Experimental investigation of neon seeding in the snowflake configuration in TCV

摘要: Recent TCV experiments have examined the effect of poloidal field strength in vicinity x-point diverted configurations on their ability to radiate a large fraction exhaust power. A larger region low is key characteristic “snowflake” configuration, which has been proposed as an alternative divertor solution that decreases power flux targets DEMO-size tokamak. In investigated Ohmic discharges, increasing plasma density and seeding neon both increased radiated up 60–70%. all cases, highest radiation was determined by onset MHD rather than instability. The indicate that, while conventional single-null configuration leads more (+10%) at higher densities, snowflake radiates when impurities (+15%). Extrapolation these modest, but systematic, dependencies geometry reactor-relevant heating device size must be based physics model.