• Navier-Stokes
• les
• kinetic
• dissipation
• cascade
• plasma
• simulations
• turbulence

The physics of turbulence in incompressible hydrodynamics follows a clear scheme: energy is injected at large scales, via non linear processes it cascades to smaller scales throughout the so called inertial range and it is eventually dissipated by molecular viscosity, which stems from inter-particles collisions.

In collisionless plasmas, even in the simplest limit of incompressible turbulence, the picture is much more complex. The presence of a mean magnetic field introduces characteristic scales of charged particles (first of all the electron and ion Larmor radius) that break the property of scale invariance. As a result, the range of scales is split into three different and interconnected ranges corresponding to three regimes in which the physics and therefore the energy transfer properties vary greatly. In addition, because of the absence of collisions, we face the difficulty of modeling dissipation and heating. On top of all the aforementioned complexity we have kinetic effects (Landau damping, cyclotron resonances, instabilities,...) at play in the plasma which impact the full dynamic and the cross scale energy transfer.

The central idea of this work is to study dissipation in kinetic collisionless plasma and in particular try to quantify the dissipation rate via the turbulent cascade rate and using an innovative spatial filtering method that allows us to quantify local energization.