Measurements with a redesigned 3D-PTV system in natural and mixed convection

The paper reports on the application of scientific CMOS cameras and high power LED light sources for three-dimensional particle tracking in large enclosures. An open source software is adapted to work with 16 bit grey value images. As fixed thresholds pointed out to be inappropiate for particle detection in 16 bit images due to temporal and spatial brightness variations in large fileds of view a method has been implemented to select a threshold based on the histogram of an image or image area. The redesigned system has so far been used for investigations in two experimental facilities. The settings and methods as well as an extract of the results are presented in the following.

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