Measurement of Unsteady Flow Phenomena by Flow Tagging
Pictures of Vortex Breakdown in a Closed Cylindrical Container
by Scott Harris
Basically, what I have is a quartz cylinder with a rotating lid. Figure 1 gives you an idea of what it looks like. The Reynolds number is Re=Omega R2/nu. The only other non dimensional ratio needed to completely describe this flow is delta=H/R.
Figure 2 shows a graph of the different behaviors this flow can undergo (I scanned this plot from the paper by Escudier ) By measuring the displacement of the lines that I tag into a flow, I can compute velocity data.
Some of the things I'm working on related to the flow tagging technique include ray tracing methods to remove distortion in images caused by viewing flows through curved windows, multiple camera techniques to extract three dimensional data, and techniques to identify lines and use their motion to compute velocities. In the regions of the parameter space (Re, delta) where the flow can be computed accurately, I intend to preform very accurately controlled experiments and compare the PHANTOMM data to computations in order to validate the technique. Then I want to examine new regions of (Re, delta) that have not been previously studied. In particular the transition to turbulence and the departure from axisymmetry.
 M.P. Escudier. Observations of the flow produced in a cylindrical container by a rotating endwall.
Experiments in Fluids, 2:189-196, 1984.