Considering Fluctuation Energy as a Measure of Gyrokinetic Turbulence

Abstract

In gyrokinetic theory there are two quadratic measures of fluctuation energy, left invariant under nonlinear interactions, that constrain the turbulence. The recent work of Plunk and Tatsuno [Phys. Rev. Lett. 106, 165003 (2011)] reported on the novel consequences that this constraint has on the direction and locality of spectral energy transfer. This paper builds on that work. We provide detailed analysis in support of the results of Plunk and Tatsuno but also significantly broaden the scope and use additional methods to address the problem of energy transfer. The perspective taken here is that the fluctuation energies are not merely formal invariants of an idealized model (two-dimensional gyrokinetics) but are general measures of gyrokinetic turbulence, i.e. quantities that can be used to predict the behavior of the turbulence. Though many open questions remain, this paper collects evidence in favor of this perspective by demonstrating in several contexts that constrained spectral energy transfer governs the dynamics.

arXiv commentFinal version as published. Some cosmetic changes and update of references

References in corpus (14)

• Astrophysical gyrokinetics: kinetic and fluid turbulent cascades in magnetized weakly collisional plasmas
• A Model of Turbulence in Magnetized Plasmas: Implications for the Dissipation Range in the Solar Wind
• Nonlinear phase mixing and phase-space cascade of entropy in gyrokinetic plasma turbulence
• Critically balanced ion temperature gradient turbulence in fusion plasmas
• Gyrokinetic turbulence: a nonlinear route to dissipation through phase space
• AstroGK: Astrophysical Gyrokinetics Code
• Phase-space Lagrangian derivation of electrostatic gyrokinetics in general geometry
• Nonlinear entropy transfer via zonal flows in gyrokinetic plasma turbulence
• Two-dimensional gyrokinetic turbulence
• Inertial range turbulence in kinetic plasmas
• Free energy cascade in gyrokinetic turbulence
• Energy transfer and dual cascade in kinetic magnetized plasma turbulence
• Exact Energy Conservation Laws for Full and Truncated Nonlinear Gyrokinetic Equations
• Gyrokinetic simulation of entropy cascade in two-dimensional electrostatic turbulence

Cited by in corpus (7)

• Collisionless microinstabilities in stellarators I - analytical theory of trapped-particle modes
• Understanding nonlinear saturation in zonal-flow-dominated ion temperature gradient turbulence
• Nonlinear growth of zonal flows by secondary instability in general magnetic geometry
• On the nonlinear stability of a quasi-two-dimensional drift kinetic model for ion temperature gradient turbulence
• Freely decaying turbulence in two-dimensional electrostatic gyrokinetics
• On the scaling of ion and electron temperature gradient driven turbulence in slab geometry
• Predicting the Dimits shift through reduced mode tertiary instability analysis in a strongly driven gyrokinetic fluid limit