Turbulence appears everywhere in astro- and geo-physical flow
phenomena. Turbulence changes the configurations of the large-scale
structures of the density, velocity, vorticity, temperature, magnetic
field, etc., through the enhanced transport such as the eddy
viscosity, eddy diffusivity, abnormal resistivity. At the same time,
the inhomogeneous large-scale structures affect the properties of
turbulence through providing the sources of turbulence. In the
presence of rotation and/or magnetic field, which are /is ubiquitous
in astro- and geophysical phenomena, the mirror-symmetry of turbulence
is broken, then several helicities (kinetic, magnetic, current, cross
helicities) are generated there and play important roles in the
suppression of the turbulent transport as well. In this talk, after an
introduction of the basic notions, some illustrative examples of the
enhancement and suppression of turbulent transport are presented. The
examples include the large-scale flow generation by inhomogeneous
helicity and the global magnetic-field induction by cross helicity
(velocity–magnetic-field correlation).
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Дата события: понедельник, 13 Февраля, 2017 - 15:00 - 17:00
Доклад(ы):
Transport enhancement and suppression in inhomogeneous turbulence