抄録
Effects of an opposite secondary wall for intensification of the liquid jet that is formed through the near wall bubble collapse were numerically investigated. The axisymmetric form of the Navier-Stokes equations was solved to predict the flow conditions inside and outside the bubble. The volume of fluid approach was incorporated to capture the bubble surface. Putting an opposite secondary wall in the same distance from the bubble center as the primary wall distance, necking of the bubble was observed after the bubble reaches to its maximum volume. After the bubble splitting occurred, formation of two separating jets toward the primary and secondary walls was observed. It was notable that putting the secondary wall leads to the formation of the jet with a higher velocity magnitude. Also the jet velocity magnitude increased with increasing the secondary wall distance from the bubble center up to a certain limit. These analyses were performed for several initial inside to outside pressure ratios of the bubble. The results of the present simulations can be implemented to improve the tasks applying the near wall bubble collapse, like the collapsing bubble induced micro-pump.
