Journal of Non-Newtonian Fluid Mechanics, 41 (1992) 323-337 Elsevier Science Publishers B.V., Amsterdam 323 A study of submerged pseudoplastic laminar jets C. Jordan *, G.W. Rankin and K. Sridhar Department of Mechanical Engineering and Fluid Dynamics Research Institute, University of Windsor, Windsor, Ontario N9B 3P4 (Canada) (Received August 21, 1989; in revised form July 29, 1991) Abstract An experimental and theoretical study of an axisymmetric, laminar submerged jet of a pseudoplastic fluid was carried out. The laminar jet was formed by forcing a polymer solution through a long tube into a large chamber. The experimental velocity profiles were taken with the aid of a Laser Doppler Anemometer which was especially suited for this study because of its non-intrusive nature. No difficulties associated with the birefringence of the aqueous polymer solutions were encountered. In fact, a higher data rate was obtained than with the solvent alone. The fluid (Separan AP30) seemed to be quite well suited for the study due to its desirable non-New- tonian properties and its optical clarity. The nondimensional centreline velocity decay and jet spread did not change significantly as the concentration of the polymer solution was increased. A non-dimensional axial distance which makes use of the diameter of the tube and also includes a Reynolds number based on the viscosity of the fluid at the tube wall was found to successfully collapse the experimental data. An implicit finite difference scheme was used to solve the continuity and momentum equations. Two different rheological models, namely, the power-law and the power-series viscosity models, were employed. The power-series model prediction was in better agreement with the experi- mentally determined velocity data than the power-law model prediction. The velocity distribution and axial variation of the centreline velocity were accurately predicted. The prediction of jet spread was not as good. * Currently with GM1 Engineering and Management Institute, Flint, Michigan, USA. 0377-0257/92/$05.00 0 1992 - Elsevier Science Publishers B.V. All rights reserved