High–confinement radiative L–modes in ASDEX Upgrade

Experiments have been performed in the ASDEX Upgrade tokamak where plasmas are kept just below the H--mode threshold using feedback on the radiated power via seeded impurity. The resulting high--power L--modes show high confinement properties and no ELM activity due to the reduced pedestal height. The physics of these high--confinement L--modes is explored by means of integrated modeling to clarify the origin of the improved confinement.

Recent progress in modeling ICRF-edge plasma interactions with application to ASDEX Upgrade

This paper summarizes recent progress in modeling the interaction between Ion Cyclotron Range of Frequency (ICRF) waves and edge plasma with application to ASDEX Upgrade. The basic theories, the development of ICRF and edge plasma codes, the integrated modeling methods and some key results are reviewed. In particular, the following physical aspects are discussed: 1. ICRF power coupling; 2. Slow wave propagation; 3. ICRF-rectified sheath; 4. ICRF-induced convection; 5. ICRF-edge turbulence interaction. Moreover, comprehensive integrated modeling strategies by including all necessary codes in one package and solving multiple physical issues self-consistently are discussed.

Development of a system SIEMNED for integrated modeling of processes in tokamak installations

The paper describes a new system of integrated modelling SIEMNED (Software and Information Environment for Modelling and Numerical support of Experiments on complex Devices) designed for numerical support of experiments on tokamak installations. Also discussed are the results of its application to the modelling of discharge scenarios at the T-15 MD installation, which is currently being prepared for the physical launch.