Paper detail

Realistic prediction and analysis of cavitation bubble dynamics via optical ray-tracing of the corresponding numerical simulations

Experimental analysis of cavitation bubble dynamics typically uses optical imaging. However, images are often severely affected by distortions and shadows due to refraction and total reflection at the liquid--gas interface. Here it is shown that optical ray-tracing can be a powerful tool for the analysis process by assisting in the comparison of experiments to numerical two-phase flow simulations. To this end, realistic ray-tracing images are generated from numerical simulations that correspond to the experimental setup. We apply the method on the jetting dynamics of single bubbles collapsing at a solid wall. Here, ray-tracing can help in the interpretation of raw experimental data, but also in prediction of the complex bubble interface deformations and internal structures during the collapse. The precise shape of the highly dynamical bubbles can be inferred and thereby a correction method for velocity values of the liquid jets can be provided.