洞化和蒸汽泡在水友和疏水表面的形成开始
Chensen Lin1, Martin R Maxey2, Zhen Li3
1Artificial Intelligence Innovation and Incubation Institute, Fudan University, Shanghai 200433, People's Republic of China.
概括
使用多体消散粒子动力学 (mDPD) 弥合分子和宏观化现象的中等尺度模拟. 模拟揭示了墙壁特性如何影响液体中的核形成,泡动力学和压力脉冲.
科学领域:
- 流体动力学 流体动力学
- 材料科学 材料科学 材料科学
- 计算物理 计算物理
背景情况:
- 洞化,即蒸汽泡的形成,通常需要在纯液体中显著的负压.
- 经典核化理论 (CNT) 提供了洞化率估计,但经常显示分子规模预测和宏观观测之间的差异.
- 弥合这些尺度对于理解和预测化行为至关重要.
研究的目的:
- 通过使用中等尺度模拟来研究不同尺度的化现象.
- 探索墙壁特性 (水友性,中性,疏水性) 对化核和动态的影响.
- 分析化过程中产生的压力脉冲和泡相互作用.
主要方法:
- 介面尺度模拟采用多体消散粒子动力学 (mDPD),一种粗的分子动力学 (MD) 方法.
- 在恒温下,在光滑的平面壁之间限制液体层.
- 通过扩大围绕墙壁的区域来缓慢降低压力,从而诱导腔化.
- 不同的墙壁相互作用潜力模拟不同的湿性质 (水友性,中性,疏水性).
主要成果:
- 在液体体中观察到具有水友性壁的均质核,导致强大的压力脉冲和泡崩.
- 具有近中性接触角度的墙壁上的异质核化 (约. 90°),发生在较低的负压下,振荡较弱.
- 随时观察到具有疏水壁或种子颗粒的异质核,其特点是表面泡的显著波动和合并.
结论:
- 中等尺度模拟有效地弥合了分子和宏观尺度的化,为核化机制提供了洞察力.
- 墙壁的湿透性显著影响洞穴形成,泡动态和相关的压力波.
- 这项研究强调了考虑墙壁相互作用对于准确的洞穴建模和预测的重要性.
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