Abstract
A two-color dual laser beam scanning PIV is applied to the wind tunnel experiments on a paraboloidal nose and cylindrical afterbody to measure flow fields around a body at high angles of attack. In order to record the image with the limited scattering efficiency of small tracer particles, two-color laser beam scanning method was employed with a 3-CCD color digital video camera. An obtained single frame/double exposure color PIV image was decomposed into double frame/single exposure image sequences according to the hue component of the pixel values. A double correlation PIV method was developed for the color double exposure PIV recordings to eliminate correlation anomalies. 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 was seen to be quite reasonable.
