(IT/P1-20) Beryllium containing plasma interactions with ITER materials

R.P. Doerner1), M. Baldwin1), G. Federici2), J. Hanna1), A. Loarte2), D. Nishijima1), R. Pugno3), K. Schmid3), G. Tynan1), A. Wiltner3), D. Whyte4)
1) University of California at San Diego, La Jolla, CA, USA
2) EFDA-CSU Garching, Germany
3) Max-Plank-Institut fur Plasmaphysik, Garching, Germany
4) MIT Plasma Science & Fusion Center, Cambridge, MA. USA

Abstract.  A beryllium-seeded deuterium plasma is used in PISCES-B to investigate mixed-material erosion and redeposition properties of ITER relevant divertor materials. The beryllium containing plasma simulates the erosion of first wall material into the ITER sol plasma and its subsequent flow toward the carbon divertor plates. The experiments are designed to quantify the behavior of plasma created mixed Be/C and Be/W surfaces. Developing an understanding of the mixed material surface behavior is crucial to accurately predicting the tritium accumulation rate within the ITER vacuum vessel. The temporal evolution of the plasma interactions with the various mixed surfaces are examined to better understand the fundamental mechanisms in play at the surface and to allow scaling of these results to the conditions expected in the ITER divertor. A new periodic heat pulse deposition system is also installed on PISCES-B to simulate the transient temperature excursions of surfaces expected to occur in the ITER divertor during ELMs and other off-normal events. These periodically applied heat pulses allow us to study the effects of transient power loading on the formation, stability and tritium content of mixed-material surfaces that are created during the experiments.

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