Fundamentals of multiple plane stereo particle image velocimetry

For complex flow analysis in air, a stereoscopic particle image velocimetry -based system was developed, tested and applied which allows the determinat ion of all three velocity components in spatially separated planes simultan eously (in order to determine the vorticity vector field for example) or se parated in time (for space-time investigations). For this purpose, the flow field was illuminated with orthogonally linearly polarized light delivered by four frequency doubled Nd:YAG lasers. The light scattered by the tracer particles was separated by means of a polarizing beam-splitter pair onto t he sensors of four progressive-scan CCD cameras in an angular imaging confi guration with Scheimpflug correction.