A novel feedback algorithm for simulating controlled dynamics and confinement in the advanced reversed-field pinch
2005 (English)In: Physics of Plasmas, ISSN 1070-664X, Vol. 12, no 6, 062502- p.Article in journal (Refereed) Published
In the advanced reversed-field pinch (RFP), the current density profile is externally controlled to diminish tearing instabilities. Thus the scaling of energy confinement time with plasma current and density is improved substantially as compared to the conventional RFP. This may be numerically simulated by introducing an ad hoc electric field, adjusted to generate a tearing mode stable parallel current density profile. In the present work a current profile control algorithm, based on feedback of the fluctuating electric field in Ohm's law, is introduced into the resistive magnetohydrodynamic code DEBSP [D. D. Schnack and D. C. Baxter, J. Comput. Phys. 55, 485 (1984); D. D. Schnack, D. C. Barnes, Z. Mikic, D. S. Marneal, E. J. Caramana, and R. A. Nebel, Comput. Phys. Commun. 43, 17 (1986)]. The resulting radial magnetic field is decreased considerably, causing an increase in energy confinement time and poloidal beta. It is found that the parallel current density profile spontaneously becomes hollow, and that a formation, being related to persisting resistive g modes, appears close to the reversal surface.
Place, publisher, year, edition, pages
2005. Vol. 12, no 6, 062502- p.
POLOIDAL CURRENT DRIVE; FLUCTUATION; TRANSPORT; BETA
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-6332DOI: 10.1063/1.1924556ISI: 000229700400034ScopusID: 2-s2.0-24144484884OAI: oai:DiVA.org:kth-6332DiVA: diva2:11017
QC 201008242006-11-132006-11-132010-11-01Bibliographically approved