Abstract
An important practical problem in the application and study of drag reduction by polymer additives is the degradation of the polymer, for instance due to intense shearing, especially in recirculatory flow systems. Such degradation leads to a marked loss of the drag-reducing capability of the polymer.
Three different polymer types were tested on degradation effects in a closed pipe flow system. The polymers used were Polyox WSR-301, Separan AP-273 and Superfloc A-110, dissolved in water in concentrations of 20 wppm each. The flow system consisted of a 16.3 mm pipe of 4.25 m length. Two different pumps were used: a centrifugal pump and a disc pump. Different solution-preparation procedures were tried and the experiments were performed at different flow rates.
Superfloc A-110 proved to be both the most effective drag reducer and most resistant to degradation. Because of very fast degradation, Polyox WSR-301 was found to be unsuitable for being used as a drag reducer in re-circulatory systems. The disc pump proved to be much better suited for pumping the polymer solutions than the centrifugal pump. The degradation curve of the combination Superfloc/disc pump showed a plateau-like region with reasonable drag reduction, which makes it possible to perform (laser Doppler) measurements under nearly constant circumstances during a sufficient time.
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References
Baily, F.E. Jr. and Koleske, J.V.,Configuration and Hydrodynamic Properties of the Polyoxyethylene Chain in Solution. Union Carbide Corporation (1987).
Bueche, F., Mechanical degradation of high polymers.J. Appl. Pol. Sc. 4 (1960) 101–106.
Choi, S.U.S., Cho, Y.I. and Kasza, E., Degradation effects of dilute polymer solutions on turbulent friction and heat transfer behaviour.J. Non-Newt. Fluid Mech. 41 (1992) 189–307.
Ellis, A.T., Ting, R.Y. and Nadolink, R.H., Some storage and shear history effects on polymeric friction reduction.J. Hydron. 6 (1972) 66–69.
Gampert, B. and Wagner, P., The influence of molecular weight and molecular weight distribution on drag reduction and mechanical degradation in turbulent flow of highly dilute polymer solutions. In: Gampert, B. (ed.),The Influence of Polymer Additives on Velocity and Temperature Fields, IUTAM Symp. 1984. Springer-Verlag (1985) pp. 71–85.
Harder, K.J. and Tiederman, W.G., Drag reduction and turbulent structure in two-dimensional channel flows.Phil. Trans. R. Soc. Lond. A 336 (1991) 19–34.
Interthal, W. and Wilski, H., Drag reduction experiments with very large pipes.Coll. & Pol. Sc. 263 (1985) 217–229.
Kenis, P.R., Turbulent flow friction reduction effectiveness and hydrodynamic degradation of polysaccharides and synthetic polymers.J. Appl Pol. Sc. 15 (1971) 607–618.
Pollert, J. and Sellin, R.H.J., Mechanical degradation of drag reducing polymer and surfactant additives: a review. In: Sellin, R.H.J. and Moses, R.T. (eds),Drag Reduction in Fluid Flows. Ellis Horwood (1989) pp. 179–188.
Sellin, R.J.H., Hoyt, J.W. and Scrivener, O., The effect of drag-reducing additives on fluid flows and their industrial applications Part 1: Basic aspects.J. Hydr. Res. 20 (1982) 29–68.
Toms, B.A., Some observations on the flow of linear polymer solutions through straight tubes at large Reynolds numbers. In:Proc. 1st Intern. Congr. Rheol. North Holland (1948) pp. II 135–41.
Virk, P.S., Drag reduction fundamentals.AIChE Journal 21 (1975) 625–656.
Virk, P.S., Merrill, E.W., Mickley, H.S., Smith, K.A. and Mollo-Christensen, E.L., The Toms-Phenomenon — Turbulent pipe flow of dilute polymer solutions.J. Fluid Mech. 30 (1967) 305.
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den Toonder, J.M.J., Draad, A.A., Kuiken, G.D.C. et al. Degradation effects of dilute polymer solutions on turbulent drag reduction in pipe flows. Appl. Sci. Res. 55, 63–82 (1995). https://doi.org/10.1007/BF00854224
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DOI: https://doi.org/10.1007/BF00854224