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Title: Verification of 5D continuum gyrokinetic code COGENT: Studies of kinetic drift wave instability

COGENT (Continuum Gyrokinetic Edge New Technology) is a kinetic plasma simulation code that is being developed by the edge simulation laboratory (ESL) collaboration. The original version of the code has been developed in a 4D phase space (2D configuration space and 2D velocity space) to address kinetic plasma phenomena in a complex magnetic field geometry including the core, magnetic separatrix, and scrape-off layer regions. This paper is focused on extending the original 4D phase space to a 5D phase space (3D2V) to address full kinetic turbulences in a tokamak edge region. Here, we report on the current status of 5D COGENT, which presently operates in a shear-less, simple slab geometry. As a verification study, we use the problems of collision-less drift wave instability (universal instability) including its modification in the presence of collisional effects. The simulation model includes the gyrokinetic equations for ion and electron species coupled to the long-wavelength limit of the gyro-Poisson equation. Collisional effects are represented by the Krook collision model. Linear analytical results for the drift mode growth rate and real frequency are recovered, and the non-linear stage is modelled and analysed as well. In addition, extensive 5D runs have been performed to address the effectsmore » of the drift wave instability on blob/filamentary structures characteristic of a tokamak edge. Finally, a helical-shaped potential perturbation is observed to grow exponentially in time while spinning around the filament axis with electron drift frequency.« less
Authors:
 [1] ;  [2] ;  [3] ;  [4] ;  [2] ;  [3] ;  [2] ;  [1]
  1. Univ. of California, San Diego, CA (United States). Mechanical and Aerospace Engineering
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Fusion Energy Science Program
  3. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Fusion Energy Science Program. Center for Applied Scientific Computing
  4. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Report Number(s):
LLNL-JRNL-746119
Journal ID: ISSN 0863-1042; 930713
Grant/Contract Number:
AC52-07NA27344; FG02-04ER54739; SC0016548
Type:
Accepted Manuscript
Journal Name:
Contributions to Plasma Physics
Additional Journal Information:
Journal Volume: 58; Journal Issue: 6-8; Journal ID: ISSN 0863-1042
Publisher:
Wiley
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Univ. of California, San Diego, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; drift wave; edge; gyrokinetic; kinetic; plasma
OSTI Identifier:
1476212
Alternate Identifier(s):
OSTI ID: 1432721

Lee, Wonjae, Dorf, M. A., Dorr, M. R., Cohen, R. H., Rognlien, T. D., Hittinger, J. A. F., Umansky, M. V., and Krasheninnikov, S. I.. Verification of 5D continuum gyrokinetic code COGENT: Studies of kinetic drift wave instability. United States: N. p., Web. doi:10.1002/ctpp.201700161.
Lee, Wonjae, Dorf, M. A., Dorr, M. R., Cohen, R. H., Rognlien, T. D., Hittinger, J. A. F., Umansky, M. V., & Krasheninnikov, S. I.. Verification of 5D continuum gyrokinetic code COGENT: Studies of kinetic drift wave instability. United States. doi:10.1002/ctpp.201700161.
Lee, Wonjae, Dorf, M. A., Dorr, M. R., Cohen, R. H., Rognlien, T. D., Hittinger, J. A. F., Umansky, M. V., and Krasheninnikov, S. I.. 2018. "Verification of 5D continuum gyrokinetic code COGENT: Studies of kinetic drift wave instability". United States. doi:10.1002/ctpp.201700161.
@article{osti_1476212,
title = {Verification of 5D continuum gyrokinetic code COGENT: Studies of kinetic drift wave instability},
author = {Lee, Wonjae and Dorf, M. A. and Dorr, M. R. and Cohen, R. H. and Rognlien, T. D. and Hittinger, J. A. F. and Umansky, M. V. and Krasheninnikov, S. I.},
abstractNote = {COGENT (Continuum Gyrokinetic Edge New Technology) is a kinetic plasma simulation code that is being developed by the edge simulation laboratory (ESL) collaboration. The original version of the code has been developed in a 4D phase space (2D configuration space and 2D velocity space) to address kinetic plasma phenomena in a complex magnetic field geometry including the core, magnetic separatrix, and scrape-off layer regions. This paper is focused on extending the original 4D phase space to a 5D phase space (3D2V) to address full kinetic turbulences in a tokamak edge region. Here, we report on the current status of 5D COGENT, which presently operates in a shear-less, simple slab geometry. As a verification study, we use the problems of collision-less drift wave instability (universal instability) including its modification in the presence of collisional effects. The simulation model includes the gyrokinetic equations for ion and electron species coupled to the long-wavelength limit of the gyro-Poisson equation. Collisional effects are represented by the Krook collision model. Linear analytical results for the drift mode growth rate and real frequency are recovered, and the non-linear stage is modelled and analysed as well. In addition, extensive 5D runs have been performed to address the effects of the drift wave instability on blob/filamentary structures characteristic of a tokamak edge. Finally, a helical-shaped potential perturbation is observed to grow exponentially in time while spinning around the filament axis with electron drift frequency.},
doi = {10.1002/ctpp.201700161},
journal = {Contributions to Plasma Physics},
number = 6-8,
volume = 58,
place = {United States},
year = {2018},
month = {4}
}