skip to main content

DOE PAGESDOE PAGES

Title: The importance of matched poloidal spectra to error field correction in DIII-D

Optimal error field correction (EFC) is thought to be achieved when coupling to the least-stable "dominant" mode of the plasma is nulled at each toroidal mode number ( n). The limit of this picture is tested in the DIII-D tokamak by applying superpositions of in- and ex-vessel coil set n = 1 fields calculated to be fully orthogonal to the n = 1 dominant mode. In co-rotating H-mode and low-density Ohmic scenarios the plasma is found to be respectively 7x and 20x less sensitive to the orthogonal field as compared to the in-vessel coil set field. For the scenarios investigated, any geometry of EFC coil can thus recover a strong majority of the detrimental effect introduced by the n = 1 error field. Furthermore, despite low sensitivity to the orthogonal field, its optimization in H-mode is shown to be consistent with minimizing the neoclassical toroidal viscosity torque and not the higher-order n = 1 mode coupling.
Authors:
 [1] ;  [1] ;  [2] ;  [3] ;  [1] ;  [3] ;  [1] ;  [2] ;  [2] ;  [1]
  1. General Atomics, San Diego, CA (United States)
  2. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  3. Columbia Univ., New York, NY (United States)
Publication Date:
Grant/Contract Number:
FC02-04ER54698
Type:
Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 21; Journal Issue: 7; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Research Org:
General Atomics, San Diego, CA (United States)
Sponsoring Org:
USDOE Office of Nuclear Energy (NE)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
OSTI Identifier:
1354821

Paz-Soldan, Carlos, Lanctot, Matthew J., Logan, Nikolas C., Shiraki, Daisuke, Buttery, Richard J., Hanson, Jeremy M., La Haye, Robert J., Park, Jong -Kyu, Solomon, Wayne M., and Strait, Edward J.. The importance of matched poloidal spectra to error field correction in DIII-D. United States: N. p., Web. doi:10.1063/1.4886795.
Paz-Soldan, Carlos, Lanctot, Matthew J., Logan, Nikolas C., Shiraki, Daisuke, Buttery, Richard J., Hanson, Jeremy M., La Haye, Robert J., Park, Jong -Kyu, Solomon, Wayne M., & Strait, Edward J.. The importance of matched poloidal spectra to error field correction in DIII-D. United States. doi:10.1063/1.4886795.
Paz-Soldan, Carlos, Lanctot, Matthew J., Logan, Nikolas C., Shiraki, Daisuke, Buttery, Richard J., Hanson, Jeremy M., La Haye, Robert J., Park, Jong -Kyu, Solomon, Wayne M., and Strait, Edward J.. 2014. "The importance of matched poloidal spectra to error field correction in DIII-D". United States. doi:10.1063/1.4886795. https://www.osti.gov/servlets/purl/1354821.
@article{osti_1354821,
title = {The importance of matched poloidal spectra to error field correction in DIII-D},
author = {Paz-Soldan, Carlos and Lanctot, Matthew J. and Logan, Nikolas C. and Shiraki, Daisuke and Buttery, Richard J. and Hanson, Jeremy M. and La Haye, Robert J. and Park, Jong -Kyu and Solomon, Wayne M. and Strait, Edward J.},
abstractNote = {Optimal error field correction (EFC) is thought to be achieved when coupling to the least-stable "dominant" mode of the plasma is nulled at each toroidal mode number (n). The limit of this picture is tested in the DIII-D tokamak by applying superpositions of in- and ex-vessel coil set n = 1 fields calculated to be fully orthogonal to the n = 1 dominant mode. In co-rotating H-mode and low-density Ohmic scenarios the plasma is found to be respectively 7x and 20x less sensitive to the orthogonal field as compared to the in-vessel coil set field. For the scenarios investigated, any geometry of EFC coil can thus recover a strong majority of the detrimental effect introduced by the n = 1 error field. Furthermore, despite low sensitivity to the orthogonal field, its optimization in H-mode is shown to be consistent with minimizing the neoclassical toroidal viscosity torque and not the higher-order n = 1 mode coupling.},
doi = {10.1063/1.4886795},
journal = {Physics of Plasmas},
number = 7,
volume = 21,
place = {United States},
year = {2014},
month = {7}
}