Recounting Twenty Years of Digital PIV, its Origins and Current Trends

Kurzfassung

Early 1989 the first image sequences of single exposed particle images were acquired for a low speed water flow and for the first time demonstrated the double-frame, single-exposure PIV recording and processing concept, that has become the most common implementation of PIV up until today. The article provides a historical perspective of the development of digital PIV in the presence of the then already well established photographic PIV methods. Initially the implementation of the two techniques seemed to be almost contradictory, but a steady improvement of the theoretical background during the 1990's clarified that the two techniques are merely different implementations of the same measurement principle. While digital PIV made handling of time-resolved image sequences viable, image data of this type was already available by the late 1920's to researchers such as Prandtl. Modern PIV processing nowadays allow processing of this antique data which by itself shows the importance of carefully documenting and archiving valuable data.