LNF: (2021-2025) Fuelling and Impurity Control Studies in the stellarators TJ-II and W7-X using Cryogenic Pellets and Tracer-Encapsulated Solid Pellets (TESPEL): Difference between revisions
m Elena.delaluna moved page LNF: Fuelling and Impurity Control Studies in the stellarators TJ-II and W7-X using Cryogenic Pellets and Tracer-Encapsulated Solid Pellets (TESPEL) (2021-2025) to LNF: (2021-2025) Fuelling and Impurity Control Studies in the stellarators TJ-II and W7-X using Cryogenic Pellets and Tracer-Encapsulated Solid Pellets (TESPEL) |
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6. Experiments in the LHD with continuous lithium power dropping have allowed the creation of a reactor-relevant high-density plasma regime<ref>14</ref>,<ref>15</ref>. This is characterized by increased energy confinement as well as suppressed turbulence and reduced impurity confinement. The transition to this regime is driven by the continuous dropping of Li-powder grains into the plasma. When such plasmas are compared to plasmas without Li-powder the achieved high-performance characteristics include: increased plasma energy & core electron temperature, reduced plasma-wall interaction, and an up to one order of magnitude reduction in plasma turbulence across the whole plasma radius in the frequency range 5 to 500 kHz. In addition, and contrary to expectations for high-density plasmas in stellarators, it is seen, when injecting TESPELs to deposit tracers in the core of this high-performance phase, that impurity confinement is significantly reduced for plasmas with Li powder when compared to confinement in discharges without Li-powder. These new results demonstrate the potential of continuous dropping of Li-powder into stellarator plasmas for simultaneously accessing enhanced confinement regimes while avoiding impurity accumulation. | 6. Experiments in the LHD with continuous lithium power dropping have allowed the creation of a reactor-relevant high-density plasma regime<ref>14</ref>,<ref>15</ref>. This is characterized by increased energy confinement as well as suppressed turbulence and reduced impurity confinement. The transition to this regime is driven by the continuous dropping of Li-powder grains into the plasma. When such plasmas are compared to plasmas without Li-powder the achieved high-performance characteristics include: increased plasma energy & core electron temperature, reduced plasma-wall interaction, and an up to one order of magnitude reduction in plasma turbulence across the whole plasma radius in the frequency range 5 to 500 kHz. In addition, and contrary to expectations for high-density plasmas in stellarators, it is seen, when injecting TESPELs to deposit tracers in the core of this high-performance phase, that impurity confinement is significantly reduced for plasmas with Li powder when compared to confinement in discharges without Li-powder. These new results demonstrate the potential of continuous dropping of Li-powder into stellarator plasmas for simultaneously accessing enhanced confinement regimes while avoiding impurity accumulation. | ||
== | == Dissemination of project results (peer-reviewed publications and conference presentations) == | ||
PEER-REVIEWED ARTICLES ASSOCIATED TO THIS PROJECT (SINCE 2021) | PEER-REVIEWED ARTICLES ASSOCIATED TO THIS PROJECT (SINCE 2021) | ||