SIMILARITY LAWS FOR TRUBULENT FLOW OF DILUTE SOLUTIONS OF DRAG-REDUCING POLYMERS

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 found to have three domains: undersaturated, optimal, and oversaturated. The drag reduction does not increase with increasing concentration in the oversaturated domain where a strong interactive layer dominates the entire linear logarithmic region of the boundary layer. 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. Pipe- flow experiments have been made to study the drag-reduction characteristics in the undersaturated domain. The effects of solvent temperature, pipe diameter, polymer type and concentration, and wall shear stress on the measured drag reduction have been investigated.

• Corporate Authors:

  Naval Ship Research and Development Center

  Ship Performance Department
  Bethesda, MD  United States  20034
• Authors:
  • Huang, T T
• Publication Date: 1973-8

Media Info

• Features: References;
• Pagination: 40 p.

Subject/Index Terms

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

Filing Info

• Accession Number: 00050495
• Record Type: Publication
• Source Agency: Naval Ship Research and Development Center
• Report/Paper Numbers: Report 4096
• Files: TRIS
• Created Date: Jan 4 1974 12:00AM