Fluctuations, dissipation and turbulence in accretion discs

Details Fluctuations, dissipation and turbulence in accretion discs Fluctuations, dissipation and turbulence in accretion discs

Nov 1994

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994mnras.271..197b&link_type=abstract

Monthly Notices of the Royal Astronomical Society, Vol. 271, 197

Astronomy and Astrophysics

Astronomy

32

Scientific paper

In this paper, we relate dissipational processes in accretion discs to large-scale correlated fluctuations in the velocity and magnetic field components. The radial- azimuthal (R ) component of the correlation stress tensor for velocity and magnetic fluctuations is responsible for transport within the disc. Under steady conditions, the R component of the stress tensor scales with disc radius R and surface density as 1/(R312 ). This component of the stress tensor can also be related in a simple way to the local radiative flux density. This latter relation is observationally sensitive to surface irradiation, but the former scaling law is expected to be very robust. Both results are examples of fluctuation-dissipation relations for accretion discs. Eclipse mapping and Doppler tomography techniques in cataclysmic variables and X-ray binary systems may soon be able to test these types of theoretical predictions. Molecular viscosity serves only as an energy sink, not as a source of any turbulent transport, thermalizing the high-wavenumber end of the power spectrum. The same is true of microscopic resistivity with respect to magnetic field fluctuations. This implies that an explicit representation for the viscosity or resistivity is not essential for largescale numerical modelling of accretion disc turbulence. Key words: accretion, accretion discs - hydrodynamics - magnetic fields - turbulence.

Affiliated with

Also associated with

No associations

Rating

Fluctuations, dissipation and turbulence in accretion discs 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 Fluctuations, dissipation and turbulence in accretion discs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fluctuations, dissipation and turbulence in accretion discs will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-949406