TY - JOUR
T1 - Influence of MHD effects and edge conditions on ITER helium ash accumulation and sustained ignition
AU - Redi, M. H.
AU - Cohen, S. A.
N1 - Funding Information:
We are glad to acknowledge discussions with J. Manickam, D. Monticello, DR. Mikkelsen, W.Park and D. Stotler. This work was supported by US Department of Energy Contract No. DE-AC02-76CHO-3073.
PY - 1990/12/3
Y1 - 1990/12/3
N2 - Dilution of reacting species by build-up of helium ash and its effect on ignition in the ITER tokamak have been studied in a series of simulations with the one-dimensional BALDUR transport code. Thermal diffusivities, obtained from ITER scaling laws and with radial variations observed in JET, gave τe ≈ 2-4 s. Refuelling of deuterium and tritium maintained constant electron density, while carbon recycling was 100% and the helium ash recycling was varied from 1.0 to 0.5. Including MHD effects, specifically sawteeth and beta limits, we find that ignition can be sustained for 200 s with Rhelium = 0.95. These simulations, the only non-zero-dimensional, time-dependent simulations thus far made for ITER plasmas, emphasize that edge plasma conditions, MHD behavior, and helium particle transport are critical synergistic issues for sustained ignition.
AB - Dilution of reacting species by build-up of helium ash and its effect on ignition in the ITER tokamak have been studied in a series of simulations with the one-dimensional BALDUR transport code. Thermal diffusivities, obtained from ITER scaling laws and with radial variations observed in JET, gave τe ≈ 2-4 s. Refuelling of deuterium and tritium maintained constant electron density, while carbon recycling was 100% and the helium ash recycling was varied from 1.0 to 0.5. Including MHD effects, specifically sawteeth and beta limits, we find that ignition can be sustained for 200 s with Rhelium = 0.95. These simulations, the only non-zero-dimensional, time-dependent simulations thus far made for ITER plasmas, emphasize that edge plasma conditions, MHD behavior, and helium particle transport are critical synergistic issues for sustained ignition.
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U2 - 10.1016/0022-3115(90)90057-T
DO - 10.1016/0022-3115(90)90057-T
M3 - Article
AN - SCOPUS:0025546914
SN - 0022-3115
VL - 176-177
SP - 262
EP - 267
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
IS - C
ER -