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Title: Predict-first experimental analysis using automated and integrated magnetohydrodynamic modeling

Abstract

An integrated-modeling workflow has been developed in this paper for the purpose of performing predict-first analysis of transient-stability experiments. Starting from an existing equilibrium reconstruction from a past experiment, the workflow couples together the EFIT Grad-Shafranov solver [L. Lao et al., Fusion Sci. Technol. 48, 968 (2005)], the EPED model for the pedestal structure [P. B. Snyder et al., Phys. Plasmas 16, 056118 (2009)], and the NEO drift-kinetic-equation solver [E. A. Belli and J. Candy, Plasma Phys. Controlled Fusion 54, 015015 (2012)] (for bootstrap current calculations) in order to generate equilibria with self-consistent pedestal structures as the plasma shape and various scalar parameters (e.g., normalized β, pedestal density, and edge safety factor [q 95]) are changed. These equilibria are then analyzed using automated M3D-C1 extended-magnetohydrodynamic modeling [S. C. Jardin et al., Comput. Sci. Discovery 5, 014002 (2012)] to compute the plasma response to three-dimensional magnetic perturbations. This workflow was created in conjunction with a DIII-D experiment examining the effect of triangularity on the 3D plasma response. Several versions of the workflow were developed, and the initial ones were used to help guide experimental planning (e.g., determining the plasma current necessary to maintain the constant edge safety factor in various shapes).more » Subsequent validation with the experimental results was then used to revise the workflow, ultimately resulting in the complete model presented here. We show that quantitative agreement was achieved between the M3D-C1 plasma response calculated for equilibria generated by the final workflow and equilibria reconstructed from experimental data. A comparison of results from earlier workflows is used to show the importance of properly matching certain experimental parameters in the generated equilibria, including the normalized β, pedestal density, and q 95. On the other hand, the details of the pedestal current did not significantly impact the plasma response in these equilibria. A comparison to the experimentally measured plasma response shows mixed agreement, indicating that while the equilibria are predicted well, additional analysis tools may be needed. In conclusion, we note the implications that these results have for the success of future predict-first studies, particularly the need for scans of uncertain parameters and for close collaboration between experimentalists and theorists.« less

Authors:
ORCiD logo [1]; ORCiD logo [1];  [1]; ORCiD logo [1];  [1]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [2];  [1]
  1. General Atomics, San Diego, CA (United States)
  2. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Publication Date:
Research Org.:
General Atomics, San Diego, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
OSTI Identifier:
1436754
Alternate Identifier(s):
OSTI ID: 1436208
Grant/Contract Number:  
FG02-95ER54309; FC02-06ER54873; FC02-04ER54698; SC0015499
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 25; Journal Issue: 5; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; plasma confinement; numerical modeling; tokamaks; magnetohydrodynamics; plasma instabilities

Citation Formats

Lyons, B. C., Paz-Soldan, C., Meneghini, O., Lao, L. L., Weisberg, D. B., Belli, E. A., Evans, T. E., Ferraro, N. M., and Snyder, P. B. Predict-first experimental analysis using automated and integrated magnetohydrodynamic modeling. United States: N. p., 2018. Web. doi:10.1063/1.5025838.
Lyons, B. C., Paz-Soldan, C., Meneghini, O., Lao, L. L., Weisberg, D. B., Belli, E. A., Evans, T. E., Ferraro, N. M., & Snyder, P. B. Predict-first experimental analysis using automated and integrated magnetohydrodynamic modeling. United States. doi:10.1063/1.5025838.
Lyons, B. C., Paz-Soldan, C., Meneghini, O., Lao, L. L., Weisberg, D. B., Belli, E. A., Evans, T. E., Ferraro, N. M., and Snyder, P. B. Mon . "Predict-first experimental analysis using automated and integrated magnetohydrodynamic modeling". United States. doi:10.1063/1.5025838. https://www.osti.gov/servlets/purl/1436754.
@article{osti_1436754,
title = {Predict-first experimental analysis using automated and integrated magnetohydrodynamic modeling},
author = {Lyons, B. C. and Paz-Soldan, C. and Meneghini, O. and Lao, L. L. and Weisberg, D. B. and Belli, E. A. and Evans, T. E. and Ferraro, N. M. and Snyder, P. B.},
abstractNote = {An integrated-modeling workflow has been developed in this paper for the purpose of performing predict-first analysis of transient-stability experiments. Starting from an existing equilibrium reconstruction from a past experiment, the workflow couples together the EFIT Grad-Shafranov solver [L. Lao et al., Fusion Sci. Technol. 48, 968 (2005)], the EPED model for the pedestal structure [P. B. Snyder et al., Phys. Plasmas 16, 056118 (2009)], and the NEO drift-kinetic-equation solver [E. A. Belli and J. Candy, Plasma Phys. Controlled Fusion 54, 015015 (2012)] (for bootstrap current calculations) in order to generate equilibria with self-consistent pedestal structures as the plasma shape and various scalar parameters (e.g., normalized β, pedestal density, and edge safety factor [q95]) are changed. These equilibria are then analyzed using automated M3D-C1 extended-magnetohydrodynamic modeling [S. C. Jardin et al., Comput. Sci. Discovery 5, 014002 (2012)] to compute the plasma response to three-dimensional magnetic perturbations. This workflow was created in conjunction with a DIII-D experiment examining the effect of triangularity on the 3D plasma response. Several versions of the workflow were developed, and the initial ones were used to help guide experimental planning (e.g., determining the plasma current necessary to maintain the constant edge safety factor in various shapes). Subsequent validation with the experimental results was then used to revise the workflow, ultimately resulting in the complete model presented here. We show that quantitative agreement was achieved between the M3D-C1 plasma response calculated for equilibria generated by the final workflow and equilibria reconstructed from experimental data. A comparison of results from earlier workflows is used to show the importance of properly matching certain experimental parameters in the generated equilibria, including the normalized β, pedestal density, and q95. On the other hand, the details of the pedestal current did not significantly impact the plasma response in these equilibria. A comparison to the experimentally measured plasma response shows mixed agreement, indicating that while the equilibria are predicted well, additional analysis tools may be needed. In conclusion, we note the implications that these results have for the success of future predict-first studies, particularly the need for scans of uncertain parameters and for close collaboration between experimentalists and theorists.},
doi = {10.1063/1.5025838},
journal = {Physics of Plasmas},
issn = {1070-664X},
number = 5,
volume = 25,
place = {United States},
year = {2018},
month = {5}
}

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Works referenced in this record:

Improved understanding of physics processes in pedestal structure, leading to improved predictive capability for ITER
journal, August 2013


Integrated Modeling of Tokamak Experiments with OMFIT
journal, January 2013


Magnetic-Flux Pumping in High-Performance, Stationary Plasmas with Tearing Modes
journal, January 2009


Reconstruction of current profile parameters and plasma shapes in tokamaks
journal, November 1985


Equilibrium analysis of current profiles in tokamaks
journal, June 1990


Predictive capability of MHD stability limits in high performance DIII-D discharges
journal, July 2002


H-mode pedestal scaling in DIII-D, ASDEX Upgrade, and JET
journal, May 2011

  • Beurskens, M. N. A.; Osborne, T. H.; Schneider, P. A.
  • Physics of Plasmas, Vol. 18, Issue 5
  • DOI: 10.1063/1.3593008

Connection between plasma response and resonant magnetic perturbation (RMP) edge localized mode (ELM) suppression in DIII-D
journal, September 2015


Comparisons of linear and nonlinear plasma response models for non-axisymmetric perturbations
journal, May 2013

  • Turnbull, A. D.; Ferraro, N. M.; Izzo, V. A.
  • Physics of Plasmas, Vol. 20, Issue 5
  • DOI: 10.1063/1.4805087

Effect of rotation zero-crossing on single-fluid plasma response to three-dimensional magnetic perturbations
journal, February 2017

  • Lyons, B. C.; Ferraro, N. M.; Paz-Soldan, C.
  • Plasma Physics and Controlled Fusion, Vol. 59, Issue 4
  • DOI: 10.1088/1361-6587/aa5860

Comparative investigation of ELM control based on toroidal modelling of plasma response to RMP fields
journal, May 2017

  • Liu, Yueqiang; Kirk, A.; Li, Li
  • Physics of Plasmas, Vol. 24, Issue 5
  • DOI: 10.1063/1.4978884

A first-principles predictive model of the pedestal height and width: development, testing and ITER optimization with the EPED model
journal, August 2011


Suppression of type-I ELMs with reduced RMP coil set on DIII-D
journal, February 2016


Contribution to the multi-machine pedestal scaling from the COMPASS tokamak
journal, April 2017


Theory and Simulation Basis for Magnetohydrodynamic Stability in DIII-D
journal, October 2005

  • Turnbull, A. D.; Brennan, D. P.; Chu, M. S.
  • Fusion Science and Technology, Vol. 48, Issue 2
  • DOI: 10.13182/FST05-A1046

Access to a New Plasma Edge State with High Density and Pressures using the Quiescent H Mode
journal, September 2014


Resonant Pedestal Pressure Reduction Induced by a Thermal Transport Enhancement due to Stochastic Magnetic Boundary Layers in High Temperature Plasmas
journal, October 2009


Stability and dynamics of the edge pedestal in the low collisionality regime: physics mechanisms for steady-state ELM-free operation
journal, August 2007


An upgrade of the magnetic diagnostic system of the DIII-D tokamak for non-axisymmetric measurements
journal, August 2014

  • King, J. D.; Strait, E. J.; Boivin, R. L.
  • Review of Scientific Instruments, Vol. 85, Issue 8
  • DOI: 10.1063/1.4891817

Edge localized modes and the pedestal: A model based on coupled peeling–ballooning modes
journal, May 2002

  • Snyder, P. B.; Wilson, H. R.; Ferron, J. R.
  • Physics of Plasmas, Vol. 9, Issue 5
  • DOI: 10.1063/1.1449463

Numerical analysis of the effects of normalized plasma pressure on RMP ELM suppression in DIII-D
journal, February 2010


Advances in the physics understanding of ELM suppression using resonant magnetic perturbations in DIII-D
journal, January 2015


MHD Equilibrium Reconstruction in the DIII-D Tokamak
journal, October 2005

  • Lao, L. L.; John, H. E. St.; Peng, Q.
  • Fusion Science and Technology, Vol. 48, Issue 2
  • DOI: 10.13182/FST48-968

Multi-region approach to free-boundary three-dimensional tokamak equilibria and resistive wall instabilities
journal, May 2016

  • Ferraro, N. M.; Jardin, S. C.; Lao, L. L.
  • Physics of Plasmas, Vol. 23, Issue 5
  • DOI: 10.1063/1.4948722

Self-consistent core-pedestal transport simulations with neural network accelerated models
journal, July 2017


A design retrospective of the DIII-D tokamak
journal, May 2002


ELM suppression in helium plasmas with 3D magnetic fields
journal, June 2017


Validation of the model for ELM suppression with 3D magnetic fields using low torque ITER baseline scenario discharges in DIII-D
journal, October 2017

  • Moyer, R. A.; Paz-Soldan, C.; Nazikian, R.
  • Physics of Plasmas, Vol. 24, Issue 10
  • DOI: 10.1063/1.5000276

Equilibrium drives of the low and high field side n   =  2 plasma response and impact on global confinement
journal, April 2016


RMP ELM suppression in DIII-D plasmas with ITER similar shapes and collisionalities
journal, January 2008


SOLPS analysis of neutral baffling for the design of a new diverter in DIII-D
journal, April 2017


Numerical studies of edge localized instabilities in tokamaks
journal, April 2002

  • Wilson, H. R.; Snyder, P. B.; Huysmans, G. T. A.
  • Physics of Plasmas, Vol. 9, Issue 4
  • DOI: 10.1063/1.1459058

Kinetic calculation of neoclassical transport including self-consistent electron and impurity dynamics
journal, July 2008


Suppression of edge localized mode crashes by multi-spectral non-axisymmetric fields in KSTAR
journal, October 2016


Modeling of 3D magnetic equilibrium effects on edge turbulence stability during RMP ELM suppression in tokamaks
journal, July 2017


Development and validation of a predictive model for the pedestal height
journal, May 2009

  • Snyder, P. B.; Groebner, R. J.; Leonard, A. W.
  • Physics of Plasmas, Vol. 16, Issue 5
  • DOI: 10.1063/1.3122146

Experimental studies of high-confinement mode plasma response to non-axisymmetric magnetic perturbations in ASDEX Upgrade
journal, November 2016


Multiple timescale calculations of sawteeth and other global macroscopic dynamics of tokamak plasmas
journal, January 2012


Super H-mode: theoretical prediction and initial observations of a new high performance regime for tokamak operation
journal, July 2015


Full linearized Fokker–Planck collisions in neoclassical transport simulations
journal, December 2011


Observation of a Multimode Plasma Response and its Relationship to Density Pumpout and Edge-Localized Mode Suppression
journal, March 2015


Pedestal Bifurcation and Resonant Field Penetration at the Threshold of Edge-Localized Mode Suppression in the DIII-D Tokamak
journal, March 2015


Edge stability of stationary ELM-suppressed regimes on DIII-D
journal, July 2008