FRICTIONAL DRAG REDUCTION,

Abstract

The paper deals with changes in the turbulent boundary layer resulting in frictional drag reduction. Experiments are described, showing a remarkable decrease in friction coefficients for dilute solutions of separan AP 30 and guar gum. It is shown from these data, and those available in literature for all kinds of additives, that drag reduction effects nearly always coincide with a decrease in the universal constant k. This contradicts the generally accepted Reynolds similarity principle, which is the conventional assumption on which the analysis of the turbulent boundary layer is usually based. Furthermore, it appears that an additional entity must exist which influences the mechanism of turbulent flow. (Author)

Document Details

Document Type
Technical Report
Publication Date
Dec 15, 1964
Accession Number
AD0615673

Entities

People

  • C. Elata
  • J. Tirosh

Organizations

  • Technion – Israel Institute of Technology

Tags

DTIC Thesaurus Topics

  • Additives (Chemicals)
  • Boundaries
  • Boundary Layer
  • Coefficients
  • Drag
  • Drag Reduction
  • Friction
  • Layers
  • Turbulent Boundary Layer
  • Turbulent Flow

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Polymer Science and Technology
  • Theoretical Analysis.