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Clear existence of three drag reduction zones was observed: stable transitional zone, unstable transitional zone and in particular the third turbulent drag reduction zone.The dominant factor which influenced DR in the transitional zone was the addition of CTAB + NaSal. In the third zone, the addition of PEO had decisive influence on the DR intensity. The increase of PEO concentration enhanced DR in this zone.The influence of pipes diameter on the DR was investigated. The increase of pipe diameter caused clear extension of the stable transitional zone. In the third zone DR increased while decreasing pipe diameter.Analyses showed that the value of the n flow index was not an important factor in the DR.The results indicate that polymer-micellar solutions combine and intensify positive features of their pure polymer and micellar equivalents, providing efficient DR in a wider range of the Reynolds numbers.

-The main aim of this paper is to present a possibility to enhance the drag reduction effect in straight pipe flow by the simultaneous addition to the transported liquid of a small amount of high molecular weight polymers and surfactants. Qualitative analysis of the polymer-micellar additive influence on the shape and character of flow resistance curves has been performed. Also multicomponent polymer-micellar solution flow resistance curves were compared with appropriate single additive polymer or surfactant solution flow resistance curves. The experimental data shows that, for polymer-micellar solutions, the stable transitional zone between the laminar and the turbulent flow regions is extended toward higher values of the critical Reynolds numbers. Occurrence of the phenomenon can be explained by the flow laminarization caused by polymer-micellar aggregates. Existence of the third extended drag reduction zone in the turbulent range of flow has also been observed for the first time.