Study on the Collapsing Mechanism of an Oscillating Bubble Above a Porous Rigid Wall
摘要
In this study, a series of experiments on spark-generated bubble oscillating near a porous rigid wall are conducted to investigate the characteristics of non-spherical oscillation and corresponding jet dynamics of the bubble. A high-speed camera is used to record the bubble behavior and several pressure sensors are installed at various positions on the wall surface to measure pressures caused by the collapsing bubble. Additionally, the ALE method is adopted to simulate the complex bubble behaviors and analyze the distribution of the velocity and pressure field. Combining with the numerical and experimental method, effects of typical parameters containing hole radius ( \(\gamma_{R}\) ), distances between the holes ( \(\gamma_{D}\) ), and bubble-wall distance ( \(\gamma_{H}\) ), on the bubble collapse and resultant jet impacting loads are systemically discussed. The result is expected to give an in-depth understanding on the mechanism of the bubble interacting with a porous wall and perhaps also provide reference for the design of porous protective structure under underwater explosion.