Granular Eruptions: Void Collapse and Jet Formation

René Mikkelsen, Michel Versluis, Elmer Koene, Gert-Wim Bruggert, Deveraj van der Meer, Ko van der Weele, Detlef Lohse

Research output: Non-textual formDigital or Visual ProductsOther research output

28 Downloads (Pure)


Upon impact, sand is blown away in all directions, forming a splash. The ball digs a cylindrical void in the sand and the jet is formed when this void collapses: The focused sand pressure pushes the jet straight up into the air. When the jet comes down again, it breaks up into fragments, i.e., granular clusters. For sufficiently high impact velocity, air is entrained by the collapsing void, forming an air bubble in the sand. This bubble slowly rises to the surface, and upon reaching it causes a granular eruption. This looks like a boiling liquid, or even a volcano! Gallery of Fluid Motion Award-winning entry 2002
Original languageEnglish
Media of outputOnline
Size44 MB
Publication statusPublished - 2002

Cite this