English

von K\'arm\'an-Howarth equation for three-dimensional two-fluid plasmas

Plasma Physics 2016-06-22 v2 Fluid Dynamics

Abstract

We derive the von K\'arm\'an-Howarth equation for a full three dimensional incompressible two-fluid plasma. In the long-time limit and for very large Reynolds numbers we obtain the equivalent of the hydrodynamic "four-fifth" law. This exact law predicts the scaling of the third-order two-point correlation functions, and puts a strong constraint on the plasma turbulent dynamics. Finally, we derive a simple expression for the 4/5 law in terms of third-order structure functions, which is appropriate for comparison with in-situ measurements in the solar wind at different spatial ranges.

Keywords

Cite

@article{arxiv.1603.06794,
  title  = {von K\'arm\'an-Howarth equation for three-dimensional two-fluid plasmas},
  author = {Nahuel Andrés and Pablo Mininni and Pablo Dmitruk and Daniel Gómez},
  journal= {arXiv preprint arXiv:1603.06794},
  year   = {2016}
}