Enhancement of Plasma Burn-through Simulation and Validation in JET
In this paper, a new burn-through model is introduced in detail, and the quantative validation of the simulation results against JET data is presented for the first time. In order to calculate the particle confinement time, a dynamic effective connection length model including an eddy current effect is used assuming ambipolar transonic transport and Bohm diffusion model for parallel and perpendicular particle losses, respectively. Plasma-Surface Interaction (PSI) effect is treated with an impurity sputtering yield and an exponential decay model of the deuterium recycling coefficient. The rate and power coefficients in the Atomic Data and Analysis Structure (ADAS) package are adopted to solve energy and particle balance. The neutral screening effects are taken into account according to particle species, and the sophisticated energy and particle balances are presented. The new burn-through simulation shows good agreement against carbon wall JET data. This indicates that the burn-through simulation can be applied to investigate the key aspect of physics in plasma burn-through and to perform a predictive simulation for ITER start-up.