Scenario Development for FAST in the View of ITER and DEMO

The Fusion Advanced Studies Torus (FAST) aims at contributing to the exploitation of ITER and to tackle innovative DEMO technology. FAST has been designed to explore integrated scenarios studying: a) relevant plasma-wall interaction problems, with a large power load (P/R ~ 22) and full metallic wall; b) operational problems in regimes with relevant fusion parameters; c) non-linear dynamics of alpha particle in burning plasmas. Recently three new FAST scenarios have been developed. 1) FAST load assembly has been conceived to accommodate 10MW of NNBI plus 30MW of ICRH; this allows producing fast particle populations with different anisotropy and profile localization. 2) One of the FAST proposal critical points is the extensive use of ICRH power with first wall and divertor in full tungsten; a variant of the reference scenario has been studied, where 15 MW of ICRH have been replaced with 15MW of ECRH at 170 GHz. 3) Recent experimental results show the necessity of suitable magnetic shear and robust plasma rotation to operate with a reliable ITB. C-MOD experience shows the possibility of achieving ITB operations at high plasma density even without external momentum injection, due to intrinsic rotation. Based on such experimental results and recent developments in the theory of momentum transport, a significant and peaked rotation profile can be envisaged in FAST. In order to study the plasma wall interactions in conditions approaching those of ITER and DEMO, the edge behavior has been analyzed in great detail by means of the EDGE2D/ EIRENE codes. These investigations show the capability of FAST of operating with a large wall load (up to 18MWm-2), while maintaining it within tolerable limits by working at very high density, with a radiative edge.