Nonlinear simulations of thermo-resistive tearing mode formalism of the density limit

Teng, Q.; Ferraro, N.; Gates, D. A.; White, R. B.

doi:10.1088/1741-4326/aad7c9

Title: Nonlinear simulations of thermo-resistive tearing mode formalism of the density limit

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Abstract

This work is an extension of the previous semi-analytical work (Teng et al 2016 Nucl. Fusion 56 106001), explaining the density limit with a thermo-resistive tearing mode model. The thermo-resistive island growth is calculated with a 3D MHD code M3D-C¹ (Jardin et al 2012 Comput. Sci. Discovery 5 014002). It is shown with nonlinear 3D MHD simulations that impurity radiation stimulates large magnetic islands at the density limit. The impact of thermal perturbations inside and outside of the island is explored. Inside the island, net cooling enhances the island growth and net heating suppresses its growth. Outside the island, thermal perturbations have a much smaller impact on the island growth. When the plasma density is increased towards the density limit, the island changes from being heated to being cooled and grows to a much larger island width. The convergence test of the simulations over the temporal and spatial grid is performed. In conclusion, the numerical model and the semi-analytical model are compared by calculating the Δ' terms, which are defined in the modified Rutherford equation, and good agreement is observed.

Authors:

Teng, Q. ^[1]; Ferraro, N. ^[1]; Gates, D. A. ^[1]; White, R. B. ^[1]

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

Publication Date:: Thu Aug 16 00:00:00 EDT 2018

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

Sponsoring Org.:: USDOE

OSTI Identifier:: 1466580

Grant/Contract Number:: AC02-09CH11466; SC0004125

Resource Type:: Accepted Manuscript

Journal Name:: Nuclear Fusion

Additional Journal Information:: Journal Volume: 58; Journal Issue: 10; Journal ID: ISSN 0029-5515

Publisher:: IOP Science

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; density limit; tearing mode; impurity radiation; MHD simulation

Citation Formats


                    Teng, Q., Ferraro, N., Gates, D. A., and White, R. B. Nonlinear simulations of thermo-resistive tearing mode formalism of the density limit.  United States: N. p., 2018. 
Web.  doi:10.1088/1741-4326/aad7c9.

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                    Teng, Q., Ferraro, N., Gates, D. A., & White, R. B. Nonlinear simulations of thermo-resistive tearing mode formalism of the density limit.  United States.  https://doi.org/10.1088/1741-4326/aad7c9

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                    Teng, Q., Ferraro, N., Gates, D. A., and White, R. B. Thu .  
"Nonlinear simulations of thermo-resistive tearing mode formalism of the density limit".  United States.  https://doi.org/10.1088/1741-4326/aad7c9.  https://www.osti.gov/servlets/purl/1466580.

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@article{osti_1466580,

  title        = {Nonlinear simulations of thermo-resistive tearing mode formalism of the density limit},

  author       = {Teng, Q. and Ferraro, N. and Gates, D. A. and White, R. B.},

  abstractNote = {This work is an extension of the previous semi-analytical work (Teng et al 2016 Nucl. Fusion 56 106001), explaining the density limit with a thermo-resistive tearing mode model. The thermo-resistive island growth is calculated with a 3D MHD code M3D-C1 (Jardin et al 2012 Comput. Sci. Discovery 5 014002). It is shown with nonlinear 3D MHD simulations that impurity radiation stimulates large magnetic islands at the density limit. The impact of thermal perturbations inside and outside of the island is explored. Inside the island, net cooling enhances the island growth and net heating suppresses its growth. Outside the island, thermal perturbations have a much smaller impact on the island growth. When the plasma density is increased towards the density limit, the island changes from being heated to being cooled and grows to a much larger island width. The convergence test of the simulations over the temporal and spatial grid is performed. In conclusion, the numerical model and the semi-analytical model are compared by calculating the Δ' terms, which are defined in the modified Rutherford equation, and good agreement is observed.},

  doi          = {10.1088/1741-4326/aad7c9},

  journal      = {Nuclear Fusion},

  number       = 10,

  volume       = 58,

  place        = {United States},

  year         = {Thu Aug 16 00:00:00 EDT 2018},

  month        = {Thu Aug 16 00:00:00 EDT 2018}

}

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