Drag Reduction of Turbulent Flows by Additives

This text shows how fibres, polymer molecules or surfactants at very dilute concentrations can reduce the drag of turbulent flow, leading to energy savings. The dilute solutions are considered in terms of the physical chemistry and rheology, and the properties of turbulent flows are presented in sufficient detail to explain the various interaction mechanisms. The text may be useful reading for those active in fundamental research on turbulence and those seeking to apply the effects described.