Accession Number : AD0715556

Title :   A Correlation Between Friction Reduction and Molecular Size for the Flow of Dilute Aqueous Polyethylene-Oxide Solutions in Pipes.

Descriptive Note : Doctoral thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CALIF

Personal Author(s) : Kinnier,John Wesley

Report Date : JUN 1970

Pagination or Media Count : 120

Abstract : Pipe-friction factors for dilute aqueous polyethylene-oxide solutions in pipes of nominal diameters of 1/4, 3/8, and 3/4 in. were measured over a two decade range of Reynolds numbers. In the transition region, the amount of drag reduction is dependent upon polymer concentration and wall shear stress as well as Reynolds number. For high Reynolds numbers, where the wall shear stress was high compared to the critical value, no diameter effect was noted. Intrinsic viscosity measurements, made on samples withdrawn from pipe flow, provided direct evidence that polymer degradation take place under flow conditions. Spectrographic measurements indicated that this degradation is mechanical (and not chemical). The relative volume of solution occupied by polymer molecules (represented by the volume of equivalent hydrodynamic spheres) is shown to be a dominant parameter governing the drag-reduction phenomenon for polyethylene-oxide solutions in pipe flow. It is further shown that the equivalent volume ratio may be used to normalize the pipe friction factors for various concentrations of different molecular-weight species of polyethylene-oxide. (Author)

Descriptors :   (*SKIN FRICTION, REDUCTION), (*MOLECULAR PROPERTIES, FLUID FLOW), EPOXY RESINS, PIPES, SOLUTIONS(MIXTURES), CORRELATION TECHNIQUES, REYNOLDS NUMBER, MOLECULAR WEIGHT, THESES

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE