微尺度流道内液体表观黏性系数的分子理论

在考虑分子间作用力的基础上，讨论了各向同性壁面对微流道内非极性分子液体表观黏性系数的影响，建立了考虑壁面影响的表观黏性系数分子理论公式.研究结果显示，在靠近壁面处，壁面对表观黏性系数的影响是很大的，这取决于壁面材料和流体介质的分子间作用力.随着离开壁面距离的增加，壁面对表观黏性系数的影响衰减很快.在液态氩为流体介质的条件下，壁面影响大约可涉及到第10层氩分子，即影响深度为4 nm左右. 关键词： 微尺度流道 表观黏性系数 固壁影响 分子理论

Molecular theory of apparent viscosity of liquid in microchannels

By considering the effect of intermolecular force, the apparent viscosity of non-polar-molecular liquid flowing in microchannels with isotropic solid wall is studied. The molecular theory of apparent viscosity in microchannel taking into account the effects of channel walls is proposed. Numerical results show that the effect of the wall on liquid apparent viscosity can be very strong. The intensity of effect is determined by the intermolecular force between the liquid and the wall. Meanwhile, the effect of the wall decreases rapidly with the increase of distance from the wall. For liquid argon, the extent of influence is within 10 layers of molecules, which is about 4 nm from the wall.