Drag of Spheres in Dilute Aqueous Solutions of Poly-(Ethylene Oxide) Within the Region of the Critical Reynolds Number

摘要

The drag reducing effect of poly(ethylene oxide) additives on blunt bodies in water was investigated by examining the behavior of a sphere in both subcritical and supercritical Reynolds number regions. Drop tests were conducted in water and in concentrations of poly(ethylene oxide) WSR 301 ranging in concentration from 50 wppm to 1000 wppm. Reduction in drag was noted for all concentrations in the Reynolds number range of 40,000 to 350,000. A critical Reynolds number of 450,000 was observed for dilute solutions (50 and 100 wppm), while more concentrated solutions exhibited a uniformly decreasing drag. These results are explained by examining the interaction of profile and friction drag, together with the effects of polymer additives upon wake diameter size. (Author)