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Experiments in Drag-Reducing Polymer Flows

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Advances in Fluid Mechanics Measurements

Part of the book series: Lecture Notes in Engineering ((LNENG,volume 45))

Abstract

Small amounts of high molecular weight polymers (a few parts per million by weight) dissolved in a solvent can reduce the turbulent flow frictional resistance from that of the pure solvent by as much as 90 percent. Since the viscosity of a polymer/solvent mix is slightly increased over that of the solvent alone, the fact that viscous drag is decreased is somewhat surprising. The study of these drag-reducing, non-Newtonian fluid flows received initial impetus from the study of Toms (1948). Since this work, the examination of the turbulent flow properties of dilute solutions of long chain high-molecular weight polymers has generated many hundreds of publications, of which a majority are experimental investigations. This preponderance of experimental studies is no doubt due to the difficult theoretical nature of the problem which must address not only the turbulent kinematics but also the interaction of a viscoelastic fluid with the turbulence. Several excellent reviews of the available experiments and possible explanations of this phenomenon have been published since Toms original work: Lumley (1969) & (1973), Hoyt (1972), Virk (1975), Little et al. (1975), and Berman (1978). Theoretical discussions of the drag reduction phenomenon can be found in Lumley (1973), Berman (1978) and a recent work by Ryskin (1987a). The text that follows includes a review of experimental methods utilized by both rheologists and fluid dynamicists in the examination of turbulent flows of drag-reducing polymer solutions. In addition, we review some of the major experimental findings and make recommendations for future research. Finally, we present some new measurements of wall pressure in a turbulent non-Newtonian channel flow.

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  1. J. V. Lawler

    Present address: Research Division, Hoechst Celanese, Summit, New Jersey, 07901, USA

Authors and Affiliations

  1. Naval Research Laboratory, Washington, D.C., 20375-5000, USA

    E. W. Hendricks, J. V. Lawler, M. P. Horne, R. A. Handler & J. D. Swearingen

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  1. Dept. of Aerospace & Mechanical Engineering, University of Notre Dame, 46556, Notre Dame, IN, USA

    Mohamed Gad-el-Hak

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Hendricks, E.W., Lawler, J.V., Horne, M.P., Handler, R.A., Swearingen, J.D. (1989). Experiments in Drag-Reducing Polymer Flows. In: Gad-el-Hak, M. (eds) Advances in Fluid Mechanics Measurements. Lecture Notes in Engineering, vol 45. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-83787-6_11

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