Accession Number : ADA017875

Title :   Large Structure Dynamics and Entrainment in the Mixing Layer at High Reynolds Number.

Descriptive Note : Technical rept.,

Corporate Author : PURDUE UNIV LAFAYETTE IND PROJECT SQUID HEADQUARTERS

Personal Author(s) : Dimotakis,Paul E. ; Brown,Garry L.

Report Date : AUG 1975

Pagination or Media Count : 61

Abstract : Observations were made on a turbulent mixing layer in a water channel at Reynolds numbers up to 3 million. Flow visualization with dyes again revealed large coherent structures and showed their role in the entrainment process; observations of the reaction of a base and an acid indicator injected on the two sides of the layer, respectively, gave some indication of where molecular mixing occurs. Autocorrelations of streamwise velocity fluctuations, using an LDV, revealed a fundamental periodicity associated with the large structures. Some possible consequences of initial conditions and the influence of apparatus geometry are discussed.

Descriptors :   *Turbulent flow, *Mixing, *Fluid dynamics, Turbulent diffusion, Layers, Reynolds number, Entrainment, Flow visualization, Statistical processes, Scale, Water flow, Channel flow, Water tunnels, Laser velocimeters, Shear properties

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE