Energy and particle transport modelling with a time dependent combined core and edge transport code

A new time dependent code has been developed by linking the 1 1/2 D core plasma transport code JETTO to the 2D edge plasma transport code EDGE2D/NIMBUS. The code includes a combined Bohm-gyro-Bohm type transport model for energy transport in the plasma core, and this has been extended to include particle transport and a neoclassical transport barrier at the plasma edge for the simulation of JET hot ion H modes. Outside the separatrix the transport coefficients extrapolated from the model are assumed to be constant. It is shown that the code gives a completely consistent time dependent simulation of the measured plasma profiles across the entire cross section of hot-ion ELM free discharges, including the scrape-off layer and divertor regions. The code also predicts that the ballooning stability limit is reached when a giant type 1 ELM appears in experiments. (author). 9 refs, 5 figs, 1 tab