微流体喷流对深水池的影响:从毛细血管主导的腔封闭过渡到气体压力主导的封闭,在较高的韦伯数下
Thijmen B Kroeze1, David Fernandez Rivas1, Miguel A Quetzeri-Santiago2
1Mesoscale Chemical Systems Group, MESA+ Institute and Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands.
概括
液体喷射冲击会产生空洞,它们以两种不同的方式崩:毛细血管主导的深密封或气体主导的表面密封. 这项研究阐明了用于工程和环境应用的空洞动态.
科学领域:
- 流体动力学 流体动力学
- 多相流的流量是多相的.
- 表面张力现象 表面张力现象
背景情况:
- 液体喷射对液体池的影响对许多工程和环境过程至关重要.
- 洞穴形成和崩动态是喷射撞击期间的关键现象.
- 了解这些动态对于从污染物运输到增材制造的应用至关重要.
研究的目的:
- 在不同的撞击速度和气体密度下,以数值的方式研究空洞崩的动态.
- 根据现有的理论和实验数据验证数值模型.
- 确定控制腔内崩机制的不同制度.
主要方法:
- 在Basilisk C中使用一个轴对称模型进行数值模拟.
- 探索了一系列撞击速度和气体密度的范围.
- 根据韦伯数 (We) 推导了基于韦伯数 (We) 的缩放参数,以分析空洞关闭时间和最大半径.
主要成果:
- 确定了两个不同的腔内崩模式:毛细血管主导的深密封 (We 150) 和气体主导的表面密封 (We 180).
- 证明深海发生在表面以下,而表面海发生在表面以上.
- 观察到最大气体速度的三个关键时刻:撞击前,空洞崩和崩后的滴滴喷射.
结论:
- 腔内崩机制依赖于韦伯数,表明不同的毛细管和气体惯性主导的模式.
- 衍生出的缩放参数提供了对空洞关闭时间和大小的定量见解.
- 这些发现适用于了解水中环境中的污染物分散,以及优化工业流程,如增材制造和无针注射.
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