Helium Accumulation: A 1½-Dimensional Sensitivity Study

A 1½-dimensional transport code for an ARIES-I-type plasma is used to explore the sensitivity of ash buildup to changes in transport coefficients. The code is also used to examine the effect of helium edge recycling. Ash buildup is shown to be sensitive to the ratio of the helium to the fuel ion transport coefficient and to the magnitude of the helium inward pinch velocity.