Integrated power exhaust modelling for DEMO with lithium divertor

Influence of Krypton Seeding on EU DEMO Operation with Lithium Divertor

“…Level of the Li influx rate (C Li ' 2 Â 10 24 s À1 ) and the maximum surface temperature (T max surf [ 750 C) found in the simulations (at low Kr seeding values) are comparable to those where thermal Journal of Fusion Energy sputtering was neglected (see Ref. [1]). The noticable difference is that the plasma conditions in the divertor region at low Kr seeding found in the simulations when thermal sputtering is included correspond to the conditions found in Ref.…”

“…As was observed in [1] evaporation was the dominant source of lithium in the plasma. However, when thermal sputtering is included, self-sputtering and evaporation contribute equally at low level of Kr concentration (see Fig.…”

“…The noticable difference is that the plasma conditions in the divertor region at low Kr seeding found in the simulations when thermal sputtering is included correspond to the conditions found in Ref. [1] for higher values of tungsten substrate depth (d W ' 15 À 20 mm) rather than d W ¼ 10 mm used in this paper. One may conclude that including thermal sputtering results in high evaporation regime taking place for lower values of the LMD tungsten substrate depth.…”

“…[1] we restrict here to listing the parameters used in the simulation and to the description of the sputtering model updated for the purpose of this study and refer the reader to Ref. [1] and references therein for more detailed description of the code. The value of radial anomalous transport in the SOL D SOL rad ¼ 0:42 m 2 =s.…”

“…Modelling of DEMO reactor with liquid lithium divertor indicates [1] that the goal of a divertor power load reduction may be achieved by the fuel ions dilution in the core and consequently the reduction of the fusion power. Effectively, DEMO operation with liquid lithium divertor is not excluded but results in lower fusion gain factor, Q.20 compared to Q ' 35 in the case of tungsten divertor with additional neon or argon seeding [2].…”