Radial and axial dispersion in Taylor-Couette and Poiseuille vortex flows

(M)ass transport in Taylor-Couette and Poiseuille vortex flows has been exp erimentally investigated by dye injection, particle tracking and electroche mical techniques. An annular cavity has been built with an inner/outer radi us ratio of 0.5, with a fixed outer cylinder and a rotating inner one. With out any axial flow, the standard Taylor-Couette flow was observed and the S herwood number for radial dispersion measured. When a low axial flow rate w as imposed (Re-a < 10), a mechanism for axial dispersion similar to the dis persion of a wave packet was drawn from visualization results. (C) 2001 Els evier Science Ltd. All rights reserved.