Turbulent Flow Over a Disk Normal to a Wall

Abstract

Measurements have been taken of local mean velocities and turbulence intensities in an external separated flow situation in air using a forward, dual-scatter, laser Doppler anemometer. Frequency shifting of the incident beams was used so that the flow direction could be determined and high turbulence intensities could be measured. A simple fluidized bed particle generator was used to generate titanium oxide particles for introduction into the main stream of the airflow as scattering particles for the laser light. An axisymmetrical external separated flow was achieved by placing a disk normal to the airstream in a large duct. The results thus obtained, together with the turbulent kinetic energy deduced, presented a good description of the flow situation.