FLOW VISUALIZATION OF THE NEAR-WALL REGION IN A DRAG-REDUCING CHANNEL FLOW

Study to determine whether the addition of drag-reducing macromolecules alters the structure of the viscous sublayer and thereby modifies the production of kinetic energy in turbulent wall flows. This was accomplished by visualizing the near-wall region of a fully developed two-dimensional channel flow. Motion pictures were taken of dye injected into the near-wall region. Both water and a dilute drag-reducing polyethylene oxide--FRA solution were used as working fluids. The data show that the time between bursts for an individual streak in a drag-reducing flow has the value for a water flow at the reduced wall shear. Evidence strongly suggests that the dilute polymer solution decreases the production of turbulent kinetic energy by inhibiting the formation of low-speed streaks.

• Corporate Authors:

  Cambridge University Press

  200 Euston Road
  London NW1,   England 
• Authors:
  • Donohue, G L
  • Tiederman, W G
  • Reischman, M M
• Publication Date: 1972-12-12

Media Info

• Features: References;
• Pagination: p. 559-575
• Serial:
  • Journal of Fluid Mechanics
  • Volume: 56
  • Issue Number: Pt 3
  • Publisher: Cambridge University Press

Subject/Index Terms

• TRT Terms: Additives; Boundary layer; Drag; Flow visualization; Polymers; Turbulence; Turbulent boundary layer; Two dimensional flow
• Old TRIS Terms: Drag reduction; Polymer additives
• Subject Areas: Design; Marine Transportation;

Filing Info

• Accession Number: 00046658
• Record Type: Publication
• Source Agency: Engineering Index
• Files: TRIS
• Created Date: Oct 31 1973 12:00AM