Accession Number:

AD0743053

Title:

The Torque and Turbulent Boundary Layer of Rotating Disks with Smooth and Rough Surfaces, and in Drag-Reducing Polymer Solutions,

Descriptive Note:

Corporate Author:

NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD

Personal Author(s):

Report Date:

1972-04-01

Pagination or Media Count:

54.0

Abstract:

The resisting torque of disks rotating in an unbounded fluid is analyzed on the basis of three-dimensional boundary-layer theory. Smooth and rough surfaces in ordinary fluids and in drag-reducing polymer solutions are considered. A general logarithmic relation is derived for the torque as a function of Reynolds number for arbitrary roughness and arbitrary drag reduction. Special formulas are obtained for smooth surfaces, fully rough surfaces, polymer solutions with a linear logarithmic drag-reduction characterization, and polymer solutions with maximum drag reduction. Relations are also obtained for boundary-layer parameters such as thickness, wall shearing stress, etc. Author

Subject Categories:

  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE