Turbulence and Self- Organized Criticality under finite driving- how they can look the same and how they are different

Details Turbulence and Self- Organized Criticality under finite driving- how they can look the same and how they are different Turbulence and Self- Organized Criticality under finite driving- how they can look the same and how they are different

Dec 2009

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009agufmsm43b1755r&link_type=abstract

American Geophysical Union, Fall Meeting 2009, abstract #SM43B-1755

Physics

Plasma Physics

[2788] Magnetospheric Physics / Magnetic Storms And Substorms, [4430] Nonlinear Geophysics / Complex Systems, [4480] Nonlinear Geophysics / Self-Organized Criticality, [7863] Space Plasma Physics / Turbulence

Scientific paper

The paradigm of Self- Organized Criticality (SOC) has found application in understanding scaling and bursty transport in driven, dissipative plasmas such as at the earth’s magnetosphere and the solar corona. Turbulence also has scaling and bursty transport as its observable signature so that the question naturally arises as to if, or how, these phenomena are related. SOC is a limiting process that occurs as the ratio of driving rate to dissipation rate is taken to zero, while idealized turbulence takes this ratio to infinity. We consider the more realistic scenario of finite driving rate. We demonstrate the difficulty of distinguishing SOC and turbulence under these conditions with a simple multifractal test timeseries, the p- model- which we show both exhibits multifractal scaling in its structure functions and finite range power law avalanche statistics. Similarity analysis identifies the control parameter RA which is analogous to the Reynolds Number RE of turbulence in that it relates to the number of excited degrees of freedom, that is, the range of spatio-temporal scales over which one finds scaling behaviour. However for avalanching systems the number of excited degrees of freedom is maximal at the zero driving rate, SOC limit, in the opposite sense to fluid turbulence. Practically, at finite RE or RA one observes scaling over a finite range which for turbulence, increases with RE and for SOC, decreases with RA, suggesting an observable trend to distinguish them. We use the BTW sandpile model to explore this idea and find that whilst avalanche distributions can, depending on the details of the driving, reflect this behaviour, power spectra do not and thus are not clear discriminators of an SOC state.

Affiliated with

Also associated with

No associations

Rating

Turbulence and Self- Organized Criticality under finite driving- how they can look the same and how they are different 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 Turbulence and Self- Organized Criticality under finite driving- how they can look the same and how they are different, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Turbulence and Self- Organized Criticality under finite driving- how they can look the same and how they are different will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1880638