Helium transport in advanced tokamak scenarios with internal transport barrier
The results are presented of investigations on advanced scenarios for plasmas of next-generation tokamaks by means of a 1.5-dimensional transport code. The role of thermonuclear alpha particles and helium ash is analysed by a two-group model and by introducing experimentally validated mixed Bohm/gyroBohm models on the assumption that the diffusion of helium ash can be treated like the diffusion of bulk plasma ions. Recycling of helium ash is modelled by introducing a wall source. Results are presented of parameter studies presenting the equilibrium helium fraction as a function of the recycling factor. It is shown that for a given scenario, the fraction of effective helium confinement time and energy confinement time is a time-dependent quantity and not a constant, as was assumed in earlier research.
Bibliographic Reference: An article published in: Fusion Technology, Vol.39 (2001), pp.119-126
Record Number: 200113835 / Last updated on: 2001-10-04
Original language: en
Available languages: en