 |
| Titel |
Multifractal two-scale Cantor set model for slow solar wind turbulence in the outer heliosphere during solar maximum |
| VerfasserIn |
W. M. Macek, A. Wawrzaszek |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1023-5809
|
| Digitales Dokument |
URL |
| Erschienen |
In: Nonlinear Processes in Geophysics ; 18, no. 3 ; Nr. 18, no. 3 (2011-05-12), S.287-294 |
| Datensatznummer |
250013918
|
| Publikation (Nr.) |
 copernicus.org/npg-18-287-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
| To quantify solar wind turbulence, we consider a generalized two-scale weighted Cantor set
with two different scales describing nonuniform distribution
of the kinetic energy flux between cascading eddies of various sizes.
We examine generalized dimensions
and the corresponding multifractal singularity spectrum
depending on one probability measure parameter and two rescaling parameters.
In particular, we analyse time series of velocities of
the slow speed streams of the solar wind measured in situ
by Voyager 2 spacecraft in the outer heliosphere during solar maximum
at various distances from the Sun: 10, 30, and 65 AU.
This allows us to look at the evolution of multifractal intermittent scaling
of the solar wind in the distant heliosphere.
Namely, it appears that while the degree of multifractality
for the solar wind during solar maximum is only weakly correlated
with the heliospheric distance,
but the multifractal spectrum could substantially be asymmetric
in a very distant heliosphere beyond the planetary orbits.
Therefore, one could expect that this scaling near the frontiers
of the heliosphere should rather be asymmetric.
It is worth noting that for the model with two different scaling parameters
a better agreement with the solar wind data is obtained,
especially for the negative index of the generalized dimensions.
Therefore we argue that there is a need to use a two-scale cascade model.
Hence we propose this model as a useful tool for analysis
of intermittent turbulence in various environments and
we hope that our general asymmetric multifractal model
could shed more light on the nature of turbulence. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|