Perturbative transport modeling of cold-pulse dynamics in Alcator C-Mod Ohmic plasmas

doi:10.1088/1741-4326/ab1575

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Title: Perturbative transport modeling of cold-pulse dynamics in Alcator C-Mod Ohmic plasmas

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Abstract

Perturbative transport experiments in magnetically confined plasmas have shown, for more than 20 years, that the injection of cold pulses at the plasma edge can trigger the increase of core temperature. Predictive heat transport simulations with the trapped gyro Landau fluid (TGLF) quasilinear transport model demonstrate that the increase of core temperature in some regimes, and lack thereof in other regimes, can be explained by a change in dominant linear micro-instability in Alcator C-Mod. The effect of density and plasma current on the cold pulse are well captured by TGLF, including the relative change in position of the temperature flex point as current density changes. Linear stability analysis of simulated density and current scans reveals a competition between trapped electron and ion temperature gradient modes as the main driver of the core transient response. Here these results further demonstrate that cold-pulse propagation and associated phenomenology in the cases studied are well explained within the local transport paradigm, without resorting to non-local effects.

Authors:

^[1]; White, A. E. ^[1];

^[1];

^[2]; Yuan, X. ^[2]; Staebler, G. M. ^[3];

^[1]; Angioni, C. ^[4]; Cao, N. M. ^[1];

^[1]; Fable, E. ^[4]; Greenwald, M. J. ^[1]; Hubbard, A. E. ^[1];

^[1]; Irby, J. H. ^[1]; Sciortino, F. ^[1]

MIT Plasma Science and Fusion Center, Cambridge, MA (United States)
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
General Atomics, San Diego, CA (United States)
Max Planck Institut für Plasmaphysik, Garching (Germany)

Publication Date:: 2019-05-02

Research Org.:: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1511148

Grant/Contract Number:: LCF/BQ/AN14/10340041; SC0014264; FC02-99ER54512

Resource Type:: Accepted Manuscript

Journal Name:: Nuclear Fusion

Additional Journal Information:: Journal Volume: 59; Journal Issue: 6; Journal ID: ISSN 0029-5515

Publisher:: IOP Science

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; cold-pulse; perturbative; TGLF; nonlocal

Citation Formats


                    Rodriguez-Fernandez, P., White, A. E., Howard, N. T., Grierson, B. A., Yuan, X., Staebler, G. M., Rice, J. E., Angioni, C., Cao, N. M., Creely, A. J., Fable, E., Greenwald, M. J., Hubbard, A. E., Hughes, J. W., Irby, J. H., and Sciortino, F. Perturbative transport modeling of cold-pulse dynamics in Alcator C-Mod Ohmic plasmas.  United States: N. p., 2019. 
        Web.  doi:10.1088/1741-4326/ab1575.

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                    Rodriguez-Fernandez, P., White, A. E., Howard, N. T., Grierson, B. A., Yuan, X., Staebler, G. M., Rice, J. E., Angioni, C., Cao, N. M., Creely, A. J., Fable, E., Greenwald, M. J., Hubbard, A. E., Hughes, J. W., Irby, J. H., & Sciortino, F. Perturbative transport modeling of cold-pulse dynamics in Alcator C-Mod Ohmic plasmas.  United States.  doi:10.1088/1741-4326/ab1575.

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                    Rodriguez-Fernandez, P., White, A. E., Howard, N. T., Grierson, B. A., Yuan, X., Staebler, G. M., Rice, J. E., Angioni, C., Cao, N. M., Creely, A. J., Fable, E., Greenwald, M. J., Hubbard, A. E., Hughes, J. W., Irby, J. H., and Sciortino, F. Thu .  
        "Perturbative transport modeling of cold-pulse dynamics in Alcator C-Mod Ohmic plasmas".  United States.  doi:10.1088/1741-4326/ab1575.

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@article{osti_1511148,

  title        = {Perturbative transport modeling of cold-pulse dynamics in Alcator C-Mod Ohmic plasmas},

  author       = {Rodriguez-Fernandez, P. and White, A. E. and Howard, N. T. and Grierson, B. A. and Yuan, X. and Staebler, G. M. and Rice, J. E. and Angioni, C. and Cao, N. M. and Creely, A. J. and Fable, E. and Greenwald, M. J. and Hubbard, A. E. and Hughes, J. W. and Irby, J. H. and Sciortino, F.},

  abstractNote = {Perturbative transport experiments in magnetically confined plasmas have shown, for more than 20 years, that the injection of cold pulses at the plasma edge can trigger the increase of core temperature. Predictive heat transport simulations with the trapped gyro Landau fluid (TGLF) quasilinear transport model demonstrate that the increase of core temperature in some regimes, and lack thereof in other regimes, can be explained by a change in dominant linear micro-instability in Alcator C-Mod. The effect of density and plasma current on the cold pulse are well captured by TGLF, including the relative change in position of the temperature flex point as current density changes. Linear stability analysis of simulated density and current scans reveals a competition between trapped electron and ion temperature gradient modes as the main driver of the core transient response. Here these results further demonstrate that cold-pulse propagation and associated phenomenology in the cases studied are well explained within the local transport paradigm, without resorting to non-local effects.},

  doi          = {10.1088/1741-4326/ab1575},

  journal      = {Nuclear Fusion},

  number       = 6,

  volume       = 59,

  place        = {United States},

  year         = {2019},

  month        = {5}

}

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