The image is of the stereoscopic PIV system from TSI Inc. that we used in our research in the Multiphase Flow laboratory under supervision of Prof. Gad Hetsroni. The research was performed in a flume (water flow in an open-channel) that was made of glass (a part of it you can see in the image).

During the study we compared URAPIV to Insight (the software from TSI) that was version 3.4 at that time. We found excellent agreement between the two results. It is not clear who should be actually happy about the output. TSI has upgraded their software to Insight 3G. This product will include a large portion of Matlab (not open source, unfortunately) and it seems to be the direction. Their competitors, Dantec Dynamics and LaVision, among others, also incorporate Matlab in the analysis of the PIV realizations.

On the right side of the image above one can see the outlet tank and below you can see how it looks when we put 20 parts-per-million (ppm) of surfactant (surface active agent). It is only 80 grams of Agrimul PG 2062 (bio-degradable surfactant from Alkyl Polyglycosides family) but see what it did to our lab