Stellarator Theory Activities at Wisconsin - CCH

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Stellarator Theory Activities at Wisconsin - CCH

• 3-D equilibrium/ island physics (M. Schlutt)
• Motivation high-b equilibrium studies a la
  Zarnstorff, Reiman et al--- self-consistent role
  of tranpsort on 3-D MHD equilibrium
• Analytic island estimates - effect of anisotropic
  heat flux on pressure induced islands - resonant
  Pfirsch-Schluter currents
• Numerical modeling tbd - overlap of expertize
  from team NIMROD? (higher order elements -
  Sovinec kinetic modeling ala Held) ---
  collaborate with PPPL/ORNL?
• Neoclassical transport in ECRH heated
  stellarators (J. Seol)
• Motivation High energy electron tails and
  enhanced confinement regimes
• Analytic modeling of 3-D electron distribution
  function with ECRH heating --- symmetry breaking
  B components yield direct losses

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Stellarator Theory Activities at Wisconsin - CCH

• Resistive ballooning modes in stellarators (T.
  Rafiq)
• Motivation Edge fluctuations in HSX, other
  stellarators?
• Conventional treatment in tokamaks relies upon a
  two-scale approach - q p, q (g h)-1/4s1/2
  gtgt 1 (Carreras-Diamond Hastie-Ramos, et al) ---gt
  What happens in the small magnetic shear limit
  (s - gt 0)? 3-D effects are known to affect ideal
  stability ---gt How does this translate to
  resistive ballooning modes in 3-D? Inclusion of
  drift/FLR physics, flow/flow shear- radial
  propagation
• Combo of numerical and analytics
• Kinetic modifications to ideal ballooning
• Motivation non-ideal physics (FLR,
  dissipation)providing quantization of WKB-like
  solutions in ballooning theory
• Prior attempts include a w constribution at the
  ray tracing level - Nevins, et al Wohlbier
• Ballooning/microinstabilities in the presence of
  islands
• Collaboration with Ware, Hudson?