中文摘要：

以Couette流动为原型,在壁面Pt原子、液相Ar原子和纳米Cu颗粒相互作用的基础上,考虑与温度相关壁面Pt原子的热振动,建立了热壁作用下超薄纳米流体剪切流动的分子动力学模型.研究发现,壁面Pt原子的振动对纳米流体系统中各颗粒运动的影响显著,Ar原子和纳米Cu颗粒沿膜厚方向呈不均匀分布.由于膜厚方向Ar原子的非均匀分布及纳米Cu颗粒的影响,液膜各层的切向速度在膜厚方向上呈非线性变化,且存在明显的边界速度滑移.壁面剪切速度增大,边界速度滑移率增大,系统温度对速度滑移亦有影响.获得了纳米流体的剪切黏度,其随纳米颗粒体积分数的增大而增大.

英文摘要：

A molecular dynamics model of Couette flow was established to investigate the shear flow characteristics of ultra-thin nanofluid film, taking into account the interactions among Cu nanoparticles, Ar atoms and Pt atoms. The temperature-related vibration of Pt atoms in the two parallel solid walls was considered in the model. It is revealed that the vibration of Pt atoms has an obvious influence on the motion of Ar atoms and Cu nanoparticles which distribute unevenly along film thickness direction. Due to the uneven distribution of Ar atoms and the effect of Cu nanoparticles, the tangential velocity of the liquid layers varies nonlinearly along thickness direction. At wall boundary there exists obvious slip velocity influenced by system temperature, and it increases with increasing shearing velocity of the slid walls. The shear viscosity of nanofuild was found to increase with increasing volume fraction of Cu nanoparticles.