在石墨烯纳米通道中的分子对齐介导的棒滑式Poiseuille油流
Shiwen Wu1, Zhihao Xu2, Ruda Jian1
1Department of Mechanical Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States.
The journal of physical chemistry. B
|June 27, 2023
概括
纳米通道中的油流可能会出乎意料地表现出粘滑行为,特别是对于像n-dodecane这样的更长的碳化合物链. 这种由分子对齐变化驱动的现象挑战了以前关于石墨烯纳米通道稳定流动的假设.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 纳米通道中的油流对于运输应用至关重要.
- 之前的模拟假定在压力梯度下,油流在压力梯度下稳定.
- 了解纳米尺度的流动力学是必不可少的.
研究的目的:
- 在石墨烯纳米通道中研究不同碳化合物链长度的石油的流动行为.
- 为了探索从稳定流预测的偏差.
- 阐明非稳定流动的基本机制.
主要方法:
- 非平衡分子动力学 (NEMD) 模拟.
- 在石墨烯纳米通道中模拟Poiseuille油流 (三种碳化合物链长度).
- 对分子行为和速度概况的统计分析.
主要成果:
- 观察到n-多德 (最长的碳化合物链) 的非稳定,粘滑流动行为.
- 确定了高速滑动和低速度粘合相之间的交替.
- 在过渡过程中,记录有高达40次的突然速度变化.
- 将粘滑行为与在石墨烯壁附近的分子对齐变化联系在一起.
结论:
- 石墨烯纳米通道中的油流可以表现出复杂的棒滑动力学,与稳定状态假设相反.
- 靠近墙壁的分子对齐是n-dodecane的棒滑行为的主要驱动因素.
- 这些发现为纳米级流体运输和摩擦提供了新的见解,指导了未来的应用.
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