Flow visualization using fluorescence from locally seeded I-2 excited by an ArF excimer laser

A new concept for flow visualization is demonstrated in which fluorescence from locally seeded iodine is viewed in the wake of simple aerodynamic mode ls at Mach 6. Localized seeding is performed by painting a small area of a ceramic model with a tincture of iodine. When the model is injected into th e flow, the adsorbed iodine is entrained into the boundary layer, follows t he model contour, and ultimately mixes into the wake region. Planar "snapsh ots" of the wake flow are taken by exciting the iodine with an ArF excimer laser sheet at 193 nm and observing the fluorescence in the 210-600 nm regi on with an intensified CCD camera.