Tootfinder

Granular focused jet
Kazuya U. Kobayashi, Pradipto, Yoshiyuki Tagawa
https://arxiv.org/abs/2508.11905 https://arxiv.org/pdf/2508.11905

Granular focused jet
We investigated the formation of granular focused jets defined as narrow upward ejections of grains triggered by impulsive forces and shaped by kinematic focusing on a concave free surface. The jets were generated from nonfluidized granular beds, in contrast to existing granular Worthington jets that originate from fluidized layers. To elucidate the jet dynamics, we performed experiments in which a test tube partially filled with dry glass beads was dropped onto a flat rigid floor, systematical…