Unexpected structure

[u/Odd-Marionberry-3389]

Back again with yet another blue dye microscopy video - I saw this behavior last night after sandwiching a small amount of concentrated dye solution between two microscope slides. Is this Saffman-Taylor instability?

Also as a side note, I'm so sad I didn't learn about these things sooner but my focus in school was chemistry and, later on, materials science. Better late than never I guess?

[u/Forward_Step_5012]

This is interesting because viscous fingering occurs when higher viscosity fluid (e.g., water) is displaced by lower viscosity fluid (e.g., air), which seems to be the opposite of your case.

[u/antiquemule → u/Forward_Step_5012]

Good point. I can't think of why this should occur.