Two-Dimensional viscoelastic flow through T-shaped channel were observed by means of flow visualization techniques. In a preceding papery",the authors discussed junction flows. In the present paper additionally two types of branching flows (symmetric and asymmetric flows) and three types of pocket flows (L-shape, reverse L-shape and straight flows) through T-shaped channel were observed. Water solution of polyacrylamide was used as the viscoelastic fluid, and dextrose syrup and water were used

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... s the Newtonian fluids. The results are as follows. In symmetric T-shaped branch flows of viscoelastic fluids two circulating secondary flows formed on the upstream corners of the branch while with Newtonian water similar circulating flows formed on the downstream side of the two corners. A more abrupt change in the direction of flow at the branch was observed with viscoelastic fluids than with Newtonian fluids. In the non-symmetric branch flows of viscoelastic fluids in which one branch made a 90 degrees turn while the other branch flowed straight ahead a secondary flow formed on the upstream corner at a flow rate higher than in symmetric branch flows. Also tested were L, reverse L and "straight" flows. In the L flow the fluid entered the lower branch of the T junction with the upper right branch of the T is closed to form a packet. Reverse L flow was the same as L except the flow direction was reversed. The "straight" flow passed through the upper horizontal part of the T while the lower branch was closed to form a pocket. In the L and reverse L flows of viscoelastic fluids secondary flows formed on the upstream corner of the bend and in the L and "straight" flow a prominent bulge of flow into the pocket was observed. The bulge, however, diminished with increasing flow rate. Numerical simulation of all above flows agreed reasonably with experiments except it failed to predict the bulge of flow into the pocket. 42