# Magnetic dynamo action at low magnetic Prandtl numbers.

@article{Malyshkin2010MagneticDA, title={Magnetic dynamo action at low magnetic Prandtl numbers.}, author={Leonid M. Malyshkin and Stanislav Boldyrev}, journal={Physical review letters}, year={2010}, volume={105 21}, pages={ 215002 } }

Amplification of magnetic field due to kinematic turbulent dynamo action is studied in the regime of small magnetic Prandtl numbers. Such a regime is relevant for planets and stars interiors, as well as for liquid-metal laboratory experiments. A comprehensive analysis based on the Kazantsev-Kraichnan model is reported, which establishes the dynamo threshold and the dynamo growth rates for varying kinetic helicity of turbulent fluctuations. It is proposed that in contrast with the case of large…

## 23 Citations

Small-scale dynamo at low magnetic Prandtl numbers.

- Physics, MedicinePhysical review. E, Statistical, nonlinear, and soft matter physics
- 2012

The small-scale dynamo can operate in the regime of low magnetic Prandtl numbers if the magnetic Reynolds number is large enough, and it is concluded that Rm_{crit} provides a stronger constraint in the limit of low Pm than it does for large Pm.

Turbulent magnetohydrodynamic dynamo action in a spherically bounded von Kármán flow at small magnetic Prandtl numbers

- Physics
- 2011

Turbulent magnetohydrodynamic (MHD) dynamo action in a spherically bounded electrically conducting flow is investigated numerically. A large-scale two-vortex flow driven by a constant body force is…

Turbulent magnetic field amplification from the smallest to the largest magnetic Prandtl numbers

- Physics
- 2013

The small-scale dynamo provides a highly efficient mechanism for the conversion of turbulent into magnetic energy. In astrophysical environments, such turbulence often occurs at high Mach numbers,…

The small-scale dynamo: breaking universality at high Mach numbers

- Physics
- 2013

The small-scale dynamo plays a substantial role in magnetizing the Universe under a large range of conditions, including subsonic turbulence at low Mach numbers, highly supersonic turbulence at high…

Traces of large-scale dynamo action in the kinematic stage

- Physics
- 2014

Using direct numerical simulations (DNS), we verify that in the kinematic regime, a turbulent helical dynamo grows in such a way that the magnetic energy spectrum remains to high-precision…

MAGNETIC DYNAMO ACTION IN RANDOM FLOWS WITH ZERO AND FINITE CORRELATION TIMES

- Physics
- 2011

Hydromagnetic dynamo theory provides the prevailing theoretical description for the origin of magnetic fields in the universe. Here, we consider the problem of kinematic, small-scale dynamo action…

Magnetorotational dynamo action in the shearing box

- Physics
- 2017

Magnetic dynamo action caused by the magnetorotational instability is studied in the shearing-box approximation with no imposed net magnetic flux. Consistent with recent studies, the dynamo action is…

Kinematic dynamo onset and magnetic field saturation in rotating spherical Couette and periodic box simulations

- Physics
- 2013

Magnetic fields are ubiquitous in the universe and can be found in celestial bodies, galaxies, stars including our Sun and planets like the Earth or Jupiter. Due to the fact that at least in the…

Turbulent magnetic Prandtl number in kinematic magnetohydrodynamic turbulence: two-loop approximation.

- Physics, MedicinePhysical review. E, Statistical, nonlinear, and soft matter physics
- 2011

The turbulent magnetic Prandtl number in the framework of the kinematic magnetohydrodynamic (MHD) turbulence, where the magnetic field behaves as a passive vector field advected by the stochastic…

A Study of the Dynamo Transition in a Self-consistent Nonlinear Dynamo Model

- Physics
- 2011

We develop a nonlinear dynamo model that couples the evolution of a large-scale magnetic field with the turbulent dynamics of a magnetofluid system in the small scale by electromotive force. Because…

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