Abstract
Two-color dual laser beam scanning PIV is applied to the measurements of the wake vortices behind an axisymmetric paraboloid to investigate the flows with separation over the body at high angles of attack. In order to record the image with the limited scattering efficiency of small tracer particles, laser beam scanning method was employed with a 3-CCD color digital video camera. The obtained single frame/multi-exposure color PIV image was decomposed into double frame/single exposure images according to the hue component of the pixel values. The developed technique is shown to provide sufficient velocity vectors in the plane normal to the symmetric axis of the body, with the exception in vortex cores. The agreement obtained between the PIV and flow visualization results is seen to be quite reasonable.
