Reduced Four-Field System for Compressible Magnetohydrodynamic Turbulence in the Solar Wind and the Interstellar Medium

Statistics – Computation

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

Turbulent plasmas in the solar wind and the interstellar medium often contain a large directed magnetic field, and the plasma beta (beta ) is frequently of order unity. To describe the dynamics of these plasmas, we derive a system of reduced equations from the fully compressible MHD equations using the Alfven Mach number as a small parameter [G. P. Zank and W. H. Matthaeus, Phys. Fluids A 5, 257 (1993)]. These reduced equations constitute a closed system to leading order and involve four field variables: the magnetic flux, vorticity, pressure and parallel flow. The reduction of the fully compressible MHD equations to a four-field system offers significant computational advantages. If beta << 1, these equations reduced to the well-known Rosenbluth-Strauss equations (otherwise known as RMHD equations). However, for beta ~ 1, if the background equilibria have non-vanishing pressure gradients, the effect of compressibility is shown to enter at leading order. In such cases, our equations differ significantly from those of Zank and Matthaeus who claim that ``compressible effects ride parasitically on the back of the 2D incompressible flow field.'' We present numerical results involving current sheet formation, magnetic reconnection and intermittent turbulence that show clearly the dynamical differences between RMHD and four-field MHD. Implications for observations on pressure-balanced structures will be discussed. This work is supported by NSF and AFOSR.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Reduced Four-Field System for Compressible Magnetohydrodynamic Turbulence in the Solar Wind and the Interstellar Medium does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Reduced Four-Field System for Compressible Magnetohydrodynamic Turbulence in the Solar Wind and the Interstellar Medium, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Reduced Four-Field System for Compressible Magnetohydrodynamic Turbulence in the Solar Wind and the Interstellar Medium will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1352426

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.