Jürgen Kompenhans, MEMBER SPIE Deutsche Forschungsanstalt für Luftund Raumfahrt Institut für Strömungsmechanik Center for Quantitative Visualisation BunsenstraXe 10 D-37073 Göttingen, Germany Abstract. In its classical form particle image velocimetry (PIV) extracts two components of the flow velocity vector by measuring the displacement of tracer particles within a double-pulsed laser light she...