@InProceedings{RempelMiraChia:2016:SuAmSy,
author = "Rempel, Erico Luiz and Miranda, Rodrigo and Chian, Abraham Chian
Long",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and
{Universidade de Bras{\'{\i}}lia (UnB)} and {Instituto
Tecnol{\'o}gico de Aeron{\'a}utica (ITA)}",
title = "Supertransient and amplitude-phase synchronization in a
astrophysical shear flows",
year = "2016",
organization = "International Conference on Nonlinear Science and Complexity, 6.",
keywords = "On-off intermittency, amplitude-phase synchronization, accretion
discs, magnetohydrodynamics, turbulence.",
abstract = "We study the development of coherent structures in local
simulations of the magnetorotational instability in accretion
discs in regimes of onoff intermittency. In Chian et al. (2010),
we have shown that the laminar and bursty states due to the onoff
spatiotemporal intermittency in a onedimensional model of
non-linear waves correspond, respectively, to non- attracting
coherent structures with higher and lower degrees of
amplitude-phase synchronization. In this paper, we extend these
results to a three-dimensional model of magnetized Keplerian shear
flows. Keeping the kinetic Reynolds number and the magnetic
Prandtl number fixed, we investigate two different intermittent
regimes by varying the plasma beta parameter. The first regime is
characterized by turbulent patterns interrupted by the recurrent
emergence of a large-scale coherent structure known as two-channel
flow, where the state of the system can be described by a single
Fourier mode. The second regime is dominated by the turbulence
with sporadic emergence of coherent structures with shapes that
are reminiscent of a perturbed channel flow. By computing the
Fourier power and phase spectral entropies in three dimensions, we
show that the large-scale coherent structures are characterized by
a high degree of amplitude-phase synchronization.",
conference-location = "S{\~a}o Jos{\'e} dos Campos, SP",
conference-year = "16-20 May",
urlaccessdate = "04 jun. 2024"
}