Contrary to previous claims, the waves are shown to be transiently amplified disturbances launched by viscous boundary layers, rather than globally unstable magnetorotational modes. By accurately modeling viscous and magnetic boundaries in all directions, we reproduce the experimentally measured wave patterns and their amplitudes. We investigate numerically a traveling wave pattern observed in experimental magnetized Taylor-Couette flow at low magnetic Reynolds number. Traveling waves in a magnetized Taylor-Couette flow. The effect of turbulence suppression is dominating at a strong magnetic field, but before reaching the complete laminarization, we capture the appearance of the hairpin-like structures in the flow.
The results show that the mean radial induced electrical current, resulting from the interaction of axial magnetic field with the mean flow, leads to the transformation of the mean flow and the modification of the turbulent structure. Two sets of Reynolds numbers 40 with several Hartmann numbers varying from 0 to 120 are employed. Relevance of the present study is based on the similarity of flow characteristics at moderate and high magnetic field for the cases with periodic and end-wall conditions at the large flow aspect ratio, as proven in the earlier studies. We consider the case when the magnetic Reynolds number Rem ≪ 1, i.e., the influence of the induced magnetic field on the flow is negligible that is typical for industry and laboratory study of liquid metals.
The inner cylinder is rotating, and the outer one is fixed.
The effect of an axial homogeneous magnetic field on the turbulence in the Taylor-Couette flow confined between two infinitely long conducting cylinders is studied by the direct numerical simulation using a periodic boundary condition in the axial direction. Numerical simulation of turbulent Taylor-Couette flow between conducting cylinders in an axial magnetic field at low magnetic Reynolds number Our study of transition to and evolution of turbulence in the Taylor-Couette ferrofluidic flow system provides insights into the challenging problem of turbulence control. Our results imply that experimental investigation of turbulence may be feasible by using ferrofluids. A finding is that, as the magnetic field is increased, onset of turbulence can be determined accurately and reliably. This is established by extensive computational ferrohydrodynamics through a detailed investigation of transitions in the flow structure, and characterization of behaviors of physical quantities such as the energy, the wave number, and the angular momentum through the bifurcations. We find that, in the presence of a magnetic field transverse to the symmetry axis of the system, turbulence can occur at Reynolds numbers that are at least one order of magnitude smaller than those in conventional fluids. But can turbulence occur at low Reynolds numbers? Here we investigate the transition to turbulence in the classic Taylor-Couette system in which the rotating fluids are manufactured ferrofluids with magnetized nanoparticles embedded in liquid carriers. It is known that in classical fluids turbulence typically occurs at high Reynolds numbers. Transition to turbulence in Taylor-Couette ferrofluidic flowĪltmeyer, Sebastian Do, Younghae Lai, Ying-Cheng The orientation, axial distribution, onset, and tilting angle of these streaks are characterized. We study near-wall streaks that form herringbonelike patterns in Taylor-Couette turbulence and in counter-rotating Taylor-Couette turbulence through three-dimensional direct numerical simulations. Herringbone streaks in Taylor-Couette turbulence.
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