Plasma–surface interactions during tokamak disruptions and rapid shutdowns

• Published in: Journal of nuclear materials Vol. 415; no. 1; pp. S27 - S34
• Main Authors: Hollmann, E.M., Arnoux, G., Commaux, N., Eidietis, N.W., Evans, T.E., Granetz, R.S., Huber, A., Humphreys, D.A., Izzo, V.A., James, A.N., Jernigan, T.C., Lehnen, M., Maddaluno, G., Paccagnella, R., Parks, P.B., Philipps, V., Reinke, M.L., Rudakov, D.L., Saint-Laurent, F., Sizyuk, V., Strait, E.J., Wesley, J.C., Wong, C.P.C., Yu, J.H.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01-08-2011; Elsevier
• Subjects: Applied sciences; Controled nuclear fusion plants; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fission nuclear power plants; Fuels; Installations for energy generation and conversion: thermal and electrical energy; Nuclear fuels; Tokamak; Nuclear fusion reactor; Beryllium; Numerical simulation; Disruption; Gas injection; Surface plasma interaction; Damaging; Nuclear reactor
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2010.10.009

Recent progress in understanding of disruptions and in developing methods to avoid disruption damage is presented. Nearly complete mitigation of conducted heat loads has been achieved with high-Z gas jet shutdown. The resulting local radiation heat flash melting in the main chamber might be a concern in ITER, especially with beryllium walls. During the current quench, significant vessel forces can occur due to halo currents Ihalo; however, these are found to fall reliably below a boundary of (halo current fraction times halo current peaking factor) <0.7 both experimentally and numerically. Numerical simulations indicate that runaway electrons (REs) could cause serious damage to hard-to reach components in ITER, making their suppression a high priority. During the current quench, less than 20% of the density required for collisional suppression of REs appears to have been achieved. Collisional suppression of REs may have been achieved, however, in full-current RE beams with gas injection.