ERO2.0 Benchmarking of Material Mixing for Local and Global Beryllium Transport in JET *

Plasma-material interactions (PMI) is a challenging topic because it affects the lifetime of wall components and plasma performance. The fully 3D ERO 2.0 Monte Carlo code is capable of modeling global impurity transport, which defines the erosion/deposition patterns in a reactor. A material mixing model was implemented in the ERO2.0 code and successfully benchmarked against its predecessor, ERO, for local impurity transport along the JET tungsten divertor tile 5. The case for benchmark corresponds to inter-ELM plasma conditions, with experimentally fitted exponentially decaying plasma profiles along the private flux region (PFR) and the scrape off layer. Because ERO was restricted to local studies, certain assumptions like the constant level of background Be was assumed. With the ERO2.0 improvements, it is possible to see how a Be source in the main chamber affects the Be deposition in the W divertor and the Be/W mixed layer formation. Two cases are considered: (1) a fixed beryllium background concentration and (2) beryllium sources injected at the outer mid-plane limiters to mimic the main wall beryllium source and providing the beryllium flux to the divertor. Global modeling successfully recreates beryllium buildup in the PFR along tile 5 as expected from the local benchmark.