When I first came across this link:
http://www.efluids.com/efluids/galle...ance_page.jsp*
I thought: "It looks just like maculae." And that led me to look at
Cymatics:
http://en.wikipedia.org/wiki/Cymatics -standing waves formed from
acoustics.

I got lost (quite easily) on the physics but the salient point in this
is that the laminar(?) waves on the left of the drum have the effect
of inducing resonant waves on the right. Which lead me down the garden
path of time lags in geophysics. Time lags such as the secondary
tides.

And the wave trains of aftershocks in seismology. Everything in fact
from the so called doppler effect to the way that golf balls and
bullets are designed.

* Smoke-Wire Technique:

The technique for applying this visualization method consists of a
fine wire mounted in the flow, coated with oil, and then heated by
running an electrical current through the wire. When a small amount of
oil is spread across the wire, the oil flows all around and beads up
on the wire due to the oil's surface tension.

As the electricity passes through the wire, a smoke filament is
generated by each of these small oil beads. According to Cornell, the
particles which make up these filaments are more correctly a vapour-
condensation aerosol, or actually small liquid particles (= 1 µm
diameter), and are not true smoke particles.

However, the filaments will be referred to as smoke in this paper:

http://pdf.aiaa.org/preview/1981/PV1981_412.pdf

(Just threw that last bit in to explain the actual diagramme and how
it was drawn.)