Dividing Flow Properties of Newtonian Fluid and Visocoelastic Fluid. 1st Report, Flow Patterns and Energy Losses in Two Dimensional Steady Laminar Flow of Newtonian Fluid.

Abstract

Flow patterns were visualized, and energy losses due to flow branching were measured in laminar dividing flow of glycerine and its solutions in channel junctions with branching angles of 45° (Y-branch) and 90° (T-branch). Two separation zones were observed. The sizes of the separation zones depend on the Reynolds number (Re1), the branching angle, the ratio of the cross-sectional area of the lateral conduit to that of the main conduit (m) and the dividing flow rate. The energy loss coefficients decrease with increasing Re1, but their rate of decrease decreases with increasing Re1 as the sizes of the separation zone increase. The relationship between the energy loss coefficient and the dividing flow rate depends considerably on the size of the separation zone. The loss coefficients for the lateral conduit of the T-branch are larger than those of Y-branch, and those with m=0.5 are larger than those with m=1. The loss coefficients for the main conduit do not depend very strongly on the branching angle or m.