On the evaporation rate of ultra-thin liquid film at the nanostructured surface: A molecular dynamics study
On the evaporation rate of ultra-thin liquid film at the nanostructured surface: A molecular dynamics study
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DOI：
10.1016/j.ijthermalsci.2009.06.001
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发表时间：
2010-01-01
影响因子：
4.5
通讯作者：
Tsuruta, Takaharu
中科院分区：
文献类型：
--
作者：
Nagayama, Gyoko;Kawagoe, Masako;Tsuruta, Takaharu
采用分子动力学模拟方法研究了纳米结构对固体表面超薄液膜蒸发速率的影响。在非平衡模拟系统中，简单Lennard-Jones（LJ）流体被模拟为超薄液膜。液体膜被限制在由两个固体表面组成的纳米通道中，所述固体表面设计有分子尺度不均匀形状的纳米结构。用修正的LJ函数表示固液分子间的势函数，对不同表面润湿性的固液界面进行传导。对于稳态非平衡MD模拟，液膜受到通过纳米结构表面的稳态热通量的影响。结果表明，纳米结构表面的界面热阻降低，由于表面积的增加，传热得到明显的增强。对于非稳态非平衡MID模拟，蒸汽被夹在液体膜之间，分别与高温和低温的纳米结构表面接触。结果表明，当膜厚大于吸附层厚度时，超薄液膜的蒸发速率比平坦表面的蒸发速率大。(C)2009年Elsevier Masson SAS。All rights reserved.
Molecular dynamic (MD) simulations have been carried out to study the effect of the nanostructures on the evaporation rate of the ultra-thin liquid film at the solid surface. Simple Lennard-Jones (LJ) fluids are simulated as the ultra-thin liquid film in the non-equilibrium simulation system. The liquid film is confined in a nanochannel composed of two solid surfaces designed with nanostructures in a shape of molecular-scale unevenness. The potential function between solid and liquid molecules is represented by a modified LJ function to conduct the solid-liquid interfaces of different surface wettability. For the steady non-equilibrium MD simulation, the liquid film is subjected to the steady heat flux passing through the nanostructured surfaces. It is found that the interface thermal resistance decreases at the nanostructured surface and apparent heat transfer enhancement is achieved due to the surface area increment. For the unsteady non-equilibrium MID simulation, the vapor has been sandwiched between the liquid films in contact with the nanostructured surfaces of high and low temperature respectively. It is found that the evaporation rate of the ultra-thin liquid film has a larger value than that of the flat surface when the film thickness is larger than that of the adsorbed layer. (C) 2009 Elsevier Masson SAS. All rights reserved.