Publications in Scientific Journals:

M. Koch, J. M. Rossello, Ch. Lechner, W. Lauterborn, J. Eisener, R. Mettin:
"Theory-assisted optical ray tracing to extract cavitation-bubble shapes from experiment";
Experiments in Fluids, 62 (2021), 3.

English abstract:
Experimental analysis of cavitation bubble dynamics typically uses optical imaging and photographic recording. However,
the images are often severely affected by distortions and shadows due to refraction and total reflection of the illuminating light
at the liquid-gas interface of the bubble. Optical ray tracing may become a powerful tool for the analysis process by assisting
in the comparison of experiments to numerical two-phase flow simulations. The novelty of the present approach consists
in digitizing almost the complete experimental arrangement with all its optically relevant elements and objects-including
a numerical model of the yet unknown bubble-and numerically photographing the scene via ray tracing. The method is
applied to the jetting dynamics of single bubbles collapsing at a solid wall. Here, ray tracing can help in the interpretation
of raw experimental data concerning the complex bubble interface deformations and internal structures during the collapse.
The precise shape of the highly dynamical bubbles can be inferred, thus ray tracing provides a correction method for velocity values of the liquid jets. Strong evidence is found for the existence of an ultra-short-time, fast jet, exceeding velocities
known to date in the field.

"Official" electronic version of the publication (accessed through its Digital Object Identifier - DOI)

Created from the Publication Database of the Vienna University of Technology.