Bubble dynamics-from single bubbles to ensembles

In a sound field a bubble is forced to oscillate and behaves like a strongly nonlinear oscillator. Moreover, this oscillator alters its parameters by diffusion of gas into and out of the bubble and opens up new dimensions when starting surface oscillations. Theoretical models that incorporate these phenomena are investigated. Part of the parameter space given by the amplitude and frequency of the sound field and by the bubble radius is scanned to get the regions of stable bubble oscillations with respect to diffusion and surface oscillations. Experimentally, single bubbles can be investigated best either by keeping them in a trap or by generating them by focused laser light. For interaction studies with two bubbles a trapped bubble and a laser bubble have been taken. The motion of the bubbles and their interaction is studied by high speed photography and compared with bubble interaction models.