An impurity transport solver has been added to the « CRONOS-ITM » simulator developed inside the European ITM-TF (Integrated Tokamak Modelling Task Force). This new development represents a significant improvement of the CRONOS algorithm which now includes the self-consistent evolution of ion impurities in magnetic fusion plasmas.
The CRONOS-ITM simulator developed inside the European ITM task force was extended with the impurity transport, by integrating a new impurity transport solver. This allows calculating the evolution of multi-charge states ion densities. It uses the Atomic, Molecular, Nuclear and Surface (AMNS) software derived from the atomic database ADAS (Atomic Data and Analysis Structure) in order to get the ionization and recombination coefficients. The radiation losses are also computed owing to AMNS. This new implementation represents a significant improvement of the CRONOS algorithm from which the simulator is derived.
First verification has been carried out on a light impurity test-case: He4, C, and all of their charge states were simulated during several tenth of seconds on a JET-like geometry, during the flat-top phase. The initial state assumes a zero in the impurity ion densities. Analytical sources and transport coefficients are given. Neoclassical terms, temperatures, and current are then computed. One observes, as expected, the accumulation of He4++ as a fusion-like central source and the penetration of C6+ from the edge to the core.
The next verification test will be performed on heavy impurity (tungsten) transport, which is more challenging because of the multiplicity of charge states of such element.
Maj : 11/03/2014 (371)