(62b) Detection of Fluidization with Real-Time Magnetic Resonance Imaging
World Congress on Particle Technology
Tuesday, April 24, 2018 - 2:00pm to 2:20pm
Here we present a MRI methodology that can discriminate between fluidized and unfluidized areas in 3D beds of considerable size (cylindrical bed; diameter 190 mm and height 300 mm) at a frame rate of 20 Hz. The high temporal resolution of this technique allows studying not only the presence of dead zones but also their formation and disintegration. The presented measurement technique bases on a recent development in real-time probing of granular dynamics with MRI which uses array detection of the magnetic resonance and engineered granular signal sources7. It exploits both spin saturation effects and diffusion attenuation to create a strong dependency of the signal on particle motion.
We anticipate the presented technique to be a starting point for more sophisticated studies on the formation of dead zones in fluidized beds, such as determining the influence of internals, the distributor or bed geometry. Moreover, we envisage that the technique is suited to provide fundamental physical insights on the nature of fluidization, its relations to jamming and the glass transition8.
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