Selfconsistent perturbed equilibrium with neoclassical toroidal torque in tokamaks
Abstract
Toroidal torque is one of the most important consequences of nonaxisymmetric fields in tokamaks. The wellknown neoclassical toroidal viscosity (NTV) is due to the secondorder toroidal force from anisotropic pressure tensor in the presence of these asymmetries. This work shows that the firstorder toroidal force originating from the same anisotropic pressure tensor, despite having no flux surface average, can significantly modify the local perturbed force balance and thus must be included in perturbed equilibrium selfconsistent with NTV. The force operator with an anisotropic pressure tensor is not selfadjoint when the NTV torque is finite and thus is solved directly for each component. This approach yields a modified, nonselfadjoint EulerLagrange equation that can be solved using a variety of common driftkinetic models in generalized tokamak geometry. The resulting energy and torque integral provides a unique way to construct a torque response matrix, which contains all the information of selfconsistent NTV torque profiles obtainable by applying nonaxisymmetric fields to the plasma. This torque response matrix can then be used to systematically optimize nonaxisymmetric field distributions for desired NTV profiles. Published by AIP Publishing.
 Authors:
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 Publication Date:
 Research Org.:
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC24)
 OSTI Identifier:
 1377823
 Alternate Identifier(s):
 OSTI ID: 1348951
 Grant/Contract Number:
 AC0276CH03073
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Physics of Plasmas
 Additional Journal Information:
 Journal Volume: 24; Journal Issue: 3; Journal ID: ISSN 1070664X
 Publisher:
 American Institute of Physics (AIP)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; bananadrift transport; momentum dissipation; plasmas; stability
Citation Formats
Park, JongKyu, and Logan, Nikolas C. Selfconsistent perturbed equilibrium with neoclassical toroidal torque in tokamaks. United States: N. p., 2017.
Web. doi:10.1063/1.4977898.
Park, JongKyu, & Logan, Nikolas C. Selfconsistent perturbed equilibrium with neoclassical toroidal torque in tokamaks. United States. doi:10.1063/1.4977898.
Park, JongKyu, and Logan, Nikolas C. Wed .
"Selfconsistent perturbed equilibrium with neoclassical toroidal torque in tokamaks". United States.
doi:10.1063/1.4977898. https://www.osti.gov/servlets/purl/1377823.
@article{osti_1377823,
title = {Selfconsistent perturbed equilibrium with neoclassical toroidal torque in tokamaks},
author = {Park, JongKyu and Logan, Nikolas C.},
abstractNote = {Toroidal torque is one of the most important consequences of nonaxisymmetric fields in tokamaks. The wellknown neoclassical toroidal viscosity (NTV) is due to the secondorder toroidal force from anisotropic pressure tensor in the presence of these asymmetries. This work shows that the firstorder toroidal force originating from the same anisotropic pressure tensor, despite having no flux surface average, can significantly modify the local perturbed force balance and thus must be included in perturbed equilibrium selfconsistent with NTV. The force operator with an anisotropic pressure tensor is not selfadjoint when the NTV torque is finite and thus is solved directly for each component. This approach yields a modified, nonselfadjoint EulerLagrange equation that can be solved using a variety of common driftkinetic models in generalized tokamak geometry. The resulting energy and torque integral provides a unique way to construct a torque response matrix, which contains all the information of selfconsistent NTV torque profiles obtainable by applying nonaxisymmetric fields to the plasma. This torque response matrix can then be used to systematically optimize nonaxisymmetric field distributions for desired NTV profiles. Published by AIP Publishing.},
doi = {10.1063/1.4977898},
journal = {Physics of Plasmas},
number = 3,
volume = 24,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2017},
month = {Wed Mar 01 00:00:00 EST 2017}
}

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