Magnetic field generation by coherent turbulence structures

Magnetic field generation by coherent turbulence structures

It is thought that the small-scale magnetic fields observed in accretion discs, galaxies and galactic clusters are generated by a dynamo process in which the turbulent plasma amplifies small initial magnetic fluctuations. Numerical simulations of turbulence have revealed that turbulence consists of filamentlike vortex structures superimposed on an incoherent background, which carry a considerab...

Coherent structures in wall-bounded turbulence.

The inherent difficulty of understanding turbulence has led to researchers attacking the topic in many different ways over the years of turbulence research. Some approaches have been more successful than others, but most only deal with part of the problem. One approach that has seen reasonable success (or at least popularity) is that of attempting to deconstruct the complex and disorganised tur...

Turbulence and the Dynamics of Coherent Structures

Coherent structures in electrostatic interchange mode turbulence

Generation of magnetic field by combined action of turbulence and shear.

The feasibility of a mean-field dynamo in nonhelical turbulence with a superimposed linear shear is studied numerically in elongated shearing boxes. Exponential growth of the magnetic field at scales much larger than the outer scale of the turbulence is found. The characteristic scale of the field is lB proportional S(-1/2) and the growth rate is gamma proportional S, where S is the shearing ra...