Magnetic Resonance Imaging of Granular Convection

摘要

We describe experiments that probe the detailed nature of convection patterns occuring in dry, cohensionless granular material subjected to vibrations. For cylindrical containers filled with poppy seeds magnetic resonance imaging (MRI) is used to map the local convection velocity throughout the interior of the system in a noninvasive manner and with high resolution. Using MRI, we also show how granular convection is able to induce size separation in vibrated mixtures of two particle sizes.