High speed observations of gas bubble collapse due to shock waves
* Präsentierender Autor
Zusammenfassung:Bubble shock waves interaction has been studied both experimentally and numerically. The collapse of cavitation bubbles are responsible for breaking the kidney stones and causing collateral damages in Extracorporeal Shock Waves Lithotripsy. Detailed bubble cloud or multiple bubbles shock waves interaction are difficult to capture experimentally due to the lack of temporal and spatial resolution. Numerically simulating bubble clouds which includes bubble-bubble interaction, reflection of shock waves, and the shielding effect is computational complex and expensive. In this study, we focus on trapping gas bubbles in gelatin and observe their collapse by the lithotripter shock waves using high speed photography up to 1 million frames per second. The gas bubbles are generated through gas diffusion process in the gelatin. They are typically a few hundred microns in diameter. Interesting phenomena are recorded, such as cavitation inception in the gelatin, different oscillation frequencies of the gas bubbles, and the bubbles jetting with jet directions being influenced by the nearby bubbles. We aim to understand how the presence of other bubbles affect the bubble collapse caused by a traveling shock wave.