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Updated: May 18, 2026
07:33
Quantifying Mixing using Magnetic Resonance Imaging
Published on: January 25, 2012
Lamination and mixing in three fundamental flow sequences driven by electromagnetic body forces
1Department of Aeronautics, Imperial College London, London, United Kingdom.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 26, 2012
Summary
Engineered striations, or lamination, enhance material mixing. Novel "cat
Area of Science:
- Fluid dynamics
- Microfluidics
- Mixing technology
Background:
- Lamination, the degree of striations, is crucial for material mixing.
- Designing efficient sequential mixers requires understanding lamination and stretching.
- Electromagnetic body forces offer a method to control flow geometry for mixing.
Purpose of the Study:
- To engineer lamination for enhanced stretching and design new sequential mixers.
- To experimentally investigate three new mixing sequences driven by electromagnetic forces.
- To analyze the impact of dynamic Lorentz forces on flow geometry and mixing.
Main Methods:
- Generated three mixing sequences: "tendril and whorl," "blinking vortex," and novel "cat's eyes flip."
- Utilized dynamically controlled Lorentz body forces to vary flow geometry via local jets.
- Quantified mixing efficiency using a mixing coefficient based on variance.
Main Results:
- All three sequences showed exponential stretching and lamination of material interfaces.
- Mixing coefficient and rate grew exponentially before reaching a saturation point.
- The "cat's eyes flip" sequence exhibited superior lamination, stretching, and mixing rates compared to the others for the same energy input.
Conclusions:
- Dynamically controlling local jets and integrating lamination can create bakerlike in situ mixers.
- The "cat's eyes flip" sequence demonstrates a highly effective method for sequential mixing.
- This research provides insights for developing novel sequential mixers across various scales.
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