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Title: Experimental and modeling uncertainties in the validation of lower hybrid current drive

Journal Article · · Plasma Physics and Controlled Fusion
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  1. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  2. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center
  3. CompX, Del Mar, CA (United States)
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Our work discusses sources of uncertainty in the validation of lower hybrid wave current drive simulations against experiments, by evolving self-consistently the magnetic equilibrium and the heating and current drive profiles, calculated with a combined toroidal ray tracing code and 3D Fokker–Planck solver. The simulations indicate a complex interplay of elements, where uncertainties in the input plasma parameters, in the models and in the transport solver combine and compensate each other, at times. It is concluded that ray-tracing calculations should include a realistic representation of the density and temperature in the region between the confined plasma and the wall, which is especially important in regimes where the LH waves are weakly damped and undergo multiple reflections from the plasma boundary. Uncertainties introduced in the processing of diagnostic data as well as uncertainties introduced by model approximations are assessed. We show that, by comparing the evolution of the plasma parameters in self-consistent simulations with available data, inconsistencies can be identified and limitations in the models or in the experimental data assessed.

Research Organization:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Organization:
USDOE Office of Science (SC)
Grant/Contract Number:
AC02-CH0911466; FC02-99ER54512
OSTI ID:
1338617
Alternate ID(s):
OSTI ID: 1275970
Journal Information:
Plasma Physics and Controlled Fusion, Vol. 58, Issue 9; ISSN 0741-3335
Publisher:
IOP ScienceCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 12 works
Citation information provided by
Web of Science

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Cited By (2)

Integrated Tokamak modeling: When physics informs engineering and research planning journal May 2018
Orchestrating TRANSP Simulations for Interpretative and Predictive Tokamak Modeling with OMFIT journal February 2018

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