Figure 1. Vortex fluidic device (VFD).

(a) Cross section showing the components of the device. (b) Average film thickness (mm) versus tilt angle θ, which was determined mathematically from the surface coverage of the film for 1 mL of water containing a low concentration of dye, in a standard 10 mm NMR tube with distances along its length marked externally to establish the upper level of the liquid. (c) Photographs showing the film of liquid developed for different speeds, for 3 mL of an aqueous solution, for θ = 45°, with 3000 rpm showing a quasi-parabolic film.