Speaker
Description
See the full abstract here:
http://ocs.ciemat.es/EPS2019ABS/pdf/P4.1086.pdf
The development of non-inductive current drive methods is a central problem on the way of a fusion reactor development within the tokamak concept. The low-hybrid (LH) method of current maintenance can potentially be used in solving this problem, since it has one of the highest efficiencies of current drive [1]. This method is proposed as a possible technique for current generation at the middle and periphery radii of plasma core for the current profile broadening in ITER, which will operate with a mixture of heavy hydrogen isotopes [2]. Recently the isotope effect on the LHCD efficiency dependence on main parameters of hydrogen and deuterium plasmas have been studied at the FT-2 tokamak [3]. To interpret the experimental results indicating the high LHCD efficiency complex simulations of the propagation and absorption of LH waves in the FT-2 plasma were performed. The Grill3D code [4] was used to calculate the parallel refractive index spectrum of the lower hybrid wave launched into the plasma by two-waveguide antennae. The magnitude and direction of the current generated by the lower hybrid wave were computed using the Fast Ray Tracing Code (FRTC) [5], the calculated LH wave spectrum, and the measured profiles of the plasma parameters. The magnetic equilibrium of the plasma column was provided by the ASTRA code [6] with using of the measured radial profiles of the plasma parameters. However simulations performed in [3] did not take into account the effect of the residual inductive electric field on the electron distribution function, generation of super-thermal electrons and hence on the LHCD efficiency. In the present work a new one-dimensional approach to the lower hybrid current drive modelling in the presence of the inductive electric field suggested recently in [8] is applied to calculate LHCD for hydrogen and deuterium plasmas at FT-2 experiments. The simulation results are compared to the experimental data.
[1] N.J. Fisch, Mod. Phys. Rew. 59 1987 [2] P. Bonoli, Phys. Plasmas 21, 2014 [3] S.I. Lashkul et al Nucl. Fusion 55 (2015) 073019 [4] M. A. Irzak and O. N. Shcherbinin, Nucl. Fusion 35, 1341 (1995) [5] A.D. Piliya, A.N. Saveliev, JET Joint Undertaking, Abingdon, Oxfordshire, OX14 3EA, 1998 [6] G.V.Pereverzev and P.N. Yushmanov, Automated System for TRansport Analysis IPP-Report IPP 5/98, (2002) [7] A.N. Saveliev, EPJ Web of Conferences 157, 03045 (2017)
