RF Modeling Capabilities for NSTX: Edge Plasma and Non thermal Ion effects

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RF Modeling Capabilities for NSTX Edge Plasma
and Non thermal Ion effects

• P.T. Bonoli and J.C. Wright, PSFC, MIT
• C.K. Phillips and D. McCune, PPPL
• M. Brambilla, IPP, Garching
• NSTX Research Forum
• September 22-24, 2004
• PPPL, Princeton, NJ

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Important RF Physics Issues for NSTX

• Understanding the interaction of HHFW and fast NB
  ions
• Requires an accurate closed loop computation
  between full-wave (or ray tracing) module and
  Fokker Planck code.
• Understanding coupling physics of HHFW with low
  density plasma in close proximity to antenna
  current strap
• Usual treatment assumes current strap is in
  vacuum.
• We are hoping to provide a useful tool to address
  these issues.

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Significant Enhancements have been Completed on
the ICRF Full-wave Solver TORIC

• Work funded through many sources RF SciDAC
  Initiative, NSTX Collaborative Grant, PPPL, MIT,
  IPP.
• Major rewrite of code to be valid in the HHFW
  regime (IPP and MIT) TORIC4
• Code now reads and uses EFIT equilibria and
  experimental profiles of density and temperature
  (IPP and PPPL).
• Code implemented on both serial and parallel
  computing architectures (MIT Beowulf cluster).

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Currently Three Major Physics Upgrades to TORIC
are Underway

• Rewrite conductivity operator to be valid for
  arbitrary particle distributions (PPPL, MIT)
• Study HHFW NBI interaction in NSTX
• Extend plasma to conducting wall with electric
  field boundary condition at wall
• Study ICRF antenna coupling in NSTX under more
  realistic edge plasma conditions
• Implementation of TORIC4 in TRANSP (PPPL, IPP,
  MIT)

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NSTX Profiles - 112705
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HHFW Simulation for NSTX (112705) Using
TORIC4B00.42T, Ip0.92 MA, k//ANT7.7 m-1,
f030 MHzTORIC4 - 240 Radial elements and 255
Poloidal Modes)