Abstract
A novel combination of backlighting and glare point velocimetry and sizing (GPVS) is proposed to measure the size distribution of microbubbles (or microdroplets). This new technique, which we will call laser marked shadowgraphy, avoids sizing out-of-focus bubbles (or droplets) and the associated bias error. Compared to backlighting, this combination also improves the precision of the diameter measurement and allows void fraction measurements. Compared with GPVS, a more robust image processing is obtained. The applicability of the developed technique is demonstrated on a cloud of electrochemically generated hydrogen bubbles.
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Acknowledgments
This research was funded with fellowship SB-031241 and SBO contract number 040092 granted by the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen).
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Dehaeck, S., Van Parys, H., Hubin, A. et al. Laser marked shadowgraphy: a novel optical planar technique for the study of microbubbles and droplets. Exp Fluids 47, 333–341 (2009). https://doi.org/10.1007/s00348-009-0668-8
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DOI: https://doi.org/10.1007/s00348-009-0668-8