[O-07] Kitchen Earth Science: its potential for producing diverse goals by hands-on experiments

[O07-P03] A peculiar motion of a falling sphere in a hydrogel suspension: A table-top experiment on magma transport system

★Invited Papers

*Ichiro Kumagai¹, Shinji Shinohara¹, Miyuki Yamada², Kei Kurita³ (1.School of Science and Engineering, Meisei University, 2.Tokyo Keizai University, 3.Tokyo Institute of Technology)

Keywords:magma, suspension, Rheology, Kitchen Earth Science

We have conducted laboratory experiments on a free-fall sphere in a suspension of hydrogel beads to understand the magma transport system. To visualize the flow around the falling sphere, fluorescent tracers were seeded in the interstitial fluid, and the fluid was illuminated by a UV laser light sheet. We also investigated rheological properties of the fluid using ball measuring system, which showed that this suspension has a shear-thinning nature with a yield stress, and the rheological behavior depends on the water content and the size of the gel beads. As the buoyancy of the sphere overcomes the yield stress of the fluid, it starts to fall in the fluid, and the irregular stick-slip motion was observed. The mode of the sphere motion depends on the size of gel grains and the diameter of the sphere. In this presentation, we will demonstrate the peculiar stick-slip motion of the falling sphere in the gel suspension by using the “Kitchen Earth Science” method.