Cavity collapse near slot geometries
Cavity collapse near slot geometries
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DOI：
10.1017/jfm.2020.552
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发表时间：
2020-04
影响因子：
3.7
通讯作者：
Elijah D. Andrews;D. F. Rivas;I. Peters
中科院分区：
文献类型：
--
作者：
Elijah D. Andrews;D. F. Rivas;I. Peters
当气泡或蒸汽泡在固体边界附近破裂时，会产生一股直接射向边界的射流。这种射流产生的高表面压力和剪切应力可能会损坏或清洁表面。更复杂的几何形状将导致坍塌行为的变化，特别是喷流的方向。以前的大多数研究都集中在简单的平坦边界或复杂性有限的情况下。目前，人们对复杂的几何结构如何影响气泡破裂知之甚少。我们用数值和实验的方法研究了平坦边界上的缝隙对单个气泡的射流方向的影响。我们使用边界元模型来预测射流方向如何依赖于关键的几何参数，并表明当参数适当归一化时，结果将收缩为单条曲线。然后，我们用激光诱导空化的方法对预测进行了实验验证，并将实验结果与预测的相关性进行了比较。这项研究揭示了射流指向远离缝隙的趋势，并表明对于足够高的缝隙，射流方向与缝隙高度无关。
Abstract The collapse of a gas or vapour bubble near a solid boundary produces a jet directed towards the boundary. High surface pressure and shear stress induced by this jet can damage, or clean, the surface. More complex geometries will result in changes in collapse behaviour, in particular the direction of the jet. The majority of prior research has focused on simple flat boundaries or cases with limited complexity. There is currently very little known about how complex geometries affect bubble collapse. We numerically and experimentally investigate how a slot in a flat boundary affects the jet direction for a single bubble. We use a boundary element model to predict how the jet direction depends on key geometric parameters and show that the results collapse to a single curve when the parameters are normalised appropriately. We then experimentally validate the predictions using laser-induced cavitation and compare the experimental results to the predicted dependencies. This research reveals a tendency for the jet to be directed away from a slot and shows that the jet direction is independent of slot height for slots of sufficient height.