Modelling the energy deposits in a tokamak - Application to limiter and ergodic divertor configurations in Tore Supra
The layer of plasma beyond the last closed flux surface, the SOL, is characterised by its radial thickness, lambda. The dependence of this characteristic length on different plasma parameters, such as density, current and magnetic field, has been established on Tore Supra. The main conclusion is that lambda is almost independent of plasma conditions in Tore Supra. The code THOR takes the real geometry of all the limiters and of the magnetic equilibrium into account. It gives the image of the plasma on the walls. It combines parallel motion with perpendicular diffusion, whose random character is obtained by a Monte Carlo algorithm. The code permits disturbance of the initial magnetic equilibrium, so its capacities have been improved by adding perturbations induced by an ergodic divertor. Numerical results agree with experimental observations. In some cases they raise doubts about the physical models. An analytical model is developed which explains the features of real energy deposits on the first wall, which do not match predictions of the classical model.
Bibliographic Reference: Report: EUR-CEA-FC-1488 FR (1993) 199 pp.
Availability: Available from CEA, Département de Recherches sur la Fusion Contrôlée, Saint-Paul-lez-Durance (FR)
Record Number: 199311098 / Last updated on: 1994-11-29
Original language: fr
Available languages: fr