Surfactants, turbulent drag reduction

Mechanochemical and chemical reaction engineering aspects in the break down of turbulent drag reduction of cationic surfactant solutions... 

Over the past 60 years, a great deal of applied and theoretical research has been carried out on both polymer and surfactant DRAs because of their potential useful applications and the influence of the additives on both turbulent structure and rheology. Important results include the identification of maximum drag reduction asymptotes (MDRAs) both Virk s MDRA for polymer solutions [Virk et al., 1970 see Eq. (2.5)] and Zakin et al. s MDRA for surfactant solutions [Zakin et al., 1996 see Eq. (2.6)], relating solution nanostructures and rheological properties to macroscopic DR phenomena hypotheses on the influence of DRAs on turbulent structures, mechanisms for turbulent drag reduction, developing heat transfer enhancement techniques, and so on. 

Turbulent drag reduction in homogeneous flows by polymer or surfactant additives is a striking phenomenon with both theoretical and practical implications. On the theoretical side, it remains a challenge to fully understand the drag reduction mechanism and the interaction details between DRAs and the turbulent flow field. New methods, especially computational ones, have been developed to solve this problem, such as direct numerical simulations and stochastic simulations. On the application... 

Kawaguchi, Y, Tawaraya, Y., Yabe, A., Hishida, K., and Maeda, M., Active control of turbulent drag reduction in surfactant solutions by wall heating, Proc. ASME Fluids Eng. Div., 237, 47-52 (1996). 

Recently, turbulent drag reduction by surfactants has been extensively reviewed by Gyr and Bewersdorff (23), Zakin and co-workers (42), and Myska and Zakin... 

FIGURE 13.11 Apparent viscosity versus shear rate of PEO/SDS mixtures. (From Mohsenipour, A.A., turbulent drag reduction by polymers, surfactants and their mixtures in pipeline flow, PhD thesis. University... 

Drag reduction in turbulent flows of dilute high-polymer of surfactant solutions is a striking... 

POLYMER AND SURFACTANT DRAG REDUCTION IN TURBULENT FLOWS... 

Rheology of polymer and surfactant solutions Maximum drag reduction asymptotes Type A and B drag reduction Mean velocity profiles and limiting asymptotes Turbulence intensities and stress balance... 

Bewersdorff, H.-W., Drag reduction in surfactant solutions, in Structure of Turbulence and Drag Reduction, Gyr, A., Ed., Springer-Verlag, Berlin, 1990, p. 293. 

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