Interaction of two oscillating bubbles near a rigid boundary

Oscillating bubbles or non-equilibrium bubbles are known to induce the development of liquid jets in the presence of a nearby rigid boundary. The liquid jets can be useful in many applications such as surface cleaning and drug delivery into biological cells. Single bubble oscillation near a rigid boundary has been studied in detail in the literature. In this paper, we extend the research in this area to a two-bubble system near a rigid boundary using high speed photography. Various measurements on the direction of the (bubble-collapse induced) water jets were performed. We identified the parameter sets where the influence of the adjacent bubble and the rigid boundary is important. The experimental results are summarized in a graph that enables easy prediction of the direction of the water jets induced by bubble collapse near another bubble and a rigid boundary.