物理化学学报 >> 2009, Vol. 25 >> Issue (05): 994-998.doi: 10.3866/PKU.WHXB20090404

研究论文 上一篇    下一篇

纳米通道内混合气体流动的分子动力学模拟

解辉 刘朝 刘彬武   

  1. 重庆大学动力工程学院, 重庆 400030
  • 收稿日期:2008-11-26 修回日期:2008-12-30 发布日期:2009-05-04

Molecular Dynamics Simulation of Gas Mixture Flow in Nanochannel

XIE Hui, LIU Chao, LIU Bin-Wu   

  1. College of Power Engineering, Chongqing University, Chongqing 400030, P. R. China
  • Received:2008-11-26 Revised:2008-12-30 Published:2009-05-04

摘要:

采用非平衡分子动力学方法, 模拟了混合气体在纳米通道中的Poiseuille流动. 结果显示气体混合物的化学成分与物理结构不再均匀一致, 随着亲水性气体粒子的减少, 亲水性粒子逐渐被吸附于壁面, 而疏水性粒子主要分布于通道中间. 当亲水性粒子为10%时, 混合气体在壁面处形成有序的“类固体”. 在本文的模拟条件下, 流体速度分布显示混合气体流动速度随着疏水性粒子比例的增加而升高; 同时, 混合气体滑移速度也从负滑移速度逐渐转变为正滑移速度.

关键词: 纳米流动, 混合气体, 非平衡分子动力学, 纳米通道, Poiseuille流动

Abstract:

Non-equilibrium molecular dynamic simulations have been carried out to study the Poiseuille flow of a mixture of gases in nanochannels. Results reveal that the chemical composition of these mixtures and their physical structures are not uniform. Hydrophilic particles were gradually absorbed by the channel wall as the proportion of hydrophilic particles decreased while the hydrophobic particles were mainly situated in the middle of the channel. At a proportion of 10% hydrophilic particles the gas mixture is solid-like adjacent to the wall. The distribution of velocity shows that the flow speeds up with an increase in hydrophobic particles and the slip velocity of gas mixtures changes gradually fromnegative to positive.

Key words: Nano-flow, Gas mixture, Nonequilibriummolecular dynamics, Nanochannel, Poiseuille flow

MSC2000: 

  • O645