Diffusion of fluid confined to nanotube with rectangular cross section

作者：Devi Reena; Sood Jyoti; Srivastava Sunita; Tankeshwar K^*

来源：Microfluidics and Nanofluidics, 2010, 9(4-5): 737-742.

DOI：10.1007/s10404-010-0587-2

• Nanotube
• Diffusion
• Confinement

A dynamical model is proposed to study self-diffusion coefficient by confining the fluid in rectangular nanotube. The theoretical model is based on the consideration that the confinement affects the movement at atomic level. The model predicts that the diffusion parallel to walls of channel is different from that of diffusion perpendicular to the walls. Near the walls the dynamics of fluid has been found to slow down to an extent that below a certain value of ratio of width to the diameter of particle, the molecules behave as if these belong to solid. The results are contrasted with the result obtained from the model based on similar considerations for a fluid confined only in one direction. It is found that tendency of freezing near the wall increases due to confinement from second direction. Empirical relation which governs the behavior of diffusion coefficient as function of distance from the confining walls has also been proposed. The effect of confinement is more pronounced for denser fluids than for dilute fluid.

• 出版日期2010-10