Session MA - Turbulent Boundary Layers V.
MIXED session, Tuesday afternoon, November 23
Grand I, Westin Seattle
High resolution DPIV measurements were made over axisymmetric bodies of various diameters. The goal of the research was to test the hypothesis that bodies with non-dimensional radius, a+, less than 28 would not sustain a turbulent boundary layer. Using cables and pipe from 0.24 to 6.0 cm in diameter, an a+ range from 10 to 300 was examined. In all cases, mean and fluctuating velocity statistics clearly indicate the existence of a turbulent boundary layer. For large a+, the turbulence is similar to the canonical flat plate boundary layer. However, for decreasing a+, there are significant departures from the canonical TBL. Variations in turbulence quantities as a function of a+ will be presented along with insights into how decreasing radius alters turbulent structure.