Helical magnetorotational instability in a Taylor-Couette flow with strongly reduced Ekman pumping.

@article{Stefani2009HelicalMI,
  title={Helical magnetorotational instability in a Taylor-Couette flow with strongly reduced Ekman pumping.},
  author={Frank Stefani and Gunter Gerbeth and Thomas Gundrum and Rainer Hollerbach and Jānis Priede and G. R{\"u}diger and Jacek Szklarski},
  journal={Physical review. E, Statistical, nonlinear, and soft matter physics},
  year={2009},
  volume={80 6 Pt 2},
  pages={
          066303
        }
}
The magnetorotational instability (MRI) is thought to play a key role in the formation of stars and black holes by sustaining the turbulence in hydrodynamically stable Keplerian accretion disks. In previous experiments the MRI was observed in a liquid metal Taylor-Couette flow at moderate Reynolds numbers by applying a helical magnetic field. The observation of this helical MRI (HMRI) was interfered with a significant Ekman pumping driven by solid end caps that confined the instability only to… Expand
Transition to magnetorotational turbulence in Taylor–Couette flow with imposed azimuthal magnetic field
The magnetorotational instability (MRI) is thought to be a powerful source of turbulence and momentum transport in astrophysical accretion discs, but obtaining observational evidence of its operationExpand
Quasi-two-dimensional nonlinear evolution of helical magnetorotational instability in a magnetized Taylor-Couette flow
Magnetorotational instability (MRI) is one of the fundamental processes in astrophysics, driving angular momentum transport and mass accretion in a wide variety of cosmic objects. Despite muchExpand
Dynamics and transport of instabilities in magnetized quasi-Keplerian Taylor-Couette flows
The stability and transition to turbulence in canonical shear flows have since long been an outstanding scientific problem. One of the most exciting examples of shear flow is Keplerian motion of gasExpand
The weakly nonlinear magnetorotational instability in a global, cylindrical Taylor-Couette flow
We conduct a global, weakly nonlinear analysis of the magnetorotational instability (MRI) in a Taylor-Couette flow. This is a multiscale perturbative treatment of the nonideal, axisymmetric MRI nearExpand
The role of boundaries in the magnetorotational instability
In this paper, we investigate numerically the flow of an electrically conducting fluid in a cylindrical Taylor-Couette flow when an axial magnetic field is applied. To minimize Ekman recirculationExpand
Local instabilities in magnetized rotational flows: a short-wavelength approach
Abstract We perform a local stability analysis of rotational flows in the presence of a constant vertical magnetic field and an azimuthal magnetic field with a general radial dependence. EmployingExpand
Liquid metal experiments on the helical magnetorotational instability
The magnetorotational instability (MRI) plays an essential role in the formation of stars and black holes. By destabilizing hydrodynamically stable Keplerian flows, the MRI triggers turbulence andExpand
On the relation of standard and helical magnetorotational instability
The magnetorotational instability (MRI) plays a crucial role for cosmic structure formation by enabling turbulence in Keplerian disks which would be otherwise hydrodynamically stable. With particularExpand
Stability and instability of hydromagnetic Taylor-Couette flows
Decades ago S. Lundquist, S. Chandrasekhar, P.H. Roberts and R. J.~Tayler first posed questions about the stability of Taylor-Couette flows of conducting material under the influence of large-scaleExpand
A Unifying Picture of Helical and Azimuthal Magnetorotational Instability, and the Universal Significance of the Liu Limit
The magnetorotational instability (MRI) plays a key role for cosmic structure formation by triggering turbulence in the rotating flows of accretion disks that would be otherwise hydrodynamicallyExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 110 REFERENCES
Absolute versus convective helical magnetorotational instability in a Taylor-Couette flow.
  • J. Priede, G. Gerbeth
  • Physics, Medicine
  • Physical review. E, Statistical, nonlinear, and soft matter physics
  • 2009
TLDR
A detailed conventional linear stability analysis with respect to perturbations in the form of Fourier modes that corresponds to the convective instability which is not in general self-sustained is carried out. Expand
Helical magnetorotational instability in magnetized Taylor-Couette flow.
TLDR
It is shown that in the resistive limit, HMRI is a weakly destabilized inertial oscillation propagating in a unique direction along the axis, and features of HMRI that make it less attractive for experiments and for resistive astrophysical disks are reported. Expand
Inductionless magnetorotational instability in a Taylor-Couette flow with a helical magnetic field.
We consider the magnetorotational instability (MRI) of a hydrodynamically stable Taylor-Couette flow with a helical external magnetic field in the inductionless approximation defined by a zeroExpand
NOISE-SUSTAINED CONVECTIVE INSTABILITY IN A MAGNETIZED TAYLOR-COUETTE FLOW
The helical magnetorotational instability of the magnetized Taylor-Couette flow is studied numerically in a finite cylinder. A distant upstream insulating boundary is shown to stabilize theExpand
Ekman-Hartmann layer in a magnetohydrodynamic Taylor-Couette flow.
TLDR
It is shown that the end plates introduce, besides the well-known Ekman circulation, similar magnetic effects which arise for infinite, rotating plates, horizontally unbounded by any walls, and that the currents induced by the plates can give rise to instability for the considered parameters. Expand
Experimental evidence for magnetorotational instability in a Taylor-Couette flow under the influence of a helical magnetic field.
TLDR
Results of a Taylor-Couette experiment with the liquid metal alloy GaInSn are presented, showing evidence for the existence of the magnetorotational instability at Reynolds numbers of order 1000 and HartmannNumbers of order 10. Expand
Magnetized Ekman layer and Stewartson layer in a magnetized Taylor-Couette flow.
  • Wei Liu
  • Physics, Medicine
  • Physical review. E, Statistical, nonlinear, and soft matter physics
  • 2008
In this paper we present axisymmetric nonlinear simulations of magnetized Ekman and Stewartson layers in a magnetized Taylor-Couette flow with a centrifugally stable angular-momentum profile and withExpand
Nonlinear simulations of magnetic Taylor‐Couette flow with currentfree helical magnetic fields
Themagnetorotational instability (MRI) in cylindrical Taylor-Couette flow with external helical magnetic field is simulated for infinite and finite aspect ratios. We solve the MHD equations in theirExpand
Pseudo-magnetorotational instability in a Taylor-Dean flow between electrically connected cylinders.
  • J. Priede
  • Physics, Medicine
  • Physical review. E, Statistical, nonlinear, and soft matter physics
  • 2009
TLDR
There is no hydrodynamic stability limit defined in the terms of the critical ratio of rotation rates of inner and outer cylinders that would allow one to distinguish a hydrodynamically instability from the HMRI, and these effects can critically interfere with experimental as well as numerical determination of MRI. Expand
The stability of MHD Taylor‐Couette flow with current‐free spiral magnetic fields between conducting cylinders
We study the magnetorotational instability in cylindrical Taylor-Couette flow, with the (vertically unbounded) cylinders taken to be perfect conductors, and with externally imposed spiral magneticExpand
...
1
2
3
4
5
...