The role of boundaries in the MagnetoRotational Instability

Abstract

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 recirculation due to vertical no-slip boundaries, two independently rotating rings are used at the vertical endcaps. This configuration reproduces setup used in laboratory experiments aiming to observe the MagnetoRotational Instability (MRI). Our 3D global simulations show that the nature of the bifurcation, the non-linear saturation, and the structure of axisymmetric MRI modes are significantly affected by the presence of boundaries. In addition, large scale non-axisymmetric modes are obtained when the applied field is sufficiently strong. We show that these modes are related to Kelvin-Helmoltz destabilization of a free Shercliff shear layer created by the combined action of the applied field and the rotating rings at the endcaps. Finally, we compare our numerical simulations to recent experimental results obtained in the Princeton MRI experiment.

11 pages, 9 figures

References in corpus (8)

• Hydrodynamic turbulence cannot transport angular momentum effectively in astrophysical disks
• Experimental observation and characterization of the magnetorotational instability
• Experimental evidence for magnetorotational instability in a helical magnetic field
• Helical Magnetorotational Instability in Magnetized Taylor-Couette Flow
• Observation of magnetocoriolis waves in a liquid metal Taylor-Couette experiment
• The Ekman-Hartmann layer in MHD Taylor-Couette flow
• Magnetized Ekman Layer and Stewartson Layer in a Magnetized Taylor-Couette Flow
• Numerical Study of the Magnetorotational Instability in Princeton MRI Experiment

Cited by in corpus (14)

• Numerical simulations of the Princeton magneto-rotational instability experiment with conducting axial boundaries
• Stability and instability of hydromagnetic Taylor-Couette flows
• Observation of axisymmetric standard magnetorotational instability in the laboratory
• Identification of a non-axisymmetric mode in laboratory experiments searching for standard magnetorotational instability
• Taylor-Couette flow for astrophysical purposes
• Instability in electromagnetically driven flows Part I
• Generalised quasi-linear approximation of the HMRI
• The weakly nonlinear magnetorotational instability in a global, cylindrical Taylor-Couette flow
• Instability in electromagnetically driven flows Part II
• Prospects for observing the magnetorotational instability in the Plasma Couette Experiment
• Quasi-two-dimensional nonlinear evolution of helical magnetorotational instability in a magnetized Taylor-Couette flow
• Shercliff layers in strongly magnetic cylindrical Taylor-Couette flow
• Laboratory modeling of MHD accretion disks
• Angular Momentum Transport by Keplerian Turbulence in Liquid Metals