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Updated: Aug 9, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Spontaneous Core Rotation in Ferrofluid Pipe Flow
Alexei Krekhov1, Mark Shliomis2
1Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany.
Physical Review Letters
|April 4, 2017
Summary
Ferrofluid flow in a magnetic field transitions to a swirling pattern above critical conditions. This instability, driven by a swirl dynamo, features distinct core and annular flow phases and a notable flow rate increase.
Area of Science:
- Fluid dynamics
- Magnetohydrodynamics
- Non-Newtonian fluid behavior
Background:
- Ferrofluid behavior in axial magnetic fields is complex.
- Understanding flow transitions is crucial for applications.
Purpose of the Study:
- To analyze ferrofluid flow in a tube under an axial magnetic field.
- To investigate the transition to a swirling flow regime.
Main Methods:
- Analytical solutions were derived.
- Numerical simulations were performed.
Main Results:
- A transition from axial to swirling flow was predicted.
- A critical pressure drop and magnetic field strength induce swirl.
- The flow pattern exhibits two distinct phases: a rotating core and an axial annular layer, separated by a domain wall.
Conclusions:
- The study reveals a novel swirling instability in ferrofluids.
- The observed flow pattern and associated flow rate increase can aid in detecting this instability.
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