Saffman-Taylor instability in a Hele-Shaw cell. When viscous fluid is displaced by a less viscous fluid in a thin layer,
a fingering instability forms.
Contributors: Dustin Grace, Jessica Todd, Marilyn Poon and Robert Neilson, University of Colorado, Boulder.
Image created as part of Jean Hertzberg's
Flow Visualization: A Course in the Physics and Art of Fluid Flow.