Year: 2003
Type: article
Abstract: Chaotic flow is studied in a series of numerical magnetohydrodynamical simulations that use the shearing box formalism. This mimics important features of local accretion disc dynamics. The magnetorotational instability gives rise to flow turbulence, and quantitative chaos parameters, such as the largest Lyapunov exponent, can be measured. Linear growth rates appear in these exponents even when the flow is fully turbulent. The extreme sensitivity to initial conditions associated with chaotic flows has practical implications, the most important of which is that hundreds of orbital times are needed to extract a meaningful average for the stress. If the evolution time in a disc is less than this, the classical α formalism will break down.
Authors: Wayne F. Winters, Steven A. Balbus, John F. Hawley
Institution: University of Virginia
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W1974035738