Accession Number : AD0766787

Title :   Similarity Laws for Turbulent Flow of Dilute Solutions of Drag-Reducing Polymers,

Corporate Author : NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD

Personal Author(s) : Huang,T. T.

Report Date : AUG 1973

Pagination or Media Count : 41

Abstract : Velocity similarity laws, based on a four-layer, mean-velocity-profile model are deduced for turbulent boundary layers with dilute polymer solutions by means of pipe-flow experiments. Measured drag reduction is studied in three domains: undersaturated, optimal, and oversaturated. Drag reduction increases with increasing concentration in the undersaturated domain where the four-layer profile exists in the boundary layer. The boundary between the two domains gives optimal drag reduction; it is determined by the polymer type and concentration and by a Reynolds number based on shear velocity and boundary-layer thickness. The effects of solvent temperature, pipe diameter, polymer type and concentration, and wall shear stress on the measured drag reduction have been investigated. (Modified author abstract)

Descriptors :   (*TURBULENT BOUNDARY LAYER, *HYDRODYNAMICS), (*DRAG, REDUCTION), (*POLYMERS, *FLUID DYNAMICS), VELOCITY, THEORY, MATHEMATICAL MODELS, FLUID FLOW, PIPES, WALLS, SOLUTIONS(MIXTURES), CONCENTRATION(CHEMISTRY), REYNOLDS NUMBER, SHEAR STRESSES, MODEL TESTS, OPTIMIZATION

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE