Burn Control Study Using Burning Plasma Simulation Experiments in JT-60U

Burn control simulation experiments in JT-60U

“…By applying only group A (NB), we could make a simulated thermal excursion [3]. The zero-dimensional calculation for particle and power balance showed that the runaway increase of the NB power for the ␣-particle heating simulation triggered by rising G well reproduces a thermal excursion triggered by improved confinement [4].…”

“…In order to study the coupling in non-burning plasmas, a burning plasma simulation scheme has been developed [3,4]. In this scheme, the NB heating power proportional to the DD neutron yield rate was applied using a real-time control system for the simulation of ␣-particle heating.…”

Extended hybrid kinetic-magnetohydrodynamic model for ignited burning plasmas

“…Ignition in burning plasma is an important stage of thermonuclear fusion reaction in which the electrically charged α particles resulting from the fusion reaction can heat up the plasma and enable the reaction to achieve a self-sustained condition [1][2][3][4]. Thus, the fusion reaction passes a balance condition of output alpha power P α to the external input power P in (from neutral beam injection (NBI), resonance frequency (RF), and Ohmic heating), beyond which external heating is no more necessary [3,5,6]. This balance condition corresponds to P α /(P α + P in ) ≥ 1/2 or Q ≥ 5 in term of the power gain Q = P out /P in , where, P out = P α +P n ≈ 5P α [1,4,6].…”

“…Thus, the fusion reaction passes a balance condition of output alpha power P α to the external input power P in (from neutral beam injection (NBI), resonance frequency (RF), and Ohmic heating), beyond which external heating is no more necessary [3,5,6]. This balance condition corresponds to P α /(P α + P in ) ≥ 1/2 or Q ≥ 5 in term of the power gain Q = P out /P in , where, P out = P α +P n ≈ 5P α [1,4,6]. It means, at the higher value of the power gain (Q > 5), there would be a substantial amount of alpha particles (both energetic and thermalized) in addition to the thermalized electrons and ions in the core of fusion plasma.…”

“…Experiments in Tokamak Fusion Test Reactor (TFTR), Joint European Torus (JET), and JT-60U have confirmed the alpha particle generation even though it could not reach the state of self-sustained nuclear reactions [1,2,4,6]. Due to the lack of adequate datas, there has been very less discussion on the effects of the alpha particles and alpha-particle physics remain one of the active research area for fusion plasma [10].…”