EFFECT OF MOLECULAR WEIGHT AND SEGMENTAL CONSTITUTION ON THE DRAG REDUCTION OF WATER SOLUBLE POLYMERS.

Abstract

Tube flow data on some 16 polymers indicate that drag reduction is a function of molecular contour length, segmental side groups, concentration, pipe diameter and Reynolds number. The maximum drag reduction actually obtained with any drag reducing polymer is approximately 80% of that which would be obtained if completely laminar flow was maintained. A relationship that correlates drag reduction, concentration and molecular dimensions is suggested for a constant Reynolds number and pipe size. It infers that a critical concentration of polymer exists, below which no drag reduction occurs. Also for some given concentrations and pipe size a critical velocity exists below which no drag reduction occurs. Rheological data for two polymer solutions are presented in terms of elastic energy. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1965
Accession Number
AD0625801

Entities

People

  • Gail T. Pruitt
  • Horace R. Crawford

Tags

DTIC Thesaurus Topics

  • Diameters
  • Drag
  • Drag Reduction
  • Flow
  • Laminar Flow
  • Molecular Weight
  • Reynolds Number

Readers

  • Fluid Dynamics.
  • Polymer Science and Technology

Technology Areas

  • AI & ML