Modelling the erosion/deposition pattern of the Tore Supra Toroidal Pumped Limiter

Abstract

This paper aims at understanding the main processes responsible for the erosion/deposition pattern observed on the surface of the Toroidal Pumped Limiter of Tore Supra, using the 3D local impurity transport code ERO. The influence of the plasma impurity content, CX-flux and surface temperature on the global carbon balance and erosion/deposition pattern is discussed. Main results are (1) that considering medium-range transport of C ions is mandatory for reproducing the main characteristics of the global C balance and erosion/deposition pattern, (2) that impurities and CX-atoms increase the erosion by a factor⩽2 (without changing the net/gross erosion ratio), and (3) that chemical erosion is governed by the re-erosion of deposits, which depends strongly on the surface temperature.