1
|
Murari A, Rossi R, Craciunescu T, Vega J, Gelfusa M. A control oriented strategy of disruption prediction to avoid the configuration collapse of tokamak reactors. Nat Commun 2024; 15:2424. [PMID: 38499564 PMCID: PMC10948913 DOI: 10.1038/s41467-024-46242-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 02/20/2024] [Indexed: 03/20/2024] Open
Abstract
The objective of thermonuclear fusion consists of producing electricity from the coalescence of light nuclei in high temperature plasmas. The most promising route to fusion envisages the confinement of such plasmas with magnetic fields, whose most studied configuration is the tokamak. Disruptions are catastrophic collapses affecting all tokamak devices and one of the main potential showstoppers on the route to a commercial reactor. In this work we report how, deploying innovative analysis methods on thousands of JET experiments covering the isotopic compositions from hydrogen to full tritium and including the major D-T campaign, the nature of the various forms of collapse is investigated in all phases of the discharges. An original approach to proximity detection has been developed, which allows determining both the probability of and the time interval remaining before an incoming disruption, with adaptive, from scratch, real time compatible techniques. The results indicate that physics based prediction and control tools can be developed, to deploy realistic strategies of disruption avoidance and prevention, meeting the requirements of the next generation of devices.
Collapse
Affiliation(s)
- Andrea Murari
- Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, Padova, Italy
- Istituto per la Scienza e la Tecnologia dei Plasmi, CNR, Padova, Italy
| | - Riccardo Rossi
- University of Rome "Tor Vergata", via del Politecnico 1, Roma, Italy
| | - Teddy Craciunescu
- National Institute for Laser, Plasma and Radiation Physics, Magurele-Bucharest, Romania
| | - Jesús Vega
- Laboratorio Nacional de Fusión, CIEMAT. Av. Complutense 40, Madrid, Spain
| | - Michela Gelfusa
- University of Rome "Tor Vergata", via del Politecnico 1, Roma, Italy.
| |
Collapse
|
2
|
Giacomin M, Pau A, Ricci P, Sauter O, Eich T. First-Principles Density Limit Scaling in Tokamaks Based on Edge Turbulent Transport and Implications for ITER. Phys Rev Lett 2022; 128:185003. [PMID: 35594105 DOI: 10.1103/physrevlett.128.185003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 02/10/2022] [Accepted: 04/08/2022] [Indexed: 06/15/2023]
Abstract
A first-principles scaling law, based on turbulent transport considerations, and a multimachine database of density limit discharges from the ASDEX Upgrade, JET, and TCV tokamaks, show that the increase of the boundary turbulent transport with the plasma collisionality sets the maximum density achievable in tokamaks. This scaling law shows a strong dependence on the heating power, therefore predicting for ITER a significantly larger safety margin than the Greenwald empirical scaling [Greenwald et al., Nucl. Fusion, 28, 2199 (1988)NUFUAU0029-551510.1088/0029-5515/28/12/009] in case of unintentional high-to-low confinement transition.
Collapse
Affiliation(s)
- M Giacomin
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - A Pau
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - P Ricci
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - O Sauter
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - T Eich
- Max-Planck-Institute for Plasma Physics, Boltzmannstrasse 2, D-85748 Garching, Germany
| |
Collapse
|
3
|
Bruschi A, Bin W, Cirant S, Granucci G, Mantovani S, Moro A, Nowak S. A New Launcher for Real-Time ECRH Experiments on FTU. Fusion Science and Technology 2017. [DOI: 10.13182/fst09-27] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- A. Bruschi
- Istituto di Fisica del Plasma CNR-EURATOM-ENEA Association, via Cozzi 53, 20125 Milano, Italy
| | - W. Bin
- Istituto di Fisica del Plasma CNR-EURATOM-ENEA Association, via Cozzi 53, 20125 Milano, Italy
| | - S. Cirant
- Istituto di Fisica del Plasma CNR-EURATOM-ENEA Association, via Cozzi 53, 20125 Milano, Italy
| | - G. Granucci
- Istituto di Fisica del Plasma CNR-EURATOM-ENEA Association, via Cozzi 53, 20125 Milano, Italy
| | - S. Mantovani
- Association EURATOM-ENEA sulla Fusione, CR Frascati, C.P. 65-00044 Frascati, Roma, Italy
| | - A. Moro
- Istituto di Fisica del Plasma CNR-EURATOM-ENEA Association, via Cozzi 53, 20125 Milano, Italy
| | - S. Nowak
- Istituto di Fisica del Plasma CNR-EURATOM-ENEA Association, via Cozzi 53, 20125 Milano, Italy
| |
Collapse
|
5
|
Volpe FA, Hyatt A, La Haye RJ, Lanctot MJ, Lohr J, Prater R, Strait EJ, Welander A. Avoiding Tokamak Disruptions by Applying Static Magnetic Fields That Align Locked Modes with Stabilizing Wave-Driven Currents. Phys Rev Lett 2015; 115:175002. [PMID: 26551119 DOI: 10.1103/physrevlett.115.175002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Indexed: 06/05/2023]
Abstract
Nonrotating ("locked") magnetic islands often lead to complete losses of confinement in tokamak plasmas, called major disruptions. Here locked islands were suppressed for the first time, by a combination of applied three-dimensional magnetic fields and injected millimeter waves. The applied fields were used to control the phase of locking and so align the island O point with the region where the injected waves generated noninductive currents. This resulted in stabilization of the locked island, disruption avoidance, recovery of high confinement, and high pressure, in accordance with the expected dependencies upon wave power and relative phase between the O point and driven current.
Collapse
Affiliation(s)
- F A Volpe
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA
| | - A Hyatt
- General Atomics, P.O. Box 85608, San Diego, California 92121, USA
| | - R J La Haye
- General Atomics, P.O. Box 85608, San Diego, California 92121, USA
| | - M J Lanctot
- General Atomics, P.O. Box 85608, San Diego, California 92121, USA
| | - J Lohr
- General Atomics, P.O. Box 85608, San Diego, California 92121, USA
| | - R Prater
- General Atomics, P.O. Box 85608, San Diego, California 92121, USA
| | - E J Strait
- General Atomics, P.O. Box 85608, San Diego, California 92121, USA
| | - A Welander
- General Atomics, P.O. Box 85608, San Diego, California 92121, USA
| |
Collapse
|
6
|
Zhang YP, Liu Y, Luo XB, Isobe M, Yuan GL, Liu YQ, Hua Y, Song XY, Yang JW, Li X, Chen W, Li Y, Yan LW, Song XM, Yang QW, Duan XR. Development of the scintillator-based probe for fast-ion losses in the HL-2A tokamak. Rev Sci Instrum 2014; 85:053502. [PMID: 24880364 DOI: 10.1063/1.4872385] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A new scintillator-based lost fast-ion probe (SLIP) has been developed and operated in the HL-2A tokamak [L. W. Yan, X. R. Duan, X. T. Ding, J. Q. Dong, Q. W. Yang, Yi Liu, X. L. Zou, D. Q. Liu, W. M. Xuan, L. Y. Chen, J. Rao, X. M. Song, Y. Huang, W. C. Mao, Q. M. Wang, Q. Li, Z. Cao, B. Li, J. Y. Cao, G. J. Lei, J. H. Zhang, X. D. Li, W. Chen, J. Chen, C. H. Cui, Z. Y. Cui, Z. C. Deng, Y. B. Dong, B. B. Feng, Q. D. Gao, X. Y. Han, W. Y. Hong, M. Huang, X. Q. Ji, Z. H. Kang, D. F. Kong, T. Lan, G. S. Li, H. J. Li, Qing Li, W. Li, Y. G. Li, A. D. Liu, Z. T. Liu, C. W. Luo, X. H. Mao, Y. D. Pan, J. F. Peng, Z. B. Shi, S. D. Song, X. Y. Song, H. J. Sun, A. K. Wang, M. X. Wang, Y. Q. Wang, W. W. Xiao, Y. F. Xie, L. H. Yao, D. L. Yu, B. S. Yuan, K. J. Zhao, G. W. Zhong, J. Zhou, J. C. Yan, C. X. Yu, C. H. Pan, Y. Liu, and the HL-2A Team, Nucl. Fusion 51, 094016 (2011)] to measure the losses of neutral beam ions. The design of the probe is based on the concept of the α-particle detectors on Tokamak Fusion Test Reactor (TFTR) using scintillator plates. The probe is capable of traveling across an equatorial plane port and sweeping the aperture angle rotationally with respect to the axis of the probe shaft by two step motors, in order to optimize the radial position and the collimator angle. The energy and the pitch angle of the lost fast ions can be simultaneously measured if the two-dimensional image of scintillation light intensity due to the impact of the lost fast ions is detected. Measurements of the fast-ion losses using the probe have been performed during HL-2A neutral beam injection discharges. The clear experimental evidence of enhanced losses of beam ions during disruptions has been obtained by means of the SLIP system. A detailed description of the probe system and the first experimental results are reported.
Collapse
Affiliation(s)
- Y P Zhang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Yi Liu
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X B Luo
- Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610041, China
| | - M Isobe
- National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5259, Japan
| | - G L Yuan
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Y Q Liu
- Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610041, China
| | - Y Hua
- Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610041, China
| | - X Y Song
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - J W Yang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X Li
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - W Chen
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Y Li
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - L W Yan
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X M Song
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Q W Yang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X R Duan
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| |
Collapse
|
7
|
Gates DA, Delgado-Aparicio L. Origin of tokamak density limit scalings. Phys Rev Lett 2012; 108:165004. [PMID: 22680727 DOI: 10.1103/physrevlett.108.165004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Indexed: 06/01/2023]
Abstract
The onset criterion for radiation driven islands [P. H. Rebut and M. Hugon, Plasma Physics and Controlled Nuclear Fusion Research 1984: Proc. 10th Int. Conf. London, 1984, (IAEA, Vienna, 1985), Vol. 2] in combination with a simple cylindrical model of tokamak current channel behavior is consistent with the empirical scaling of the tokamak density limit [M. Greenwald, Nucl. Fusion 28, 2199 (1988)]. Many other unexplained phenomena at the density limit are consistent with this novel physics mechanism.
Collapse
Affiliation(s)
- D A Gates
- Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, New Jersey 08543, USA
| | | |
Collapse
|
8
|
Li E, Hu L, Ling B, Liu Y, Ti A, Chen K, Shen B, Gao X. Electron cyclotron emission reconstruction image and m/n = 3/2 mode in HT-7 tokamak. Rev Sci Instrum 2010; 81:073506. [PMID: 20687721 DOI: 10.1063/1.3459882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Electron cyclotron emission reconstruction image has been used for flux surface reconstruction. The reconstruction image is based on plasma rigid rotation which is obtained from Mirnov diagnostic. From the reconstructed two-dimensional flux surface, the classical m/n = 3/2 mode is visualized, which is of similar spatial structure as neoclassical 3/2 mode observed in some other tokamaks [B. Esposito et al., Phys. Rev. Lett. 100, 045006 (2008)].
Collapse
Affiliation(s)
- Erzhong Li
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China.
| | | | | | | | | | | | | | | |
Collapse
|