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Phase space scales of free energy dissipation in gradient-driven gyrokinetic turbulence

Published online by Cambridge University Press:  06 May 2014

D. R. Hatch*
Affiliation:
Institute for Fusion Studies, University of Texas at Austin, Austin, TX 78712, USA Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, D-85748 Garching, Germany
F. Jenko
Affiliation:
Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, D-85748 Garching, Germany Max-Planck/Princeton Center for Plasma Physics
V. Bratanov
Affiliation:
Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, D-85748 Garching, Germany
A. Bañón Navarro
Affiliation:
Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, D-85748 Garching, Germany
*
Email address for correspondence: [email protected]

Abstract

A reduced four-dimensional (integrated over perpendicular velocity) gyrokinetic model of slab ion temperature gradient-driven turbulence is used to study the phase-space scales of free energy dissipation in a turbulent kinetic system over a broad range of background gradients and collision frequencies. Parallel velocity is expressed in terms of Hermite polynomials, allowing for a detailed study of the scales of free energy dynamics over the four-dimensional phase space. A fully spectral code – the DNA code – that solves this system is described. Hermite free energy spectra are significantly steeper than would be expected linearly, causing collisional dissipation to peak at large scales in velocity space even for arbitrarily small collisionality. A key cause of the steep Hermite spectra is a critical balance – an equilibration of the parallel streaming time and the nonlinear correlation time – that extends to high Hermite number n. Although dissipation always peaks at large scales in all phase space dimensions, small-scale dissipation becomes important in an integrated sense when collisionality is low enough and/or nonlinear energy transfer is strong enough. Toroidal full-gyrokinetic simulations using the Gene code are used to verify results from the reduced model. Collision frequencies typically found in present-day experiments correspond to turbulence regimes slightly favoring large-scale dissipation, while turbulence in low-collisionality systems like ITER and space and astrophysical plasmas is expected to rely increasingly on small-scale dissipation mechanisms. This work is expected to inform gyrokinetic reduced modeling efforts like Large Eddy Simulation and gyrofluid techniques.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2014 

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References

REFERENCES

Armstrong, T. P., Harding, R. C., Knorr, G. and Montgomery, D. 1970 Methods in Comput. Phys. 9, 29.Google Scholar
Barnes, M., Parra, F. I. and Schekochihin, A. A. 2011 Phys. Rev. Lett. 107, 115003.Google Scholar
Bratanov, V., Jenko, F., Hatch, D. R. and Brunner, S. 2013 Phys. Plasmas 20, 022108.Google Scholar
Bratanov, V., Jenko, F., Hatch, D. R. and Wilczek, M. 2013 Phys. Rev. Lett. 111, 075001.Google Scholar
Cerri, S. S. 2013 private communication.Google Scholar
Doerk, H. 2013 Gyrokinetic simulation of microtearing turbulence. PhD thesis, Universität Ulm.CrossRefGoogle Scholar
Dorland, W. and Hammett, G. W. 1993 Phys. Fluids B 5, 812.CrossRefGoogle Scholar
Doyle, E. J.et al. 2007 Nucl. Fusion 47, S18.Google Scholar
Garbet, X., Idomura, Y., Villard, L. and Watanabe, T. H. 2010 Nucl. Fusion 50, 043002.CrossRefGoogle Scholar
Goldreich, P. and Sridhar, S. 1995 Astrophys. J. 438, 763.CrossRefGoogle Scholar
Görler, T. and Jenko, F. 2008 Phys. Plasmas 15, 102508.Google Scholar
Grant, F. C. and Feix, M. R. 1967 Phys. Fluids 10, 1356.Google Scholar
Hammett, G. W., Beer, M. A., Dorland, W., Cowley, S. C. and Smith, S. A. 1993 Plasma Phys. Control. Fusion 35, 973.CrossRefGoogle Scholar
Hammett, G. W., Dorland, W. and Perkins, F. W. 1992 Phys. Fluids B 4, 2052.Google Scholar
Hatch, D. R., del-Castillo-Negrete, D. and Terry, P. W. 2012 J. Comp. Phys. 231, 4234.Google Scholar
Hatch, D. R., Jenko, F., Navarro, A. B. and Bratanov, V. 2013 Phys. Rev. Lett. 111, 175001.Google Scholar
Howes, G. G.et al. 2006 Astrophys. J. 651, 590.CrossRefGoogle Scholar
Howes, G. G.et al. 2011a Phys. Rev. Lett. 107, 035004.Google Scholar
Hatch, D. R.et al. 2011b Phys. Rev. Lett. 106, 115003.CrossRefGoogle Scholar
Hatch, D. R.et al. 2011c Phys. Plasmas 18, 055706.Google Scholar
Helander, P., Beidler, C. D., Bird, T. M., Drevlak, M., Feng, Y., Hatzky, R., Jenko, F., Kleiber, R., Proll, J. H. E., Turkin, Y. and Xanthopoulos, P. 2013 Plasma Phys. Control. Fusion 54, 124009.Google Scholar
Jenko, F., Dorland, W., Kotschenreuther, M. and Rogers, B. N. 2000 Phys. Plasmas 7, 1904.CrossRefGoogle Scholar
Jenko, F., Told, D., Xanthopoulos, P., Merz, F. and Horton, L. D. 2009 Phys. Plasmas 16, 055901.CrossRefGoogle Scholar
Krommes, J. 2012 Annu. Rev. Fluid Mech. 44, 175.CrossRefGoogle Scholar
Landau, L. 1946 J. Phys. USSR 10, 25.Google Scholar
Lenard, A. and Bernstein, I. B. 1958 Phys. Rev. 112, 1456.CrossRefGoogle Scholar
Loureiro, N. F., Schekochihin, A. A. and Zocco, A. 2013 Phys. Rev. Lett. 111, 025002.Google Scholar
Makwana, K. D., Terry, P. W., Pueschel, M. J. and Hatch, D. R. 2014 Phys. Rev. Lett. 112 095002.CrossRefGoogle Scholar
Merz, F. 2009 Gyrokinetic simulation of multimode plasma turbulence, PhD thesis, Universität Münster.Google Scholar
Navarro, A. B., Teaca, B., Jenko, F., Hammett, G. W., Happel, T. and the ASDEX Upgrade Team, 2014 Phys. Plasmas 21, 032304CrossRefGoogle Scholar
Navarro, A. B.et al. 2011a Phys. Plasmas 18, 092303.Google Scholar
Navarro, A. B.et al. 2011b Phys. Rev. Lett. 106, 055001.Google Scholar
Numata, R., Dorland, W., Howes, G. G., Loureiro, N. F., Rogers, B. N. and Tatsuno, T. 2011 Phys. Plasmas 18, 112106.Google Scholar
Nunami, M., Watanabe, T. H., Sugama, H. and Tanaka, K. 2012 Phys. Plasmas 19, 042504.CrossRefGoogle Scholar
Parker, S. E.et al. 1994 Phys. Plasmas 1, 1461.Google Scholar
Petty, C. C. 2008 Phys. Plasmas 15, 080501.Google Scholar
Plunk, G., Cowley, S. C., Schekochihin, A. and Tatsuno, T. 2010 J. Fluid Mech. 664, 407.CrossRefGoogle Scholar
Plunk, G. G. and Tatsuno, T. 2011 Phys. Rev. Lett. 106, 165003.Google Scholar
Plunk, G. G., Tatsuno, T. and Dorland, W. 2012 New J. Phys. 14, 103030.CrossRefGoogle Scholar
Pueschel, M. J., Jenko, F., Told, D. and Büchner, J. 2011 Phys. Plasmas 18, 112102.Google Scholar
Schekochihin, A. A., Cowley, S. C., Dorland, W., Hammett, G. W., Howes, G. G., Plunk, G. G., Quataert, E. and Tatsuno, T. 2008 Plasma Phys. Control. Fusion 50, 124024.Google Scholar
Schekochihin, A. A.et al. 2009 Astrophys. J. 182, 310.Google Scholar
Scott, B. D., Kendl, A. and Ribeiro, T. 2010 Contrib. Plasma Phys. 50, 228.Google Scholar
Tatsuno, T.et al. 2009 Phys. Rev. Lett. 103, 015003.Google Scholar
Teaca, B.et al. 2012 Phys. Rev. Lett. 109, 235003.Google Scholar
TenBarge, J. M., Daughton, W., Karimabadi, H., Howes, G. G. and Dorland, W. 2014 Phys. Plasmas 21, 020708.Google Scholar
TenBarge, J. M. and Howes, G. G. 2012 Phys. Plasmas 19, 055901.Google Scholar
Terry, P. W.et al. 2006 Phys. Plasmas 13, 022307.Google Scholar
Wan, W.et al. 2012 Phys. Rev. Lett. 109, 185004.Google Scholar
Watanabe, T. H. and Sugama, H. 2004 Phys. Plasmas 11, 1476.Google Scholar
Watanabe, T. H. and Sugama, H. 2006 Nucl. Fusion 46, 24.CrossRefGoogle Scholar
Xanthopoulos, P., Merz, F., Görler, T., Jenko, F. 2007 Phys. Rev. Lett. 99, 035002.Google Scholar
Zocco, A. and Schekochihin, A. A. 2011 Phys. Plasmas 18, 102309.CrossRefGoogle Scholar