Plasma turbulence: ELMFIRE
To elucidate the physics behind fundamental transport processes in tokamak plasmas the gyrokinetic ELMFIRE code has been developed within the Fusion and Plasma Physics group and VTT Technical Research Centre of Finland.
Group: Timo Kiviniemi, Laurent Chôné, Susan Leerink
Group: Timo Kiviniemi, Laurent Chôné, Susan Leerink
Although regimes exist in current tokamak experiments, in which the plasma is found stable to global MHD modes, the plasma is always in a state of thermodynamic quasi-equilibrium with an abundance of free energy for driving more benign instabilities. These instabilities reduce the confinement time through convection dominated transport (turbulence).
Confinement modes, which are observed to suppress this micro-turbulence (such as the high confinement mode, or H-mode) have been found experimentally. On the other hand, theoretical models of such confinement mode transitions and related phenomena are still incomplete.
The computational algorithm of the gyrokinetic full-f model ELMFIRE is a Lagrangian explicit/implicit predictor-corrector solver for the reduced Boltzmann equation in a magnetized plasma. For example, it has been applied to numerically investigate on transport phenomena in the tokamak, such as ion temperature gradient and trapped electron modes, zonal flows, and neoclassical feedback to turbulence.
- full-radius simulations of axisymmetric plasmas with limiter scrape-off layer
- full fe, full fi → allows significant changes in plasma profiles during simulation
- drift-kinetic electrons and gyrokinetic ions – one impurity species can be included
- circular concentric magnetic background
- 3D electrostatic potential from nonlinear polarization and electron parallel nonlinearity via direct implicit method
- collisions are evaluated using a binary collision model → neo-classical physics included
- guiding centre equations and simulation grid in straight-field-line coordinates
- analytic neutral model
- radiation losses can be included
- temperature can be maintained or heated up with background collisions
- benchmarked against Cyclone base case, neoclassical properties, and FT-2 experiments
- Fluctuations of electron density in gyrokinetic simulation of tokamak turbulence using Elmfire (poloidal cut) including scrape-off-layer (Youtube)
- CRESTA: Modelling for Large Engineering Projects (Elmfire part starts at 4.08)
- Elmfire simulation of density fluctuation in FT-2 tokamak (Youtube)
- Elmfire simulation of Ohmic FT-2 discharge (Youtube)
- Paavo Niskala: Simulations of turbulence-flow interplay in tokamak plasmas - Gyrokinetic studies of isotope effect on turbulent transport and flows in Ohmic discharges (2018)
- Tuomas Korpilo: Global Gyrokinetic Particle Simulations of Circular Limiter Tokamak Plasmas (2017)
- Salomon Janhunen: Gyrokinetic particle simulation for thermonuclear plasma turbulence studies in magnetic confinement (2013)
- Susan Leerink: Gyrokinetic full-f transport simulations of ohmic FT-2 tokamak discharge (2012)
- Niskala, P.; Gurchenko, A. D.; Gusakov, E. Z.; Altukhov, A. B.; Esipov, L. A.; Chone, L.; Kiviniemi, T. P.; Leerink, S., Neoclassical and turbulent E x B flows in flux-driven gyrokinetic simulations of Ohmic tokamak plasmas, Nuclear Fusion 58 (2018) 112006.
- Kiviniemi, T. P.; Niskala, P.; Askinazi, L. G.; Belokurov, A. A.; Chone, L.; Gurchenko, A. D.; Gusakov, E. Z.; Korpilo, T.; Lebedev, S. V.; Leerink, S.; Rochford, R.; Tukachinsky, A. S., Gyrokinetic simulation of transport reduction by pellet injection in TUMAN-3M tokamak, Plasma Physics and Controlled Fusion, 60 (2018) 085010
- P. Niskala, A.D. Gurchenko, E.Z. Gusakov, A.B. Altukhov, L.A. Esipov, M.Yu. Kantor, T.P. Kiviniemi, D. Kouprienko, T. Korpilo, S.I. Lashkul, S. Leerink, A.A. Perevalov and R. Rochford, Gyrokinetic characterization of the isotope effect in turbulent transport at the FT-2 tokamak, Plasma Physics and Controlled Fusion 59 (2017) 044010.
- T. Korpilo, T.P. Kiviniemi, S. Leerink, P. Niskala and R. Rochford, "Gyrokinetic Simulations of the Tokamak Plasma Edge in Circular Limiter Configuration". Contributions to Plasma Physics 56 (2016) 549.
- T. Korpilo, A.D. Gurchenko, E.Z. Gusakov, J.A. Heikkinen, S.J. Janhunen, T.P. Kiviniemi, S. Leerink, P. Niskala and A.A. Perevalov, "Gyrokinetic full-torus simulations of ohmic tokamak plasmas in circular limiter configuration". Computer Physics Communications 203 (2016) 128.
- A. Gurchenko, E. Gusakov, P. Niskala, A. Altukhov, L. Esipov, T. Kiviniemi, T. Korpilo, D. Kouprienko, S. Lashkul, S. Leerink, A. Perevalov and M. Irzak, ”The isotope effect in turbulent transport control by GAMs. Observation and gyrokinetic modeling.” Plasma Physics and Controlled Fusion 58 (2016) 044002.
- P. Niskala, T.P. Kiviniemi, S. Leerink and T. Korpilo, ”Gyrokinetic simulations of interplay between geodesic acoustic modes and trapped electron mode turbulence”. Nuclear Fusion 55 (2015) 073012.
- A.D. Gurchenko, E.Z. Gusakov, P. Niskala, A.B. Altukhov, L.A. Esipov, T.P. Kiviniemi, D.V. Kouprienko, M.Yu. Kantor, S.I. Lashkul, S. Leerink, A.A. Perevalov and T. Korpilo, ”Turbulence and anomalous tokamak transport control by Geodesic Acoustic Mode”. European Physical Letters 110 (2015) 55001.
- T.P. Kiviniemi, S. Leerink, P. Niskala, J.A. Heikkinen, T. Korpilo and S. Janhunen, "Comparison of gyrokinetic simulation of parallel plasma conductivity to analytical models". Plasma Physics and Controlled Fusion 56 (2014) 075009.
- T. Korpilo, J.A. Heikkinen, S.J. Janhunen, T.P. Kiviniemi, S. Leerink and F. Ogando, ”Numerically stable method for kinetic electrons in gyrokinetic particle-in-cell simulation of toroidal plasmas”. Journal of Computational Physics 239 (2013) 22.
- E.Z. Gusakov, A.B. Altukhov, V.V. Bulanin, A.D. Gurchenko, J.A. Heikkinen, S.J. Janhunen, S. Leerink, L.A. Esipov, M. Yu Kantor, T.P. Kiviniemi, T. Korpilo, D.V. Kouprienko, S.I. Lashkul, A.V. Petrov and N.V. Teplova, “Anomalous transport and multi-scale drift turbulence dynamics in tokamak ohmic discharge as measured by high resolution diagnostics and modeled by full-f gyrokinetic code”. Plasma Physics and Controlled Fusion 55 (2013) 124034.
- S. Leerink, V.V. Bulanin, A.D. Gurchenko, E.Z. Gusakov, J.A. Heikkinen, S.J. Janhunen, S.I. Lashkul, A.B. Altukhov, L.A. Esipov, M. Yu. Kantor, T.P. Kiviniemi, T. Korpilo, D.V. Kuprienko and A.V. Petrov, “Multiscale Investigations of Drift-Wave Turbulence and Plasma Flows: Measurements and Total-Distribution-Function Gyrokinetic Simulations”. Physical Review Letters 109 (2012) 16500.
- J.A. Heikkinen, T. Korpilo, S.J. Janhunen, T.P. Kiviniemi, S. Leerink and F. Ogando, “Interpolation for momentum conservation in 3D toroidal gyrokinetic particle simulation of plasmas”. Computer Physics Communications 183 (2012) 1719.
- T.P. Kiviniemi, S. Leerink, J.A. Heikkinen, S.J. Janhunen and T. Korpilo, “Gyrokinetic Simulations of the Edge Pedestal in the TEXTOR Tokamak”, Contributions to Plasma Physics 52 (2012) 406.
- J.A. Heikkinen, M. Nora, Physics of Plasmas, “Gyrokinetic equations and full f solution method based on Dirac’s constrained Hamiltonian and inverse Kruskal iteration”. Physics of Plasmas 18 (2011) 022310.
- S. Janhunen, J.A. Heikkinen, T. Korpilo, S. Leerink, M. Nora and F. Ogando, “Recent advances in gyrokinetic full-f particle simulation of medium sized tokamaks with ELMFIRE”. Contributions to Plasma Physics 50 (2010) 252.
- S. Leerink, V.V. Bulanin, E.Z. Gusakov, J.A. Heikkinen, S.J. Janhunen, T.P. Kiviniemi, T. Korpilo, M. Nora and F. Ogando, “Synthetic Doppler Reflectometer Diagnostic for nonlinear global gyrokinetic simulations”. Contributions to Plasma Physics 50 (2010) 242.
- J.A. Heikkinen, S.J. Janhunen, T.P. Kiviniemi and F. Ogando, “Full f gyrokinetic method for particle simulation of tokamak transport”. Journal of Computational Physics 227 (2008) 5582.
- G. Falchetto, B. Scott, P. Angelino, A. Bottino, T. Dannert, V. Grandgirard, S.Janhunen, F.Jenko, S. Jolliet, A. Kendl, B. McMillan, V. Naulin, A.H. Nielsen, M. Ottaviani and A. Peeters, “The European turbulence code benchmarking effort: turbulence driven by thermal gradients in magnetically confined plasmas”. Plasma Physics and Controlled Fusion 50 (2008) 1-12.
- S.J. Janhunen, F. Ogando, J.A. Heikkinen, T.P. Kiviniemi and S. Leerink, “Collisional dynamics of Erin turbulent plasmas in toroidal geometry”. Nuclear Fusion 47 (2007) 875.