Abstract

We investigate the dynamics of ferrofluidic wavy vortex flows in the counter-rotating Taylor-Couette system, with a focus on wavy flows with a mixture of the dominant azimuthal modes. Without external magnetic field flows are stable and pro-grade with respect to the rotation of the inner cylinder. More complex behaviors can arise when an axial or a transverse magnetic field is applied. Depending on the direction and strength of the field, multi-stable wavy states and bifurcations can occur. We uncover the phenomenon of flow pattern reversal as the strength of the magnetic field is increased through a critical value. In between the regimes of pro-grade and retrograde flow rotations, standing waves with zero angular velocities can emerge. A striking finding is that, under a transverse magnetic field, a second reversal in the flow pattern direction can occur, where the flow pattern evolves into pro-grade rotation again from a retrograde state. Flow reversal is relevant to intriguing phenomena in nature such as geomagnetic reversal. Our results suggest that, in ferrofluids, flow pattern reversal can be induced by varying a magnetic field in a controlled manner, which can be realized in laboratory experiments with potential applications in the development of modern fluid devices.

Original languageEnglish (US)
Article number18589
JournalScientific Reports
Volume5
DOIs
StatePublished - Dec 21 2015

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flow distribution
grade
magnetic fields
ferrofluids
angular velocity
standing waves
counters
vortices
fluids

ASJC Scopus subject areas

  • General

Cite this

Magnetic field induced flow pattern reversal in a ferrofluidic Taylor-Couette system. / Altmeyer, Sebastian; Do, Younghae; Lai, Ying-Cheng.

In: Scientific Reports, Vol. 5, 18589, 21.12.2015.

Research output: Contribution to journalArticle

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