. .

NUCLEAR FUSION, 2015, 55 (05)

[4] Measurement of neoclassically predicted edge current density at ASDEX Upgrade [J].

Dunne, M. G. ;

McCarthy, P. J. ;

Wolfrum, E. ;

Fischer, R. ;

Giannone, L. ;

Burckhart, A. .

NUCLEAR FUSION, 2012, 52 (12)

[5]

Dunne M G, 2016, PLASMA PHYS CONTROL

[6] Progress at JET in integrating ITER-relevant core and edge plasmas within the constraints of an ITER-like wall [J].

Giroud, C. ;

Jachmich, S. ;

Jacquet, P. ;

Jarvinen, A. ;

Lerche, E. ;

Rimini, F. ;

Aho-Mantila, L. ;

Aiba, N. ;

Balboa, I. ;

Belo, P. ;

Angioni, C. ;

Beurskens, M. ;

Brezinsek, S. ;

Casson, F. J. ;

Coffey, I. ;

Cunningham, G. ;

Delabie, E. ;

Devaux, S. ;

Drewelow, P. ;

Frassinetti, L. ;

Figueiredo, A. ;

Huber, A. ;

Hillesheim, J. ;

Garzotti, L. ;

Goniche, M. ;

Groth, M. ;

Kim, Hyun-Tae ;

Leyland, M. ;

Lomas, P. ;

Maddison, G. ;

Marsen, S. ;

Matthews, G. ;

Meigs, A. ;

Menmuir, S. ;

Puetterich, T. ;

van Rooij, G. ;

Saarelma, S. ;

Stamp, M. ;

Urano, H. ;

Webster, A. .

PLASMA PHYSICS AND CONTROLLED FUSION, 2015, 57 (03)

[7] Edge profile stiffness and insensitivity of the density pedestal to neutral fuelling in Alcator C-Mod edge transport barriers [J].

Hughes, J. W. ;

LaBombard, B. ;

Terry, J. ;

Hubbard, A. ;

Lipschultz, B. .

NUCLEAR FUSION, 2007, 47 (08) :1057-1063

[8] Power requirements for superior H-mode confinement on Alcator C-Mod: experiments in support of ITER [J].

Hughes, J. W. ;

Loarte, A. ;

Reinke, M. L. ;

Terry, J. L. ;

Brunner, D. ;

Greenwald, M. ;

Hubbard, A. E. ;

LaBombard, B. ;

Lipschultz, B. ;

Ma, Y. ;

Wolfe, S. ;

Wukitch, S. J. .

NUCLEAR FUSION, 2011, 51 (08)

[9] Observations and empirical scalings of the high-confinement mode pedestal on Alcator C-Mod [J].

Hughes, JW ;

Mossessian, DA ;

Hubbard, AE ;

LaBombard, B ;

Marmar, ES .

PHYSICS OF PLASMAS, 2002, 9 (07) :3019-3030

[10] Impurity seeding for tokamak power exhaust: from present devices via ITER to DEMO [J].

Kallenbach, A. ;

Bernert, M. ;

Dux, R. ;

Casali, L. ;

Eich, T. ;

Giannone, L. ;

Herrmann, A. ;

McDermott, R. ;

Mlynek, A. ;

Mueller, H. W. ;

Reimold, F. ;

Schweinzer, J. ;

Sertoli, M. ;

Tardini, G. ;

Treutterer, W. ;

Viezzer, E. ;

Wenninger, R. ;

Wischmeier, M. .

PLASMA PHYSICS AND CONTROLLED FUSION, 2013, 55 (12)

← 1 2 3 →