Academic Journal
Disruption event characterization and forecasting in tokamaks
| العنوان: | Disruption event characterization and forecasting in tokamaks |
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| المؤلفون: | Sabbagh, S. A., Berkery, J. W., Park, Y. S., Butt, J., Riquezes, J. D., Bak, J. G., Bell, R. E., Delgado-Aparicio, L., Gerhardt, S. P., Ham, C. J., Hollocombe, J., Lee, J. W., Kim, J., Kirk, A., Ko, J., Ko, W. H., Kogan, L., LeBlanc, B. P., Lee, J. H., Thornton, A., Yoon, S. W. |
| المساهمون: | U.S. Department of Energy, Korea Institute of Fusion Energy, EPSRC Energy Programme |
| المصدر: | Physics of Plasmas ; volume 30, issue 3 ; ISSN 1070-664X 1089-7674 |
| بيانات النشر: | AIP Publishing |
| سنة النشر: | 2023 |
| الوصف: | Disruption prediction and avoidance is a critical need for next-step tokamaks, such as ITER. Disruption Event Characterization and Forecasting (DECAF) research fully automates analysis of tokamak data to determine chains of events that lead to disruptions and to forecast their evolution allowing sufficient time for mitigation or complete avoidance of the disruption. Disruption event chains related to local rotating or global magnetohydrodynamic (MHD) modes and vertical instability are examined with warnings issued for many off-normal physics events, including density limits, plasma dynamics, confinement transitions, and profile variations. Along with Greenwald density limit evaluation, a local radiative island power balance theory is evaluated and compared to the observation of island growth. Automated decomposition and analysis of rotating tearing modes produce physical event chains leading to disruptions. A total MHD state warning model comprised of 15 separate criteria produces a disruption forecast about 180 ms before a standard locked mode detector warning. Single DECAF event analyses have begun on KSTAR, MAST, and NSTX/-U databases with thousands of shot seconds of device operation using from 0.5 to 1 × 106 tested sample times per device. An initial multi-device database comparison illustrates a highly important result that plasma disruptivity does not need to increase as βN increases. Global MHD instabilities, such as resistive wall modes (RWMs), can give the briefest time period of warning before disruption compared to other physics events. In an NSTX database with unstable RWMs, the mode onset, loss of boundary and current control, and disruption event warnings are found in all cases and vertical displacement events are found in 91% of cases. An initial time-dependent reduced physics model of kinetic RWM stabilization created to forecast the disruption chain predicts instability 84% of the time for experimentally unstable cases with a relatively low false positive rate. Instances of the disruption event ... |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| DOI: | 10.1063/5.0133825 |
| DOI: | 10.1063/5.0133825/19824942/032506_1_online.pdf |
| الاتاحة: | http://dx.doi.org/10.1063/5.0133825 https://aip.scitation.org/doi/am-pdf/10.1063/5.0133825 https://pubs.aip.org/aip/pop/article-pdf/doi/10.1063/5.0133825/19824942/032506_1_online.pdf |
| Rights: | https://publishing.aip.org/authors/rights-and-permissions |
| رقم الانضمام: | edsbas.B4487D5E |
| قاعدة البيانات: | BASE |
| DOI: | 10.1063/5.0133825 |
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