Advanced Undergraduate Laboratory

Department of Physics

University of Toronto

FVF: Fractal Viscous Fingering

Why do fractal patterns so often appear in nature? Radial viscous fingering is a paradigm case of a very general type of fractal growth which includes the dendritic growth of crystals (like snowflakes), diffusion limited aggregation (DLA), dielectric breakdown, electrodeposition, mocha diffusion patterns on pottery, the branching of propagating cracks and bacterial colonies, among many others. In this experiment, both the initial fingering instability and the emergence of the fractal pattern are studied.

This experiment is related to research carried out in Prof. Stephen Morris's Experimental Nonlinear Physics Group.

Write-Up in PDF Format.

(The experiment is new. Contact Prof. Stephen Morris for help.)

A movie showing fractal viscous fingering:

Additional resources:

A thresholded and flood filled image of an air bubble injected into mineral oil in a a very thin gap at a pressure of 30 psi.
This image uses the reflect_pipe method to remove the inlet pipe that you see in the video above.

Last updated on 5 September 2019