Experimental Study and Numerical Simulation of Material Migration in the VISIONI Plasma Simulator

The impending energy crisis is one of the toughest problems mankind will have to face in the near future. Thermonuclear fusion is a promising alternative sustainable energy source. However, there are still several obstacles on the road towards the first power plant. One of the issues is material migration caused by impact of plasma particles on the inner reactor materials. It is of primordial importance to get a better understanding of erosion and deposition to make reliable predictions for future devices. During the first part material migration experiments in the TEXTOR tokamak at Forschungszentrum Jülich were simulated with the ERO impurity transport code. This study demonstrated the importance of enhanced re-erosion of deposited species for future thermonuclear fusion reactors. This enhanced re-erosion was studied further in the second part by similar studies in the VISIONI plasma simulator at the Belgian Nuclear Research Centre. The magnetic field and the plasma in VISIONI were first characterized by combining analytical calculations, measurements and computer simulations. This allowed the development of a new version of ERO for VISIONI. Eventually material migration experiments were performed in VISIONI and simulated with the new version of ERO, contributing to a better understanding of the enhanced re-erosion.