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Title: Gyrokinetic particle simulation of microturbulence for general magnetic geometry and experimental profiles

Abstract

Developments in gyrokinetic particle simulation enable the gyrokinetic toroidal code (GTC) to simulate turbulent transport in tokamaks with realistic equilibrium profiles and plasma geometry, which is a critical step in the code–experiment validation process. These new developments include numerical equilibrium representation using B-splines, a new Poisson solver based on finite difference using field-aligned mesh and magnetic flux coordinates, a new zonal flow solver for general geometry, and improvements on the conventional four-point gyroaverage with nonuniform background marker loading. The gyrokinetic Poisson equation is solved in the perpendicular plane instead of the poloidal plane. Exploiting these new features, GTC is able to simulate a typical DIII-D discharge with experimental magnetic geometry and profiles. The simulated turbulent heat diffusivity and its radial profile show good agreement with other gyrokinetic codes. The newly developed nonuniform loading method provides a modified radial transport profile to that of the conventional uniform loading method.

Authors:
 [1];  [2]; ;  [3];  [3];  [4];  [1]
  1. Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China)
  2. (United States)
  3. Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)
  4. (China)
Publication Date:
OSTI Identifier:
22408111
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COMPUTERIZED SIMULATION; DOUBLET-3 DEVICE; EXPERIMENTAL DATA; MAGNETIC FLUX COORDINATES; PARTICLES; PLASMA; POISSON EQUATION; TOROIDAL CONFIGURATION

Citation Formats

Xiao, Yong, E-mail: yxiao@zju.edu.cn, Department of Physics and Astronomy, University of California, Irvine, California 92697, Holod, Ihor, Wang, Zhixuan, Lin, Zhihong, Fusion Simulation Center, Peking University, Beijing 100871, and Zhang, Taige. Gyrokinetic particle simulation of microturbulence for general magnetic geometry and experimental profiles. United States: N. p., 2015. Web. doi:10.1063/1.4908275.
Xiao, Yong, E-mail: yxiao@zju.edu.cn, Department of Physics and Astronomy, University of California, Irvine, California 92697, Holod, Ihor, Wang, Zhixuan, Lin, Zhihong, Fusion Simulation Center, Peking University, Beijing 100871, & Zhang, Taige. Gyrokinetic particle simulation of microturbulence for general magnetic geometry and experimental profiles. United States. doi:10.1063/1.4908275.
Xiao, Yong, E-mail: yxiao@zju.edu.cn, Department of Physics and Astronomy, University of California, Irvine, California 92697, Holod, Ihor, Wang, Zhixuan, Lin, Zhihong, Fusion Simulation Center, Peking University, Beijing 100871, and Zhang, Taige. Sun . "Gyrokinetic particle simulation of microturbulence for general magnetic geometry and experimental profiles". United States. doi:10.1063/1.4908275.
@article{osti_22408111,
title = {Gyrokinetic particle simulation of microturbulence for general magnetic geometry and experimental profiles},
author = {Xiao, Yong, E-mail: yxiao@zju.edu.cn and Department of Physics and Astronomy, University of California, Irvine, California 92697 and Holod, Ihor and Wang, Zhixuan and Lin, Zhihong and Fusion Simulation Center, Peking University, Beijing 100871 and Zhang, Taige},
abstractNote = {Developments in gyrokinetic particle simulation enable the gyrokinetic toroidal code (GTC) to simulate turbulent transport in tokamaks with realistic equilibrium profiles and plasma geometry, which is a critical step in the code–experiment validation process. These new developments include numerical equilibrium representation using B-splines, a new Poisson solver based on finite difference using field-aligned mesh and magnetic flux coordinates, a new zonal flow solver for general geometry, and improvements on the conventional four-point gyroaverage with nonuniform background marker loading. The gyrokinetic Poisson equation is solved in the perpendicular plane instead of the poloidal plane. Exploiting these new features, GTC is able to simulate a typical DIII-D discharge with experimental magnetic geometry and profiles. The simulated turbulent heat diffusivity and its radial profile show good agreement with other gyrokinetic codes. The newly developed nonuniform loading method provides a modified radial transport profile to that of the conventional uniform loading method.},
doi = {10.1063/1.4908275},
journal = {Physics of Plasmas},
number = 2,
volume = 22,
place = {United States},
year = {Sun Feb 15 00:00:00 EST 2015},
month = {Sun Feb 15 00:00:00 EST 2015}
}
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