Dynamic analysis of mixed ion beams/materials effects on the performance of ITER-like devices

Future reactors, e.g., ITER can require multiple plasma facing components (PFC) surfaces such as Be, C and W. Soon after the start of normal operation as well as after plasma transient events the surfaces can behave much differently than the original surfaces, and transport of eroded particles can influence plasma performance and component lifetime. A new dynamic version of ITMC-DYN, part of the HEIGHTS package, is therefore developed for detailed investigation of plasma material interaction in multiple/mixed materials environment. Models consider simultaneous ion penetration and mixing, scattering, reflection, physical and chemical sputtering, dynamic surface evolution/modification, thermal diffusion, hydrogen molecular recombination, and surface segregation. The package tracks time and temperature-dependent dynamic changes in surface erosion/growth rate, and material composition and structure. Initial results show significant influence of mixed beams/materials on PFC erosion, material evolution, hydrogen isotope behavior, and potential plasma performance. We analyzed recent experiments on hydrogen isotope retention in ITER relevant mixed materials, and predict the behavior of hydrogen (retention, diffusion, molecular recombination, and blisters formation). Excellent code/data agreement is obtained and conditions of blister formation are identified and explained. (C) 2010 Elsevier B.V. All rights reserved.