Drag reduction polymers

McCormick CL, Hester RD, Morgan SE, Safieddine AM (1987) Model water-soluble acrylamide copolymers for the study of polymeric drag reduction Polym Mater Sci Eng 57 840... 

Patterson GK, Zakin JL, Rodriguez JM (1969) Drag reduction. Polymer solutions, soap solutions and solid particle suspensions in pipe flow Ind Eng Chem 61 22... 

Patterson, G.K. Zakin, J.L. Rodriguez, J.M. Drag reduction polymer solutions, soap solutions, and solid particle suspensions in pipe flow. Ind. Eng. Chem. 1969, 61 (1), 22-30. 

Choi, H. J., Kim, C. A., Sohn, J.-L, and Jhon, M. S., An exponential decay function for polymer degradation in turbulent drag reduction, Polym. Degrad. Stabil., 69, 341-346... 

Aqueous solutions of neutral polymers as well as polyelectrolytes are of great use in different technical areas, as for instance in drag reduction, polymer flooding, flocculation sludge dewatering etc. Table 1 illustrates the production-levels of different technical applications for different water soluble polymers. 

The addition of small amounts of certain matc rials to fluids undergoing turbulent flow causes a reduction in pressure loss called drag reduction. Polymer solutions, solid suspensions in liquids and in gases, soap and surfactant solutions have all demonstrated this phenomenon. 

Hoyt, J. W., Turbulent-flow interaction and drag reduction, Polymer-Flow Interaction (Y. Rabin ed.), American Institute of Physics, New York, 1985, p. 95. 

Aggregation in dilute solutions of high molar mass poly(ethylene) oxide and its effect on polymer turbulent drag reduction. Polymer, 50, 261-270. 

Kulicke, W.-M., Kotter, M. and Grager, H. Drag Reduction Phenomenon with Special Emphasis on Homogeneous Polymer Solutions. Vol. 89, pp. 1—68. 

The presence of small amounts of dissolved polymer can alter sizably the aerosol particle dimensions when the solutions are sprayed. This antimisting property has received special attention in an effort to develop additives for jet fuel to prevent accidental ignition following crash landing. As in drag reduction, the polymer... 

The effect of polymer additives on turbulent flow is at the origin of the important phenomenon of drag reduction and has found other industrial applications such as oil recovery and antimisting action. Drag reduction in dilute polymer solutions... 

Chain degradation in turbulent flow has been frequently reported in conjunction with drag reduction and in simple shear flow at high Reynolds numbers [187], Using poly(decyl methacrylate) under conditions of turbulent flow in a capillary tube, Muller and Klein observed that the hydrodynamic volume, [r ] M, is the determining factor for the degradation rate in various solvents and at various polymer concentrations [188], The initial MWD of the polymers used in their experiments are, however, too broad (Mw/Iiln = 5 ) to allow for a precise... 

A review on drag-reducing polymers is given in the literature [1359]. It has been suggested that drag reduction occurs by the interactions between elastic macromolecules and turbulent-flow macrostructures. In turbulent pipe flow, the region near the wall, composed of a viscous sublayer and a buffer layer, plays a major role in drag reduction. 

In the extensive literature on polymer drag reduction, it has occasionally been reported that a continuous thread of a high-concentration polymer solution injected into the axis of a pipe produces a drag-reduction effect on the water flow in the pipe [856]. The thread seems to persist through the length of the pipe and little, if any, diffusion of polymer to the walls of the pipe is apparent. 

A polymer of the polyacrylamide type was injected as a 0.5% solution from an axially-placed nozzle at the bellmouth entrance. The experiments showed that the central thread provided drag reduction almost equivalent to premixed solutions of the same total polymer concentration flowing in the pipe. Overall concentrations of 1, 2, 4, and 20 ppm were used. Moreover, the effects were additive 2 ppm thread overall concentration plus 2 ppm premixed gave drag reductions equivalent to 4 ppm of either type. Reynolds numbers of up to 300,000 were investigated. In other experiments, a number of different polymer fluids were injected on the centerline of a water pipe-flow facility [857]. Two distinct flow regions were identified ... 

Reynolds numbers above 25,000, at which centerline injection acted as a rather efficient mixing device for water-soluble polymer and no drag-reduction, resulted from materials insoluble in water... 

It has been shown that hydrogen bonding-mediated interpolymer complexes can be powerful drag reducers. The drag-reduction levels in such polymer systems increase dramatically by a factor of 2 to 6 when compared with their nonassociating polymeric precursors. Their shear stability is also shown to be significantly enhanced [1156]. 

J. W. Hoyt and R. H. J. Sellin. Polymer threads and drag reduction. Rheol Acta, 30(4) 307-315, July-August 1991. 

S. Malik, S. N. Shintre, and R. A. Mashelkar. Process for the preparation of a new polymer useful for drag reduction in hydrocarbon fluids in exceptionally dilute polymer solutions. Patent US 5080121, 1992. 

Kim, O.K., Little, R.C., and Ting, R.Y. "The Correlation of Drag-Reduction Effects with Polymer Intrinsic Viscosity," J. Colloid Interface Sci.. 1974, 47(2). 

Although the exact mechanism is debatable, Darby and Chang (1984) and Darby and Pivsa-Art (1991) have presented a model for turbulent drag reduction based on the fact that solutions of very high polymers are visco-... 

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