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Updated: May 29, 2026
07:33
Quantifying Mixing using Magnetic Resonance Imaging
Published on: January 25, 2012
Segregation in horizontal rotating cylinders using magnetic resonance imaging.
Thoa T M Nguyen1, Andrew J Sederman, Michael D Mantle
1Department of Chemical Engineering, University of Cambridge, Cambridge CB2 3RA, United Kingdom. thoa.nguyen@cantab.net
Summary
Granular materials segregate radially and axially in rotating cylinders. Magnetic Resonance Imaging (MRI) reveals particle migration and band merging dynamics, offering insights into granular flow.
Area of Science:
- Physics
- Engineering
- Materials Science
Background:
- Granular materials exhibit complex flow behaviors.
- Segregation phenomena, like radial and axial segregation, are crucial in industrial processes.
- Understanding these dynamics is key to controlling granular flows.
Purpose of the Study:
- To investigate the dynamics of radial and axial segregation in granular materials.
- To visualize and quantify particle segregation in a horizontal rotating cylinder.
- To provide experimental evidence for granular flow mechanisms.
Main Methods:
- Utilized Magnetic Resonance Imaging (MRI) for noninvasive observation.
- Acquired high-resolution 3D static and 2D real-time images.
- Measured quantitative local particle concentrations based on magnetic resonance responses.
Main Results:
- Observed and documented radial segregation, band formation, and band merging.
- Quantified the rate of local particle concentration increase during segregation.
- Provided evidence of particle migration in the bulk material, challenging solid-body assumptions.
Conclusions:
- MRI is effective for studying granular material dynamics with high resolution.
- Experimental data support numerical simulations of band merging.
- Granular flow beneath the avalanche layer is not a solid body, indicating complex internal motion.
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