STUDY OF MASS-TRANSFER IN VISCOELASTIC LIQUIDS BY SEGMENTED ELECTRODIFFUSION VELOCITY PROBES

Mass transfer on a circular cylinder with a diameter of 0. 52 mm was s tudied in polymer solutions by measuring the directional characteristi cs of a three-segment electrodiffusion velocity probe. The free stream velocity was varied in the range 0.01-0.31 m s-1 and the polyacrylami de concentration in the range 0.001-1% (by mass). A small amount of po lymer produced large changes in mass transfer distribution on the cyli nder in comparison to the distribution in Newtonian liquid. In particu lar it has been shown that the transfer rate in the aft portion of the cylinder is greater than in the front part if the Weissenberg number exceeds some critical value. The situation was identified where the lo cal mass transfer was constant around the cylinder, i.e. the surface w as uniformly accessible to diffusion.