A systematic investigation of radiation collapse for disruption avoidance and prevention on JET tokamak

Rossi R.; Gelfusa M.; Craciunescu T.; Spolladore L.; Wyss I.; Peluso E.; Vega J.; Maggi C. F.; Mailloux J.; Maslov M.; Murari A.

doi:10.1063/5.0143193

Volume 8 Issue 4

Jul. 2023

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Rossi R., Gelfusa M., Craciunescu T., Spolladore L., Wyss I., Peluso E., Vega J., Maggi C. F., Mailloux J., Maslov M., Murari A., . A systematic investigation of radiation collapse for disruption avoidance and prevention on JET tokamak[J]. Matter and Radiation at Extremes, 2023, 8(4): 046903. doi: 10.1063/5.0143193

Citation:

Rossi R., Gelfusa M., Craciunescu T., Spolladore L., Wyss I., Peluso E., Vega J., Maggi C. F., Mailloux J., Maslov M., Murari A., . A systematic investigation of radiation collapse for disruption avoidance and prevention on JET tokamak[J]. Matter and Radiation at Extremes, 2023, 8(4): 046903. doi: 10.1063/5.0143193

Citation:

Rossi R., Gelfusa M., Craciunescu T., Spolladore L., Wyss I., Peluso E., Vega J., Maggi C. F., Mailloux J., Maslov M., Murari A., . A systematic investigation of radiation collapse for disruption avoidance and prevention on JET tokamak[J]. Matter and Radiation at Extremes, 2023, 8(4): 046903. doi: 10.1063/5.0143193

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A systematic investigation of radiation collapse for disruption avoidance and prevention on JET tokamak

doi: 10.1063/5.0143193

Rossi R.^1
,,
Gelfusa M.^{1
,
,
,},
Craciunescu T.^2
,,
Spolladore L.^1
,,
Wyss I.^1
,,
Peluso E.^1
,,
Vega J.^3
,,
Maggi C. F.⁴,
Mailloux J.⁴,
Maslov M.^4
,,
Murari A.^{5, 6
,},

1.
Department of Industrial Engineering, University of Rome “Tor Vergata,” via del Politecnico 1, Roma, Italy
2.
National Institute for Laser, Plasma and Radiation Physics, Magurele-Bucharest, Romania
3.
Laboratorio Nacional de Fusión, CIEMAT, Av. Complutense 40, 28040 Madrid, Spain
4.
UKAEA-CCFE, Culham Science Centre, Abingdon OX14 3DB, United Kingdom
5.
Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, 35127 Padova, Italy
6.
Istituto per la Scienza e la Tecnologia dei Plasmi, CNR, Padova, Italy
7.
EUROfusion Consortium, JET, Culham Science Centre, Abingdon OX14 3DB, United Kingdom

More Information

Corresponding author: a)Author to whom correspondence should be addressed: gelfusa@ing.uniroma2.it
Received Date: 2023-01-20
Accepted Date: 2023-05-07

Available Online: 2023-07-01

Publish Date: 2023-07-01

Abstract

Abstract

To produce fusion reactions efficiently, thermonuclear plasmas have to reach extremely high temperatures, which is incompatible with their coming into contact with material surfaces. Confinement of plasmas using magnetic fields has progressed significantly in the last years, particularly in the tokamak configuration. Unfortunately, all tokamak devices, and particularly metallic ones, are plagued by catastrophic events called disruptions. Many disruptions are preceded by anomalies in the radiation patterns, particularly in ITER-relevant scenarios. These specific forms of radiation emission either directly cause or reveal the approaching collapse of the configuration. Detecting the localization of these radiation anomalies in real time requires an innovative and specific elaboration of bolometric measurements, confirmed by visible cameras and the inversion of sophisticated tomographic algorithms. The information derived from these measurements can be interpreted in terms of local power balances, which suggest a new quantity, the radiated power divided by the plasma internal energy, to determine the criticality of the plasma state. Combined with robust indicators of the temperature profile shape, the identified anomalous radiation patterns allow determination of the sequence of macroscopic events leading to disruptions. A systematic analysis of JET campaigns at high power in deuterium, full tritium, and DT, for a total of almost 2000 discharges, proves the effectiveness of the approach. The warning times are such that, depending on the radiation anomaly and the available actuators, the control system of future devices is expected to provide enough notice to enable deployment of effective prevention and avoidance strategies.

Conflict of Interest
The authors have no conflicts to disclose.
Author Contributions
R. Rossi: Conceptualization (equal); Formal analysis (equal); Investigation (equal); Methodology (equal); Software (equal); Supervision (equal); Validation (equal); Visualization (equal). M. Gelfusa: Data curation (equal); Investigation (equal); Methodology (equal); Project administration (equal); Resources (equal); Supervision (equal); Writing – original draft (equal); Writing – review & editing (equal). T. Craciunescu: Formal analysis (equal); Investigation (equal); Writing – review & editing (equal). L. Spolladore: Data curation (equal); Investigation (equal); Supervision (equal); Visualization (equal); Writing – review & editing (equal). I. Wyss: Data curation (equal); Software (equal); Writing – review & editing (equal). E. Peluso: Data curation (equal); Investigation (equal); Software (equal); Writing – review & editing (equal). J. Vega: Investigation (equal); Project administration (equal); Writing – review & editing (equal). C. F. Maggi: Investigation (supporting); Project administration (supporting); Writing – review & editing (equal). J. Mailloux: Investigation (supporting); Project administration (supporting); Writing – review & editing (equal). M. Maslov: Investigation (supporting); Project administration (supporting); Writing – review & editing (equal). A. Murari: Conceptualization (equal); Formal analysis (equal); Investigation (equal); Methodology (equal); Supervision (equal); Writing – original draft (equal); Writing – review & editing (equal).
The data that support the findings of this study are available from EUROfusion Consortium. Restrictions apply to the availability of these data, which were used under license for this study. Data are available from the authors upon reasonable request and with the permission of EUROfusion Consortium.

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References(57)

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