Drag reduction by cation surfactants: The relation to physicochemical and micellar characteristics

Povkh, I. L.; Serdyuk, A. I.; Наумов, А. В.; Kovalenko, N. P.

doi:10.1007/bf00824967

Cited by 2 publications

(2 citation statements)

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“…Among the surfactants used for drag reduction one has to differentiate between nonionic, anionic, and cationic surfactants. Mixtures of 1-naphthol with other cationic surfactants based on quaternary ammonium salts have been described [11,17,18]. This disadvantage is avoided by a combination of the cationic surfactant hexadecyltrimethylammonium bromide, often called CTAB, and 1-naphthol [8,11,12,15,16].…”

Section: Introductionmentioning

confidence: 99%

The behaviour of drag-reducing cationic surfactant solutions

Bewersdorff

Ohlendorf²

1988

Colloid & Polymer Sci

121

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The behaviour of two types of drag reducing surfactant solutions was studied in turbulent flows in pipes of different diameters. Our surfactant systems contained rod-like micelles; they consisted of equimolar mixtures of n-tetradecyltrimethylammonium bromide, n-hexadecyltrimethylammonium bromide, and sodium salicylate. The structure of the turbulence was studied using a laser-Doppler anemometer in a 50 mm pipe. In the turbulent flow regime both surfactant solutions exhibited characteristic flow regimes. These flow regimes can be influenced by changing the amount of excess salt, the surfac tant concentration, or the temperature. Shear viscosity measurements in laminar pipe and Couette flows show the occurrence of the so-called shear-induced state, where the viscosity increases and the surfactant solution becomes viscoelastic. The shape of the turbulent velocity profile depends on the flow regime. In the turbulent flow regime at low Reynolds numbers, velocity profiles similar to those observed for dilute polymer solutions are found, whereas at maximum drag reduction conditions more "S-shaped" profiles that show deviations from a logarithmic profile occur. An attempt is made to explain the drag reduction by rod-like micelles by combining the results of the theological and the turbulence structure measurements.

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Section: Introductionmentioning

confidence: 99%

The behaviour of drag-reducing cationic surfactant solutions

Bewersdorff

Ohlendorf²

1988

Colloid & Polymer Sci

121

View full text Add to dashboard Cite

show abstract

“…They also found that cationic surfactants with long-chain alkyl groups, such as C 22 , were effective in DR at high temperatures, while short-chain surfactants were effective at low temperatures, and that sometimes the addition of a shortchain surfactant to a long-chain one was beneficial to the overall process. The temperature effect on DR was also investigated by Povkh et al (1980). …”

Section: Introductionmentioning

confidence: 99%