Stage 2018 - PT/GDIPP
Transport in the edge plasma of tokamaks remains one of the main unknows for future magnetic fusion devices such as ITER. The understanding of the physical mechanims explaining particle and energy fluxes in the boundary of the plasma is fundamental to determine and optimize the performances as well as the life expectancy of plasma facing components. It is now acknowledged that turbulence plays a key role in transport perpendicular to the magnetic field. Adressing this non linear problem requires the usage of complex numerical tools. The recent exploitation of 3D global, so-called "first-principle", codes, which do not make use of ad-hoc assumptions to simplifiy the description of perpendicular transport, demonstrated the importance of multi-scale interactions in the dynamics of transport in the edge plasma. This also implies that the geometry of the confining magnetic field and of the reactor's wall are key factors in the physics at play. Recent simulations performed with the TOKAM3X code, developped jointly between IRFM and Aix-Marseille Université, confirm this impact of the geometry on turbulent transport but the detailed physical understanding is not complete.
During this intership, we propose to analyse further the impact of the magnetic geometry on turbulent transport in the edge plasma. The TOKAM3X code will be used to perform simulations in carefully chosen geometries in order to analyse the impact of specific geometrical aspects, such as elongation or triangularity. The output of simulations will then be analysed with existing or to-be-developped post-treatment tools.