Elements of H-mode pedestal structure
نویسندگان
چکیده
Abstract This paper reviews current understanding of key physics elements that control the H-mode pedestal structure, which exists at boundary magnetically confined plasmas. The structure interest is width, height and gradient temperature, density pressure profiles in pedestal. Emphasis placed on obtained from combined experimental, theoretical simulation work results observed multiple machines. Pedestal are determined by self-consistent interaction sources, transport magnetohydrodynamic limits. heat source primarily deposited core flowing to computed modeling experimental data generally well understood. Neutrals periphery plasma provide dominant particle has a complex spatial very difficult measure poorly For typical operation, achievable limited repetitive, transient instabilities. First principles models peeling–ballooning modes able explain In some regimes, instability occurs below predicted limits these remain unexplained. Several mechanisms have been identified as plausible sources transport. These include neoclassical processes for ion several turbulent processes, driven steep gradients, electron Reduced successfully or top. Firming up remains primary challenge developing more complete predictive models.
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ژورنال
عنوان ژورنال: Plasma Physics and Controlled Fusion
سال: 2023
ISSN: ['1361-6587', '0741-3335']
DOI: https://doi.org/10.1088/1361-6587/acd478