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Title: Statistical analysis of fluctuations and noise-driven transport in particle-in-cell simulations of plasma turbulence

Abstract

The problem of discrete particle noise has been studied based on direct fluctuation measurements from gyrokinetic particle-in-cell simulations of stable plasmas. From the statistical analysis of electrostatic potential time evolution, the space-time correlation function has been measured. Fluctuation spectra have been constructed and analyzed in detail. Noise-driven transport is calculated using the quasilinear expression for the diffusion coefficient and the obtained noise spectrum. The theoretical value of electron heat conductivity shows good agreement with that measured in the simulation. It has been shown that for the realistic parameters in actual turbulence simulations, the noise-driven transport depends linearly on the entropy of the system. This study makes it possible to estimate and subtract the noise contribution to the total transport during turbulence simulations.

Authors:
;  [1]
  1. Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)
Publication Date:
OSTI Identifier:
20974878
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 3; Other Information: DOI: 10.1063/1.2673002; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CORRELATION FUNCTIONS; ENTROPY; FLUCTUATIONS; NOISE; PLASMA; PLASMA SIMULATION; POTENTIALS; SPACE-TIME; THERMODYNAMICS

Citation Formats

Holod, I., and Lin, Z.. Statistical analysis of fluctuations and noise-driven transport in particle-in-cell simulations of plasma turbulence. United States: N. p., 2007. Web. doi:10.1063/1.2673002.
Holod, I., & Lin, Z.. Statistical analysis of fluctuations and noise-driven transport in particle-in-cell simulations of plasma turbulence. United States. doi:10.1063/1.2673002.
Holod, I., and Lin, Z.. Thu . "Statistical analysis of fluctuations and noise-driven transport in particle-in-cell simulations of plasma turbulence". United States. doi:10.1063/1.2673002.
@article{osti_20974878,
title = {Statistical analysis of fluctuations and noise-driven transport in particle-in-cell simulations of plasma turbulence},
author = {Holod, I. and Lin, Z.},
abstractNote = {The problem of discrete particle noise has been studied based on direct fluctuation measurements from gyrokinetic particle-in-cell simulations of stable plasmas. From the statistical analysis of electrostatic potential time evolution, the space-time correlation function has been measured. Fluctuation spectra have been constructed and analyzed in detail. Noise-driven transport is calculated using the quasilinear expression for the diffusion coefficient and the obtained noise spectrum. The theoretical value of electron heat conductivity shows good agreement with that measured in the simulation. It has been shown that for the realistic parameters in actual turbulence simulations, the noise-driven transport depends linearly on the entropy of the system. This study makes it possible to estimate and subtract the noise contribution to the total transport during turbulence simulations.},
doi = {10.1063/1.2673002},
journal = {Physics of Plasmas},
number = 3,
volume = 14,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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