DRAG-REDUCING FLUIDS IN A FREE TURBULENT JET.

Abstract

To determine whether drag reduction is the result of turbulence dampening per se, the decay characteristic of a free turbulent jet was investigated. The work was suggested by recent boundary-layer studies showing that fluid drag reduction is caused by the presence of high-molecular-weight polymers in solution. The jet, having all the properties associated with turbulence except those caused by the presence of a wall, provided an ideal tool for the experiment. It was found that in a water solution of drag-reducing polymer, shear stress was reduced in the nozzle but not in the free jet. Drag reduction was therefore concluded to be a phenomenon of the wall because the character of the turbulence that is beyond the influence of the wall resembles the character of the turbulence in a free jet, which was found to be unaffected by the drag-reducing agent. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1966
Accession Number
AD0631209

Entities

People

  • Donald N. Jackley

Organizations

  • Naval Air Weapons Station China Lake

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Boundary Layer
  • Drag
  • Drag Reduction
  • Layers
  • Molecular Weight
  • Personality
  • Reducing Agents
  • Shear Stresses
  • Stresses
  • Turbulence

Fields of Study

  • Physics

Readers

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