Effect of polymer concentration and roughness of pipes on friction in fluid flows

The phenomenon of drag reduction by addition of polymer to a solvent has been one of the most fascinating subjects of Fluid Mechanics in recent years. Despite many years of intensive research the mechanism is not fully understood. This thesis provides an experimental study of this phenomenon of drag reduction (reduction of friction factor) with effect to the concentration of the fluid, the roughness of straight pipes and the different types of curved pipes. The experimental results reveal that significant reduction can be achieved with higher concentrations of polymer

additives, but the drag reduction is reduced with the increase in pipe roughness and the radius of curvature in curved pipes show considerable effect on the drag reduction.