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| Titel |
Reconnection studies under different types of turbulence driving |
| VerfasserIn |
G. Kowal, A. Lazarian, E. T. Vishniac, K. Otmianowska-Mazur |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1023-5809
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| Digitales Dokument |
URL |
| Erschienen |
In: Nonlinear Processes in Geophysics ; 19, no. 2 ; Nr. 19, no. 2 (2012-04-18), S.297-314 |
| Datensatznummer |
250014197
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| Publikation (Nr.) |
 copernicus.org/npg-19-297-2012.pdf |
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| Zusammenfassung |
| We study a model of fast magnetic reconnection in the presence of weak
turbulence proposed by Lazarian and Vishniac (1999) using three-dimensional direct
numerical simulations. The model has been already successfully tested in
Kowal et al. (2009) confirming the dependencies of the reconnection speed Vrec
on the turbulence injection power Pinj and the injection scale linj
expressed by a constraint Vrec ~ Pinj1/2linj3/4and no
observed dependency on Ohmic resistivity. In Kowal et al. (2009), in order to drive
turbulence, we injected velocity fluctuations in Fourier space with frequencies
concentrated around kinj = 1/linj, as described in Alvelius (1999). In
this paper, we extend our previous studies by comparing fast magnetic
reconnection under different mechanisms of turbulence injection by introducing a
new way of turbulence driving. The new method injects velocity or magnetic
eddies with a specified amplitude and scale in random locations directly in real
space. We provide exact relations between the eddy parameters and turbulent
power and injection scale. We performed simulations with new forcing in order
to study turbulent power and injection scale dependencies. The results show no
discrepancy between models with two different methods of turbulence driving
exposing the same scalings in both cases. This is in agreement with the
Lazarian and Vishniac (1999) predictions. In addition, we performed a series of
models with varying viscosity ν. Although Lazarian and Vishniac (1999) do
not provide any prediction for this dependence, we report a weak relation
between the reconnection speed with viscosity, Vrec ~ ν−1/4. |
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