Plasma Heat-Flux Dispersal for ACT1 Divertor Configurations

Simulations of the heat flux on plasma-facing components from core exhaust plasma are reported for two possible ACT1 divertor configurations. One configuration uses divertor plates strongly inclined with respect to the poloidal magnetic flux surfaces similar to that planned for ITER and results in a partially detached divertor plasma. The second configuration has divertor plates orthogonal to the flux surfaces, which leads to a fully detached divertor plasma if the width of the divertor region is sufficient. Both configurations use scrape-off layer radiation from seeded impurities to yield an acceptable peak heat flux of ∼10 MW/m² or smaller on the divertor plates and chamber walls. The simulations are performed with the UEDGE two-dimensional transport code to model both plasma and neutral components with some supplementary neutral modeling performed with the DEGAS 2 Monte Carlo code.