Accession Number : AD0689385

Title :   AN INVESTIGATION OF VELOCITY PROFILES IN THE LAMINAR SUBLAYER WITH NON-NEWTONIAN ADDITIVES USING HIGH SPEED PHOTOMICROSCOPY.

Descriptive Note : Final technical rept. Sep 65-May 69,

Corporate Author : MASSACHUSETTS UNIV AMHERST ENGINEERING RESEARCH INST

Personal Author(s) : Carver,Charles E. , Jr. ; Nadolink,Richard H.

Report Date : MAY 1969

Pagination or Media Count : 78

Abstract : The report describes the development of a high speed photomicroscopic technique, using dark-field microscopy, for the measurement of turbulent velocity distributions in a circular pipe. The method is especially adapted to velocity measurements extremely close to a boundary, of the order of five microns. Velocities are obtained from the analysis of 16 mm film exposure with a high speed camera, due to the motion of illuminated polystyrene tracers, 1.305 microns in diameter, dispersed in distilled water and aqueous solutions of non-Newtonian additives. An electronic flash time base is used to synchronize absolute and relative motion for a permanent record on the film. The photomicroscopic method was used to determine velocity distributions of distilled water and aqueous solutions of the non-Newtonian additives Polyox-301, CMC, and Polyhall-27, flowing in a circular lucite channel 5030 microns in diameter, at a Reynolds number of 4,000. Additive concentrations of 1/100% and 1/10% by weight were used. The results for distilled water indicate excellent agreement with the postulated linear velocity distribution for flow in the laminar sublayer. Polyox-301 at both concentrations displayed a marked increase in the laminar sublayer thickness, as determined by the slope of the laminar sublayer velocity profile, while CMC and Polyhall-27 showed little deviation with distilled water. A quantitative description of the laminar sublayer structure with and without additives is also incorporated. (Author)

Descriptors :   (*TURBULENCE, *PHOTOMICROGRAPHY), VELOCITY, ADDITIVES, POLYMERS, DRAG, REDUCTION, PIPES, DISTRIBUTION, BOUNDARY LAYER, SOLUTIONS(MIXTURES), REYNOLDS NUMBER, THESES

Subject Categories : Photography
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE