Ex uno plures: how to construct high-speed movies of collapsing cavitation bubbles from a single image

Abstract

The time-resolved visualization of the dynamics of a cavitation bubble usually requires the use of expensive high-speed cameras, which often provide a limited spatial resolution. In the present study, we propose an alternative to these high-speed imaging techniques. The method is based on the recently introduced virtual frame technique, which relates the motion of a monotonic propagating front to the resulting image blur captured on a long-exposure shadowgraph. We use a consumer-level camera to photograph the entire collapse phase of cavitation bubbles. We then demonstrate that both the dynamics of a spherically collapsing bubble and those of a bubble collapsing near a rigid boundary can be accurately reconstructed from this single photograph at a virtual frame rate of up to 2 Mfps on a 24.2 Mpx sensor.

Experimental and Numerical Investigation of the Use of Ultrasonic Waves to Assist Laser Welding

“…Preso et al [17] examine the influence of non-condensable gases on the dynamics and luminescence of cavitation bubbles in water, finding minor effects of air saturation on bubble behaviour. Sieber et al [18] present a novel method for constructing high-speed movies of collapsing cavitation bubbles from a single long-exposure image using a consumer-level camera, enhancing the study of bubble dynamics with high temporal and spatial resolution.…”