Pellet injection as a possible tool for plasma performance improvement

ITER operational scenarios with high field side pellet fuelling are considered. The possibility of reducing the energy losses per edge localized mode (ELM) to an acceptable level is discussed. Requirements of the pellet-fuelling system for desirable ELM energy reduction are obtained. Self-consistent transport simulations of pellet-fuelled scenarios reveal the possibility of operation with moderate ELM losses, plasma density below the Greenwald density, high energy multiplication factor Q ∼ 20 and power across the separatrix above the estimated L–H mode power threshold.