Durability of a Drag Reducing Solution

Abstract

Effectiveness of drag reduction by small addition of a surfactant in the turbulent flow of water depends on the structure and concentration of the additive, temperature of the solution and turbulence intensity, possible flow disturbance by a mechanical obstacle and the content of ions in water, but also on the age of the surfactant solution. We show how important aging effects are in connection with total surfactant concentration, in particular how rheological parameters of the drag reducing solution change with time.

Keywords

• drag reduction
• surfactants
• viscoelasticity
• degradation of additives