(IT/P1-9) Simulation of Impurities Behaviour for Basic ITER Scenarios

V.M. Leonov1), V. E. Zhogolev
 
1) RRC ``Kurchatov Institute", Moscow, Russian Federation

Abstract.  Results of simulation of transport and radiation of different impurities for the basic ITER scenarios are presented. Radial profiles of its concentrations and radiation are calculated. Possibility creating of re-radiating layer near plasma periphery without accumulation impurities in the plasma core is considered. Modelling of impurity behaviour was performed by the ZIMPUR code, which has been integrated with the ASTRA transport code for simulation of the bulk plasma parameters. Role of the neoclassical and anomalous impurity transport in different scenarios is considered. It is shown that the neoclassical thermal diffusion assists in screening of the plasma core from impurities in all considered regimes. The most appreciable effect is exhibited for cases where the neoclassical impurity transport is expected in the plasma core: for steady-state reversed shear scenario and for high-Z impurities in ELMy H-mode scenario. Noticeable effect is waiting also for the basic inductive ELMy H-mode scenario for impurities with smaller Z, which more influenced by anomalous transport. Simulations show that impurity radiation increases to the plasma edge as a result of a reduction of the impurity charge state due to charge exchange with hydrogen isotope neutrals. So, possibility of creating a re-radiating layer near the plasma edge without impurity accumulation in the plasma core is demonstrated. Lethal concentrations of different impurities (W, Ar, C, Be, He) are calculated for the basic inductive ITER scenario. At the exceeding of these concentrations, discharge transfers to the L-mode what results of plasma cooling.

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